Factors influencing visual attention switch in multi-display user interfaces: a survey
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paper_title: Distributed user interface elements to support smart interaction spaces

paper_content:

In this paper we show how an interactive system can be distributed among several peer devices. By taking advantage of the current trend towards ambient intelligent environments, we can make use of a combination of computing resources in the surrounding of the user to function as one logical interactive system; an interaction space. Our approach relies on the fact that nowadays most computing resources are network enabled and publish their device profile using some special purpose protocol. For this reason, federations of devices that support the tasks of the user can be composed automatically according to the requirements of these tasks. This distribution of the user interface over a federation of devices can be local or nonlocal. It raises the opportunity for supporting collaborative tasks with the same user interface with little or no extra effort from the user interface designer. Future tools supporting the design, creation and deployment of distributed interactive systems using device federations should maintain usability and usefulness of a dynamic distributed system. We use two different metrics to cope with these problems: interface completeness and interface continuity.
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paper_title: Flexible interface migration

paper_content:

The goal of this work is to provide users immersed in a multi-platform environment with the possibility of interacting with an application while freely moving from one device to another. We describe the solution that we have developed for a service to support platform-aware runtime migration for Web applications. This allows users interacting with an application to change device and continue their interaction from the same point. The service performs the migration of the application taking into account its runtime state and adapting the application interface to the features of the target platforms. The service is optimized for applications developed through a model-based, multiple-level approach. The intelligence of the adaptive interfaces resides in the migration server, which adapts data collected at runtime from their original format to the format best fitting the features of the target platform. We also indicate how it is possible to extend this result in order to support partial migration and synergistic access, by which a part of the user interface is kept on one device during runtime and the remaining part is moved to another with different characteristics.
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paper_title: A Note on the Concept of the Visual Field in Neurology, Psychology, and Visual Neuroscience

paper_content:

Some current confusions in visual neuroscience and psychology over the use of the terms ‘visual field’, ‘field of vision’, ‘stimulus field’, and topographic ‘brain maps’ are reviewed. These are often used as synonyms, whereas they refer to quite different things. A plea is made that visual scientists should use these terms correctly to avoid conceptual and engineering confusion.
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paper_title: The Cost of Display Switching : A Comparison of Mobile , Large Display and Hybrid UI Configurations

paper_content:

Attaching a large external display can help a mobile device user view more content at once. This paper reports on a study investigating how different configurations of input and output across displays affect performance, subjective workload and preferences in map, text and photo search tasks. Experimental results show that a hybrid configuration where visual output is distributed across displays is worst or equivalent to worst in all tasks. A mobile device-controlled large display configuration performs best in the map search task and equal to best in text and photo search tasks (tied with a mobile-only configuration). After conducting a detailed analysis of the performance differences across different UI configurations, we give recommendations for the design of distributed user interfaces.
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paper_title: Deep shot: a framework for migrating tasks across devices using mobile phone cameras

paper_content:

A user task often spans multiple heterogeneous devices, e.g., working on a PC in the office and continuing the work on a laptop or a mobile phone while commuting on a shuttle. However, there is a lack of support for users to easily migrate their tasks across devices. To address this problem, we created Deep Shot, a framework for capturing the user's work state that is needed for a task (e.g., the specific part of a webpage being viewed) and resuming it on a different device. In particular, Deep Shot supports two novel and intuitive interaction techniques, deep shooting and deep posting, for pulling and pushing work states, respectively, using a mobile phone camera. In addition, Deep Shot provides a concise API for developers to leverage its services and make their application states migratable. We demonstrated that Deep Shot can be used to support a range of everyday tasks migrating across devices. An evaluation consisting of a series of experiments showed that our framework and techniques are feasible.
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paper_title: Effects of Visual Separation and Physical Discontinuities when Distributing Information across Multiple Displays

paper_content:

Systems that include multiple integrated displays distributed throughout the working environment are becoming prevalent. Compared to traditional desktop displays, information presented on such systems is typically separated at much wider visual angles. Additionally, since displays are often placed at different depths or are framed by physical bezels, they introduce physical discontinuities in the presentation of information. In this paper, we describe a study that utilizes a divided attention paradigm to explore the effects of visual separation and physical discontinuities when distributing information across multiple displays. Results show reliable, though small, detrimental effects when information is separated within the visual field, but only when coupled with an offset in depth. Surprisingly, physical discontinuities such as monitor bezels and even separation in depth alone do not seem to affect performance on the set of tasks tested. Following the findings, we provide recommendations for the design of hardware and software in multiple display environments.
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paper_title: There and Back Again: Cross-Display Object Movement in Multi-Display Environments

paper_content:

ABSTRACT Multi-display environments (MDEs) are now becoming common, and are becoming more complex, with more displays and more types of display in the environment. One crucial requirement specific to MDEs is that users must be able to move objects from one display to another; this cross-display movement is a frequent and fundamental part of interaction in any application that spans two or more display surfaces. Although many cross-display movement techniques exist, the differences between MDEs—the number, location, and mixed orientation of displays, and the characteristics of the task they are being designed for—require that interaction techniques be chosen carefully to match the constraints of the particular environment. As a way to facilitate interaction design in MDEs, we present a taxonomy that classifies cross-display object movement techniques according to three dimensions: the referential domain that determines how displays are selected, the relationship of the input space to the display configurat...
---
paper_title: Distributed user interface elements to support smart interaction spaces

paper_content:

In this paper we show how an interactive system can be distributed among several peer devices. By taking advantage of the current trend towards ambient intelligent environments, we can make use of a combination of computing resources in the surrounding of the user to function as one logical interactive system; an interaction space. Our approach relies on the fact that nowadays most computing resources are network enabled and publish their device profile using some special purpose protocol. For this reason, federations of devices that support the tasks of the user can be composed automatically according to the requirements of these tasks. This distribution of the user interface over a federation of devices can be local or nonlocal. It raises the opportunity for supporting collaborative tasks with the same user interface with little or no extra effort from the user interface designer. Future tools supporting the design, creation and deployment of distributed interactive systems using device federations should maintain usability and usefulness of a dynamic distributed system. We use two different metrics to cope with these problems: interface completeness and interface continuity.
---
paper_title: A taxonomy for and analysis of multi-person-display ecosystems

paper_content:

Interactive displays are increasingly being distributed in a broad spectrum of everyday life environments: they have very diverse form factors and portability characteristics, support a variety of interaction techniques, and can be used by a variable number of people. The coupling of multiple displays creates an interactive "ecosystem of displays". Such an ecosystem is suitable for particular social contexts, which in turn generates novel settings for communication and performance and challenges in ownership. This paper aims at providing a design space that can inform the designers of such ecosystems. To this end, we provide a taxonomy that builds on the size of the ecosystem and on the degree of individual engagement as dimensions. We recognize areas where physical constraints imply certain kinds of social engagement, versus other areas where further work on interaction techniques for coupling displays can open new design spaces.
---
paper_title: Connectables: dynamic coupling of displays for the flexible creation of shared workspaces

paper_content:

We present the ConnecTable, a new mobile, networked and context-aware information appliance that provides affordances for pen-based individual and cooperative work as well as for the seamless transition between the two. In order to dynamically enlarge an interaction area for the purpose of shared use, a flexible coupling of displays has been realized that overcomes the restrictions of display sizes and borders. Two ConnecTable displays dynamically form a homogeneous display area when moved close to each other. The appropriate triggering signal comes from built-in sensors allowing users to temporally combine their individual displays to a larger shared one by a simple physical movement in space. Connected ConnecTables allow their users to work in parallel on an ad-hoc created shared workspace as well as exchanging information by simply shuffling objects from one display to the other. We discuss the user interface and related issues as well as the software architecture. We also present the physical realization of the ConnecTables.
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paper_title: SyncTap: synchronous user operation for spontaneous network connection

paper_content:

This paper introduces the concept of synchronous user operation, a user interface technique for establishing spontaneous network connections between digital devices. This concept has been implemented in the “SyncTap system”, which allows a user to establish device connections through synchronous button operations. When the user wants to connect two devices, she synchronously presses and releases the “connection” buttons on both devices. Then, multicast packets containing button press and release timing information are sent through the network. By comparing this timing information with locally recorded information, the devices can correctly identify each other. This scheme is simple but scalable because it can detect and handle simultaneous overlapping connection requests. It can also be used to establish secure connections by exchanging public keys. This paper describes the principle, the protocol, and various applications in the domain of ubiquitous computing.
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paper_title: Ubiquitous graphics: combining hand-held and wall-size displays to interact with large images

paper_content:

Ubiquitous Graphics addresses the problem of interacting with very large computer graphics images, for instance an online map or a large digitized painting. It uses a combination of mobile and stationary displays to show both overview and detail. The main image is displayed using a projector or other large traditional display. To access details, the user holds a mobile device in front of the stationary display. Using ultrasonic tracking the smaller display is aligned with the overview, giving access to a corresponding portion of the image in higher resolution. Alternatively the system provides "magic lens" functionality that can show additional information. Users may add free-form annotations and pre-defined graphical objects by interacting directly with the mobile device. In a user study, subjects drew better descriptive maps using the system than an ordinary map application. The system is robust and was demonstrated to several thousand people in a week-long public exhibit.
---
paper_title: E-conic: a perspective-aware interface for multi-display environments

paper_content:

Multi-display environments compose displays that can be at different locations from and different angles to the user; as a result, it can become very difficult to manage windows, read text, and manipulate objects. We investigate the idea of perspective as a way to solve these problems in multi-display environments. We first identify basic display and control factors that are affected by perspective, such as visibility, fracture, and sharing. We then present the design and implementation of E-conic, a multi-display multi-user environment that uses location data about displays and users to dynamically correct perspective. We carried out a controlled experiment to test the benefits of perspective correction in basic interaction tasks like targeting, steering, aligning, pattern-matching and reading. Our results show that perspective correction significantly and substantially improves user performance in all these tasks.
---
paper_title: PDAs and shared public displays: Making personal information public, and public information personal

paper_content:

We are investigating how people move from individual to group work through the use of both personal digital assistants (PDAs) and a shared public display. Our scenario of this work covers the following activities. First, mobile individuals can create “personal” notes on their PDAs. Second, when individuals meet in real time, they can selectively “publicise” notes by moving them to a shared public display. Third, the group can manipulate personal and public items in real time through both PDAs and the shared public display, where the notes contained on both PDAs and public display are automatically synchronised. Finally, people leave a meeting with a common record of their activity. We describe our SharedNotes system that illustrates how people move through this scenario. We also highlight a variety of problematic design issues that result from having different devices and from having the system enforce a rigid distinction between personal and public information.
---
paper_title: UbiTable: Impromptu Face-to-Face Collaboration on Horizontal Interactive Surfaces

paper_content:

Despite the mobility enabled by the plethora of technological tools such as laptops, PDA and cell phones, horizontal flat surfaces are still extensively used and much preferred for on-the-move face-to-face collaboration. Unfortunately, when digital documents need to be shared during collaboration, people are still mostly constrained to display surfaces that have been designed for single users, such as laptops and PDAs. Technologically there is a lack of computational support for shared digital document access, browsing, visualization and manipulation on horizontal surfaces. We believe support for such serendipitous meetings will play a critical role in future ubiquitous computing spaces. Our UbiTable project examines the design space of tabletops used as scrap displays. Scrap displays support kiosk-style walk-up interaction for impromptu face-to-face collaboration. Our design offers the affordances of a physical table. It provides the flexibility by allowing users to layout shared documents with desired orientation and position; at the same time it augments traditional paper-based interactions by providing a flexible gradient or shades of sharing semantics. UbiTable addresses visual accessibility vs. electronic accessibility of documents, an issue which is critical to ubiquitous environments.
---
paper_title: A taxonomy for and analysis of multi-person-display ecosystems

paper_content:

Interactive displays are increasingly being distributed in a broad spectrum of everyday life environments: they have very diverse form factors and portability characteristics, support a variety of interaction techniques, and can be used by a variable number of people. The coupling of multiple displays creates an interactive "ecosystem of displays". Such an ecosystem is suitable for particular social contexts, which in turn generates novel settings for communication and performance and challenges in ownership. This paper aims at providing a design space that can inform the designers of such ecosystems. To this end, we provide a taxonomy that builds on the size of the ecosystem and on the degree of individual engagement as dimensions. We recognize areas where physical constraints imply certain kinds of social engagement, versus other areas where further work on interaction techniques for coupling displays can open new design spaces.
---
paper_title: Ubiquitous Cursor: A Comparison of Direct and Indirect Pointing Feedback in Multi-Display Environments

paper_content:

Multi-display environments (MDEs) connect several displays into a single digital workspace. One of the main problems to be solved in an MDE's design is how to enable movement of objects from one display to another. When the real-world space between displays is modeled as part of the workspace (i.e., Mouse Ether), it becomes difficult for users to keep track of their cursors during a transition between displays. To address this problem, we developed the Ubiquitous Cursor system, which uses a projector and a hemispherical mirror to completely cover the interior of a room with usable low-resolution pixels. Ubiquitous Cursor allows us to provide direct feedback about the location of the cursor between displays. To assess the effectiveness of this direct-feedback approach, we carried out a study that compared Ubiquitous Cursor with two other standard approaches: Halos, which provide indirect feedback about the cursor's location; and Stitching, which warps the cursor between displays, similar to the way that current operating systems address multiple monitors. Our study tested simple cross-display pointing tasks in an MDE; the results showed that Ubiquitous Cursor was significantly faster than both other approaches. Our work shows the feasibility and the value of providing direct feedback for cross-display movement, and adds to our understanding of the principles underlying targeting performance in MDEs.
---
paper_title: Partitioning digital worlds: focal and peripheral awareness in multiple monitor use

paper_content:

Software today does not help us partition our digital worlds effectively. We must organize them ourselves. This field study of users of multiple monitors examines how people with a lot of display space arrange information. Second monitors are generally used for secondary activities related to principal tasks, for peripheral awareness of information that is not the main focus, and for easy access to resources. A second monitor improves efficiency in ways that are difficult to measure yet can have substantial subjective benefit. The study concludes with illustrations of shortcomings of today's systems and applications: the way we work could be improved at relatively low cost.
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paper_title: Comparing content and input redirection in MDEs

paper_content:

Designers of Multi-Display Environments (MDEs) often use input redirection to allow users to manipulate content on multiple displays with a single interaction device, but users seated at sub-optimal positions (i.e., not facing the display) may find interaction difficult or frustrating. In collaborative MDEs, users should be able to choose their preferred collaborative arrangement, rather than adjusting to the limitations of the technology. We compare content and input redirection from a variety of seating positions in an MDE. Results from our studies show that content redirection does not suffer from performance loss in sub-optimal seating positions, as opposed to input redirection, which does. Content redirection provides a method for all members of a group to interact with shared content regardless of their position relative to a shared display.
---
paper_title: An interactive Landscape for Creativity and Innovation

paper_content:

We describe the i-LAND environment which constitutes an example of our vision of the workspaces of the future, in this case supporting cooperative work of dynamic teams with changing needs. i-LAND requires and provides new forms of human-computer interaction and new forms of computer-supported cooperative work. Its design is based on an integration of information and architectural spaces, implications of new work practices and an empirical requirements study informing our design. i-LAND consists of several ‘roomware’ components, i.e. computer-augmented objects integrating room elements with information technology. We present the current realization of i-LAND in terms of an interactive electronic wall, an interactive table, two computer-enhanced chairs, and two “bridges” for the Passage-mechanism. This is complemented by the description of the creativity support application and the technological infrastructure. The paper is accompanied by a video figure in the CHI’99 video program.
---
paper_title: Guidelines for using multiple views in information visualization

paper_content:

A multiple view system uses two or more distinct views to support the investigation of a single conceptual entity. Many such systems exist, ranging from computer-aided design (CAD) systems for chip design that display both the logical structure and the actual geometry of the integrated circuit to overview-plus-detail systems that show both an overview for context and a zoomed-in-view for detail. Designers of these systems must make a variety of design decisions, ranging from determining layout to constructing sophisticated coordination mechanisms. Surprisingly, little work has been done to characterize these systems or to express guidelines for their design. Based on a workshop discussion of multiple views, and based on our own design and implementation experience with these systems, we present eight guidelines for the design of multiple view systems.
---
paper_title: Exploring the effects of group size and display configuration on visual search

paper_content:

Visual search is the subject of countless psychology studies in which people search for target items within a scene. The bulk of this literature focuses on the individual with the goal of understanding the human perceptual system. In life, visual search is performed not only by individuals, but also by groups -- a team of doctors may study an x-ray and a team of analysts may study a satellite photograph. In this paper, we examine the issues one should consider when searching as a group. We present the details of an experiment designed to investigate the impact of group size on visual search performance, and how different display configurations affected that performance. We asked individuals, pairs, and groups of four people to participate in a baggage screening task in which these teams searched simulated x-rays for prohibited items. Teams conducted these searches on single monitors, a row of four monitors, and on a single horizontal display. Our findings suggest that groups commit far fewer errors in visual search tasks, although they may perform slower than individuals under certain conditions. The interaction between group size and display configuration turned out to be an important factor as well.
---
paper_title: The effects of interaction technique on coordination in tabletop groupware

paper_content:

The interaction techniques that are used in tabletop groupware systems (such as pick-and-drop or pantograph) can affect the way that people collaborate. However, little is known about these effects, making it difficult for designers to choose appropriate techniques when building tabletop groupware. We carried out an exploratory study to determine how several different types of interaction techniques (pantograph, telepointers, radar views, drag-and-drop, and laser beam) affected coordination and awareness in two tabletop tasks (a game and a storyboarding activity). We found that the choice of interaction technique significantly affected coordination measures, performance measures, and preference - but that the effects were different for the two different tasks. Our study shows that the choice of tabletop interaction technique does indeed matter, and provides insight into how tabletop systems can better support group work.
---
paper_title: LensMouse: augmenting the mouse with an interactive touch display

paper_content:

We introduce LensMouse, a novel device that embeds a touch-screen display -- or tangible 'lens' -- onto a mouse. Users interact with the display of the mouse using direct touch, whilst also performing regular cursor-based mouse interactions. We demonstrate some of the unique capabili-ties of such a device, in particular for interacting with auxil-iary windows, such as toolbars, palettes, pop-ups and dia-log-boxes. By migrating these windows onto LensMouse, challenges such as screen real-estate use and window man-agement can be alleviated. In a controlled experiment, we evaluate the effectiveness of LensMouse in reducing cursor movements for interacting with auxiliary windows. We also consider the concerns involving the view separation that results from introducing such a display-based device. Our results reveal that overall users are more effective with LenseMouse than with auxiliary application windows that are managed either in single or dual-monitor setups. We conclude by presenting other application scenarios that LensMouse could support.
---
paper_title: Dynamo: a public interactive surface supporting the cooperative sharing and exchange of media

paper_content:

In this paper we propose a novel way of supporting occasional meetings that take place in unfamiliar public places, which promotes lightweight, visible and fluid collaboration. Our central idea is that the sharing and exchange of information occurs across public surfaces that users can easily access and interact with. To this end, we designed and implemented Dynamo, a communal multi-user interactive surface. The surface supports the cooperative sharing and exchange of a wide range of media that can be brought to the surface by users that are remote from their familiar organizational settings.
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paper_title: Siftables: towards sensor network user interfaces

paper_content:

This paper outlines Siftables, a novel platform that applies technology and methodology from wireless sensor networks to tangible user interfaces in order to yield new possibilities for human-computer interaction. Siftables are compact devices with sensing, graphical display, and wireless communication. They can be physically manipulated as a group to interact with digital information and media. We discuss the unique affordances that a sensor network user interface (SNUI) such as Siftables provides, as well as the resulting directness between the physical interface and the data being manipulated. We conclude with a description of some gestural language primitives that we are currently prototyping with Siftables.
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paper_title: Targeting across displayless space

paper_content:

Multi-monitor displays and multi-display environments are now common. Cross-display cursor movement, in which a user moves the pointer from one display to another, occurs frequently in these settings. There are several techniques for supporting this kind of movement, and these differ in the way that they deal with displayless space (the physical space between displays). Stitching is the method used by most operating systems; in this technique, the cursor jumps from the edge of one display directly into the next display. In contrast, Mouse Ether maps the motor space of the mouse exactly to the physical space of the displays, meaning that the cursor has to travel across displayless space until it reaches the next display. To determine which of these approaches is best for cross-display movement, we carried out a study comparing Stitching, Mouse Ether, and a variant of Mouse Ether with Halo for off-screen feedback. We found that Stitching is equivalent to or faster than any variant of Mouse Ether, and that Halo improves Ether's performance (but not enough to outperform Stitching). Results also indicate that the larger the gap between displays, the longer the targeting takes --- even for Stitching. These findings provide valuable guidance for practitioners and raise new interesting questions for research.
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paper_title: Using direct and indirect input devices: Attention demands and age-related differences

paper_content:

Researchers have suggested that attention is a key moderating variable predicting performance with an input device [Greenstein and Arnaut 1988], although the attention demands of devices have not been directly investigated. We hypothesized that the attentional demands of input devices are intricately linked to whether the device matches the input requirements of the on-screen task. Further, matching task and device should be more important for attentionally reduced groups, such as older adults. Younger and older adults used either a direct (touch screen) or indirect (rotary encoder) input device to perform matched or mismatched input tasks under a spectrum of attention allocation conditions. Input devices required attention—more so for older adults, especially in a mismatch situation. In addition, task performance was influenced by the match between task demands and input device characteristics. Though both groups benefited from a match between input device and task input requirements, older adults benefited more, and this benefit increased as less attention was available. We offer an a priori method to choose an input device for a task by considering the overlap between device attributes and input requirements. This data should affect design decisions concerning input device selection across age groups and task contexts.
---
paper_title: The Cost of Display Switching : A Comparison of Mobile , Large Display and Hybrid UI Configurations

paper_content:

Attaching a large external display can help a mobile device user view more content at once. This paper reports on a study investigating how different configurations of input and output across displays affect performance, subjective workload and preferences in map, text and photo search tasks. Experimental results show that a hybrid configuration where visual output is distributed across displays is worst or equivalent to worst in all tasks. A mobile device-controlled large display configuration performs best in the map search task and equal to best in text and photo search tasks (tied with a mobile-only configuration). After conducting a detailed analysis of the performance differences across different UI configurations, we give recommendations for the design of distributed user interfaces.
---
paper_title: Direct-touch vs. mouse input for tabletop displays

paper_content:

We investigate the differences -- in terms of bothquantitative performance and subjective preference -- between direct-touch and mouse input for unimanual andbimanual tasks on tabletop displays. The results of twoexperiments show that for bimanual tasks performed ontabletops, users benefit from direct-touch input. However,our results also indicate that mouse input may be moreappropriate for a single user working on tabletop tasksrequiring only single-point interaction.
---
paper_title: E-conic: a perspective-aware interface for multi-display environments

paper_content:

Multi-display environments compose displays that can be at different locations from and different angles to the user; as a result, it can become very difficult to manage windows, read text, and manipulate objects. We investigate the idea of perspective as a way to solve these problems in multi-display environments. We first identify basic display and control factors that are affected by perspective, such as visibility, fracture, and sharing. We then present the design and implementation of E-conic, a multi-display multi-user environment that uses location data about displays and users to dynamically correct perspective. We carried out a controlled experiment to test the benefits of perspective correction in basic interaction tasks like targeting, steering, aligning, pattern-matching and reading. Our results show that perspective correction significantly and substantially improves user performance in all these tasks.
---
paper_title: Effects of display position and control space orientation on user preference and performance

paper_content:

In many environments, it is often the case that input is made to displays that are positioned non-traditionally relative to one or more users. This typically requires users to perform interaction tasks under transformed input-display spatial mappings, and the literature is unclear as to how such transformations affect performance. We present two experiments that explore the impact of display space position and input control space orientation on user's subjective preference and objective performance in a docking task. Our results provide guidelines as to optimal display placement and control orientation in collaborative computing environments with one or more shared displays.
---
paper_title: Effects of Visual Separation and Physical Discontinuities when Distributing Information across Multiple Displays

paper_content:

Systems that include multiple integrated displays distributed throughout the working environment are becoming prevalent. Compared to traditional desktop displays, information presented on such systems is typically separated at much wider visual angles. Additionally, since displays are often placed at different depths or are framed by physical bezels, they introduce physical discontinuities in the presentation of information. In this paper, we describe a study that utilizes a divided attention paradigm to explore the effects of visual separation and physical discontinuities when distributing information across multiple displays. Results show reliable, though small, detrimental effects when information is separated within the visual field, but only when coupled with an offset in depth. Surprisingly, physical discontinuities such as monitor bezels and even separation in depth alone do not seem to affect performance on the set of tasks tested. Following the findings, we provide recommendations for the design of hardware and software in multiple display environments.
---
paper_title: Effects of interior bezels of tiled-monitor large displays on visual search, tunnel steering, and target selection

paper_content:

Tiled-monitor large displays are widely used in various application domains. However, how their interior bezels affect user performance and behavior has not been fully understood. We conducted three controlled experiments to investigate effects of tiled-monitor interior bezels on visual search, straight-tunnel steering, and target selection tasks. The conclusions of our paper are: 1) interior bezels do not affect visual search time nor error rate; however, splitting objects across bezels is detrimental to search accuracy, 2) interior bezels are detrimental to straight-tunnel steering, but not to target selection. In addition, we discuss how inte-rior bezels affect user behaviors, and suggest guidelines for effectively using tiled-monitor large displays and designing user interfaces suited to them.
---
paper_title: A taxonomy for and analysis of multi-person-display ecosystems

paper_content:

Interactive displays are increasingly being distributed in a broad spectrum of everyday life environments: they have very diverse form factors and portability characteristics, support a variety of interaction techniques, and can be used by a variable number of people. The coupling of multiple displays creates an interactive "ecosystem of displays". Such an ecosystem is suitable for particular social contexts, which in turn generates novel settings for communication and performance and challenges in ownership. This paper aims at providing a design space that can inform the designers of such ecosystems. To this end, we provide a taxonomy that builds on the size of the ecosystem and on the degree of individual engagement as dimensions. We recognize areas where physical constraints imply certain kinds of social engagement, versus other areas where further work on interaction techniques for coupling displays can open new design spaces.
---
paper_title: Ubiquitous Cursor: A Comparison of Direct and Indirect Pointing Feedback in Multi-Display Environments

paper_content:

Multi-display environments (MDEs) connect several displays into a single digital workspace. One of the main problems to be solved in an MDE's design is how to enable movement of objects from one display to another. When the real-world space between displays is modeled as part of the workspace (i.e., Mouse Ether), it becomes difficult for users to keep track of their cursors during a transition between displays. To address this problem, we developed the Ubiquitous Cursor system, which uses a projector and a hemispherical mirror to completely cover the interior of a room with usable low-resolution pixels. Ubiquitous Cursor allows us to provide direct feedback about the location of the cursor between displays. To assess the effectiveness of this direct-feedback approach, we carried out a study that compared Ubiquitous Cursor with two other standard approaches: Halos, which provide indirect feedback about the cursor's location; and Stitching, which warps the cursor between displays, similar to the way that current operating systems address multiple monitors. Our study tested simple cross-display pointing tasks in an MDE; the results showed that Ubiquitous Cursor was significantly faster than both other approaches. Our work shows the feasibility and the value of providing direct feedback for cross-display movement, and adds to our understanding of the principles underlying targeting performance in MDEs.
---
paper_title: An interactive Landscape for Creativity and Innovation

paper_content:

We describe the i-LAND environment which constitutes an example of our vision of the workspaces of the future, in this case supporting cooperative work of dynamic teams with changing needs. i-LAND requires and provides new forms of human-computer interaction and new forms of computer-supported cooperative work. Its design is based on an integration of information and architectural spaces, implications of new work practices and an empirical requirements study informing our design. i-LAND consists of several ‘roomware’ components, i.e. computer-augmented objects integrating room elements with information technology. We present the current realization of i-LAND in terms of an interactive electronic wall, an interactive table, two computer-enhanced chairs, and two “bridges” for the Passage-mechanism. This is complemented by the description of the creativity support application and the technological infrastructure. The paper is accompanied by a video figure in the CHI’99 video program.
---
paper_title: E-conic: a perspective-aware interface for multi-display environments

paper_content:

Multi-display environments compose displays that can be at different locations from and different angles to the user; as a result, it can become very difficult to manage windows, read text, and manipulate objects. We investigate the idea of perspective as a way to solve these problems in multi-display environments. We first identify basic display and control factors that are affected by perspective, such as visibility, fracture, and sharing. We then present the design and implementation of E-conic, a multi-display multi-user environment that uses location data about displays and users to dynamically correct perspective. We carried out a controlled experiment to test the benefits of perspective correction in basic interaction tasks like targeting, steering, aligning, pattern-matching and reading. Our results show that perspective correction significantly and substantially improves user performance in all these tasks.
---
paper_title: UbiTable: Impromptu Face-to-Face Collaboration on Horizontal Interactive Surfaces

paper_content:

Despite the mobility enabled by the plethora of technological tools such as laptops, PDA and cell phones, horizontal flat surfaces are still extensively used and much preferred for on-the-move face-to-face collaboration. Unfortunately, when digital documents need to be shared during collaboration, people are still mostly constrained to display surfaces that have been designed for single users, such as laptops and PDAs. Technologically there is a lack of computational support for shared digital document access, browsing, visualization and manipulation on horizontal surfaces. We believe support for such serendipitous meetings will play a critical role in future ubiquitous computing spaces. Our UbiTable project examines the design space of tabletops used as scrap displays. Scrap displays support kiosk-style walk-up interaction for impromptu face-to-face collaboration. Our design offers the affordances of a physical table. It provides the flexibility by allowing users to layout shared documents with desired orientation and position; at the same time it augments traditional paper-based interactions by providing a flexible gradient or shades of sharing semantics. UbiTable addresses visual accessibility vs. electronic accessibility of documents, an issue which is critical to ubiquitous environments.
---
paper_title: Dynamo: a public interactive surface supporting the cooperative sharing and exchange of media

paper_content:

In this paper we propose a novel way of supporting occasional meetings that take place in unfamiliar public places, which promotes lightweight, visible and fluid collaboration. Our central idea is that the sharing and exchange of information occurs across public surfaces that users can easily access and interact with. To this end, we designed and implemented Dynamo, a communal multi-user interactive surface. The surface supports the cooperative sharing and exchange of a wide range of media that can be brought to the surface by users that are remote from their familiar organizational settings.
---
paper_title: Siftables: towards sensor network user interfaces

paper_content:

This paper outlines Siftables, a novel platform that applies technology and methodology from wireless sensor networks to tangible user interfaces in order to yield new possibilities for human-computer interaction. Siftables are compact devices with sensing, graphical display, and wireless communication. They can be physically manipulated as a group to interact with digital information and media. We discuss the unique affordances that a sensor network user interface (SNUI) such as Siftables provides, as well as the resulting directness between the physical interface and the data being manipulated. We conclude with a description of some gestural language primitives that we are currently prototyping with Siftables.
---
paper_title: Guidelines for using multiple views in information visualization

paper_content:

A multiple view system uses two or more distinct views to support the investigation of a single conceptual entity. Many such systems exist, ranging from computer-aided design (CAD) systems for chip design that display both the logical structure and the actual geometry of the integrated circuit to overview-plus-detail systems that show both an overview for context and a zoomed-in-view for detail. Designers of these systems must make a variety of design decisions, ranging from determining layout to constructing sophisticated coordination mechanisms. Surprisingly, little work has been done to characterize these systems or to express guidelines for their design. Based on a workshop discussion of multiple views, and based on our own design and implementation experience with these systems, we present eight guidelines for the design of multiple view systems.
---
paper_title: Multi-display Composition: Supporting Display Sharing for Collocated Mobile Devices

paper_content:

Multi-display composition is a technique that enables several mobile devices to join together over a wireless network to form a larger logical display. This logical display can be created in an ad hoc manner for use when and where it is needed out of a group of users' existing mobile computers. In this work we present a multi-display composition system and discuss our implementation that supports dynamically extending the display across several devices. Furthermore, we present findings from a study of collocated groups of individuals using multi-display composition on two different types of mobile computers. We found mixed results with respect to the effect of the resulting display area. The use of two devices by a pair of participants tended to be rated more favorably than a corresponding group of four devices and participants. Furthermore, while providing additional screen real estate for smaller UMPCs, tablets were rated more favorably when using our system. Finally, we discuss usage themes that emerged from participants' use of the multi-display composition system.
---
paper_title: UbiTable: Impromptu Face-to-Face Collaboration on Horizontal Interactive Surfaces

paper_content:

Despite the mobility enabled by the plethora of technological tools such as laptops, PDA and cell phones, horizontal flat surfaces are still extensively used and much preferred for on-the-move face-to-face collaboration. Unfortunately, when digital documents need to be shared during collaboration, people are still mostly constrained to display surfaces that have been designed for single users, such as laptops and PDAs. Technologically there is a lack of computational support for shared digital document access, browsing, visualization and manipulation on horizontal surfaces. We believe support for such serendipitous meetings will play a critical role in future ubiquitous computing spaces. Our UbiTable project examines the design space of tabletops used as scrap displays. Scrap displays support kiosk-style walk-up interaction for impromptu face-to-face collaboration. Our design offers the affordances of a physical table. It provides the flexibility by allowing users to layout shared documents with desired orientation and position; at the same time it augments traditional paper-based interactions by providing a flexible gradient or shades of sharing semantics. UbiTable addresses visual accessibility vs. electronic accessibility of documents, an issue which is critical to ubiquitous environments.
---
paper_title: Touch projector: mobile interaction through video

paper_content:

In 1992, Tani et al. proposed remotely operating machines in a factory by manipulating a live video image on a computer screen. In this paper we revisit this metaphor and investigate its suitability for mobile use. We present Touch Projector, a system that enables users to interact with remote screens through a live video image on their mobile device. The handheld device tracks itself with respect to the surrounding displays. Touch on the video image is "projected" onto the target display in view, as if it had occurred there. This literal adaptation of Tani's idea, however, fails because handheld video does not offer enough stability and control to enable precise manipulation. We address this with a series of improvements, including zooming and freezing the video image. In a user study, participants selected targets and dragged targets between displays using the literal and three improved versions. We found that participants achieved highest performance with automatic zooming and temporary image freezing.
---
paper_title: Impact of Item Density on Magic Lens Interactions

paper_content:

We conducted a user study to investigate the effect of visual context in handheld augmented reality interfaces. A dynamic peephole interface (without visual context beyond the device display) was compared to a magic lens interface (with video see-through augmentation of external visual context). The task was to explore objects on a map and look for a specific attribute shown on the display. We tested different sizes of visual context as well as different numbers of items per area, i.e. different item densities. We found that visual context is most effective for sparse item distributions and the performance benefit decreases with increasing density. User performance in the magic lens case approaches the performance of the dynamic peephole case the more densely spaced the items are. In all conditions, subjective feedback indicates that participants generally prefer visual context over the lack thereof. The insights gained from this study are relevant for designers of mobile AR and dynamic peephole interfaces by suggesting when external visual context is most beneficial.
---
paper_title: Flexible interface migration

paper_content:

The goal of this work is to provide users immersed in a multi-platform environment with the possibility of interacting with an application while freely moving from one device to another. We describe the solution that we have developed for a service to support platform-aware runtime migration for Web applications. This allows users interacting with an application to change device and continue their interaction from the same point. The service performs the migration of the application taking into account its runtime state and adapting the application interface to the features of the target platforms. The service is optimized for applications developed through a model-based, multiple-level approach. The intelligence of the adaptive interfaces resides in the migration server, which adapts data collected at runtime from their original format to the format best fitting the features of the target platform. We also indicate how it is possible to extend this result in order to support partial migration and synergistic access, by which a part of the user interface is kept on one device during runtime and the remaining part is moved to another with different characteristics.
---
paper_title: PDAs and shared public displays: Making personal information public, and public information personal

paper_content:

We are investigating how people move from individual to group work through the use of both personal digital assistants (PDAs) and a shared public display. Our scenario of this work covers the following activities. First, mobile individuals can create “personal” notes on their PDAs. Second, when individuals meet in real time, they can selectively “publicise” notes by moving them to a shared public display. Third, the group can manipulate personal and public items in real time through both PDAs and the shared public display, where the notes contained on both PDAs and public display are automatically synchronised. Finally, people leave a meeting with a common record of their activity. We describe our SharedNotes system that illustrates how people move through this scenario. We also highlight a variety of problematic design issues that result from having different devices and from having the system enforce a rigid distinction between personal and public information.
---
paper_title: Ubiquitous graphics: combining hand-held and wall-size displays to interact with large images

paper_content:

Ubiquitous Graphics addresses the problem of interacting with very large computer graphics images, for instance an online map or a large digitized painting. It uses a combination of mobile and stationary displays to show both overview and detail. The main image is displayed using a projector or other large traditional display. To access details, the user holds a mobile device in front of the stationary display. Using ultrasonic tracking the smaller display is aligned with the overview, giving access to a corresponding portion of the image in higher resolution. Alternatively the system provides "magic lens" functionality that can show additional information. Users may add free-form annotations and pre-defined graphical objects by interacting directly with the mobile device. In a user study, subjects drew better descriptive maps using the system than an ordinary map application. The system is robust and was demonstrated to several thousand people in a week-long public exhibit.
---
paper_title: The Cost of Display Switching : A Comparison of Mobile , Large Display and Hybrid UI Configurations

paper_content:

Attaching a large external display can help a mobile device user view more content at once. This paper reports on a study investigating how different configurations of input and output across displays affect performance, subjective workload and preferences in map, text and photo search tasks. Experimental results show that a hybrid configuration where visual output is distributed across displays is worst or equivalent to worst in all tasks. A mobile device-controlled large display configuration performs best in the map search task and equal to best in text and photo search tasks (tied with a mobile-only configuration). After conducting a detailed analysis of the performance differences across different UI configurations, we give recommendations for the design of distributed user interfaces.
---
paper_title: UbiTable: Impromptu Face-to-Face Collaboration on Horizontal Interactive Surfaces

paper_content:

Despite the mobility enabled by the plethora of technological tools such as laptops, PDA and cell phones, horizontal flat surfaces are still extensively used and much preferred for on-the-move face-to-face collaboration. Unfortunately, when digital documents need to be shared during collaboration, people are still mostly constrained to display surfaces that have been designed for single users, such as laptops and PDAs. Technologically there is a lack of computational support for shared digital document access, browsing, visualization and manipulation on horizontal surfaces. We believe support for such serendipitous meetings will play a critical role in future ubiquitous computing spaces. Our UbiTable project examines the design space of tabletops used as scrap displays. Scrap displays support kiosk-style walk-up interaction for impromptu face-to-face collaboration. Our design offers the affordances of a physical table. It provides the flexibility by allowing users to layout shared documents with desired orientation and position; at the same time it augments traditional paper-based interactions by providing a flexible gradient or shades of sharing semantics. UbiTable addresses visual accessibility vs. electronic accessibility of documents, an issue which is critical to ubiquitous environments.
---
paper_title: Ubiquitous Cursor: A Comparison of Direct and Indirect Pointing Feedback in Multi-Display Environments

paper_content:

Multi-display environments (MDEs) connect several displays into a single digital workspace. One of the main problems to be solved in an MDE's design is how to enable movement of objects from one display to another. When the real-world space between displays is modeled as part of the workspace (i.e., Mouse Ether), it becomes difficult for users to keep track of their cursors during a transition between displays. To address this problem, we developed the Ubiquitous Cursor system, which uses a projector and a hemispherical mirror to completely cover the interior of a room with usable low-resolution pixels. Ubiquitous Cursor allows us to provide direct feedback about the location of the cursor between displays. To assess the effectiveness of this direct-feedback approach, we carried out a study that compared Ubiquitous Cursor with two other standard approaches: Halos, which provide indirect feedback about the cursor's location; and Stitching, which warps the cursor between displays, similar to the way that current operating systems address multiple monitors. Our study tested simple cross-display pointing tasks in an MDE; the results showed that Ubiquitous Cursor was significantly faster than both other approaches. Our work shows the feasibility and the value of providing direct feedback for cross-display movement, and adds to our understanding of the principles underlying targeting performance in MDEs.
---
paper_title: Touch projector: mobile interaction through video

paper_content:

In 1992, Tani et al. proposed remotely operating machines in a factory by manipulating a live video image on a computer screen. In this paper we revisit this metaphor and investigate its suitability for mobile use. We present Touch Projector, a system that enables users to interact with remote screens through a live video image on their mobile device. The handheld device tracks itself with respect to the surrounding displays. Touch on the video image is "projected" onto the target display in view, as if it had occurred there. This literal adaptation of Tani's idea, however, fails because handheld video does not offer enough stability and control to enable precise manipulation. We address this with a series of improvements, including zooming and freezing the video image. In a user study, participants selected targets and dragged targets between displays using the literal and three improved versions. We found that participants achieved highest performance with automatic zooming and temporary image freezing.
---
paper_title: LensMouse: augmenting the mouse with an interactive touch display

paper_content:

We introduce LensMouse, a novel device that embeds a touch-screen display -- or tangible 'lens' -- onto a mouse. Users interact with the display of the mouse using direct touch, whilst also performing regular cursor-based mouse interactions. We demonstrate some of the unique capabili-ties of such a device, in particular for interacting with auxil-iary windows, such as toolbars, palettes, pop-ups and dia-log-boxes. By migrating these windows onto LensMouse, challenges such as screen real-estate use and window man-agement can be alleviated. In a controlled experiment, we evaluate the effectiveness of LensMouse in reducing cursor movements for interacting with auxiliary windows. We also consider the concerns involving the view separation that results from introducing such a display-based device. Our results reveal that overall users are more effective with LenseMouse than with auxiliary application windows that are managed either in single or dual-monitor setups. We conclude by presenting other application scenarios that LensMouse could support.
---
paper_title: Dynamo: a public interactive surface supporting the cooperative sharing and exchange of media

paper_content:

In this paper we propose a novel way of supporting occasional meetings that take place in unfamiliar public places, which promotes lightweight, visible and fluid collaboration. Our central idea is that the sharing and exchange of information occurs across public surfaces that users can easily access and interact with. To this end, we designed and implemented Dynamo, a communal multi-user interactive surface. The surface supports the cooperative sharing and exchange of a wide range of media that can be brought to the surface by users that are remote from their familiar organizational settings.
---
paper_title: Virtual reality on a WIM: interactive worlds in miniature

paper_content:

This paper explores a user interface technique which augments an immersive head tracked display with a hand-held miniature copy of the virtual environment. We call this interface technique the Worlds in Miniature (WIM) metaphor. By establishing a direct relationship between life-size objects in the virtual world and miniature objects in the WIM, we can use the WIM as a tool for manipulating objects in the virtual environment. In addition to describing object manipulation, this paper explores ways in which Worlds in Miniature can act as a single unifying metaphor for such application independent interaction techniques as object selection, navigation, path planning, and visualization. The WIM metaphor naturally offers multiple points of view and multiple scales at which the user can operate, all without requiring explicit modes or commands. Informal user observation indicates that users adapt to the Worlds in Miniature metaphor quickly and that physical props are helpful in manipulating the WIM and other objects in the environment.
---
paper_title: PDAs and shared public displays: Making personal information public, and public information personal

paper_content:

We are investigating how people move from individual to group work through the use of both personal digital assistants (PDAs) and a shared public display. Our scenario of this work covers the following activities. First, mobile individuals can create “personal” notes on their PDAs. Second, when individuals meet in real time, they can selectively “publicise” notes by moving them to a shared public display. Third, the group can manipulate personal and public items in real time through both PDAs and the shared public display, where the notes contained on both PDAs and public display are automatically synchronised. Finally, people leave a meeting with a common record of their activity. We describe our SharedNotes system that illustrates how people move through this scenario. We also highlight a variety of problematic design issues that result from having different devices and from having the system enforce a rigid distinction between personal and public information.
---
paper_title: Ubiquitous graphics: combining hand-held and wall-size displays to interact with large images

paper_content:

Ubiquitous Graphics addresses the problem of interacting with very large computer graphics images, for instance an online map or a large digitized painting. It uses a combination of mobile and stationary displays to show both overview and detail. The main image is displayed using a projector or other large traditional display. To access details, the user holds a mobile device in front of the stationary display. Using ultrasonic tracking the smaller display is aligned with the overview, giving access to a corresponding portion of the image in higher resolution. Alternatively the system provides "magic lens" functionality that can show additional information. Users may add free-form annotations and pre-defined graphical objects by interacting directly with the mobile device. In a user study, subjects drew better descriptive maps using the system than an ordinary map application. The system is robust and was demonstrated to several thousand people in a week-long public exhibit.
---
paper_title: E-conic: a perspective-aware interface for multi-display environments

paper_content:

Multi-display environments compose displays that can be at different locations from and different angles to the user; as a result, it can become very difficult to manage windows, read text, and manipulate objects. We investigate the idea of perspective as a way to solve these problems in multi-display environments. We first identify basic display and control factors that are affected by perspective, such as visibility, fracture, and sharing. We then present the design and implementation of E-conic, a multi-display multi-user environment that uses location data about displays and users to dynamically correct perspective. We carried out a controlled experiment to test the benefits of perspective correction in basic interaction tasks like targeting, steering, aligning, pattern-matching and reading. Our results show that perspective correction significantly and substantially improves user performance in all these tasks.
---
paper_title: SyncTap: synchronous user operation for spontaneous network connection

paper_content:

This paper introduces the concept of synchronous user operation, a user interface technique for establishing spontaneous network connections between digital devices. This concept has been implemented in the “SyncTap system”, which allows a user to establish device connections through synchronous button operations. When the user wants to connect two devices, she synchronously presses and releases the “connection” buttons on both devices. Then, multicast packets containing button press and release timing information are sent through the network. By comparing this timing information with locally recorded information, the devices can correctly identify each other. This scheme is simple but scalable because it can detect and handle simultaneous overlapping connection requests. It can also be used to establish secure connections by exchanging public keys. This paper describes the principle, the protocol, and various applications in the domain of ubiquitous computing.
---
paper_title: Multi-display Composition: Supporting Display Sharing for Collocated Mobile Devices

paper_content:

Multi-display composition is a technique that enables several mobile devices to join together over a wireless network to form a larger logical display. This logical display can be created in an ad hoc manner for use when and where it is needed out of a group of users' existing mobile computers. In this work we present a multi-display composition system and discuss our implementation that supports dynamically extending the display across several devices. Furthermore, we present findings from a study of collocated groups of individuals using multi-display composition on two different types of mobile computers. We found mixed results with respect to the effect of the resulting display area. The use of two devices by a pair of participants tended to be rated more favorably than a corresponding group of four devices and participants. Furthermore, while providing additional screen real estate for smaller UMPCs, tablets were rated more favorably when using our system. Finally, we discuss usage themes that emerged from participants' use of the multi-display composition system.
---
paper_title: The effects of interaction technique on coordination in tabletop groupware

paper_content:

The interaction techniques that are used in tabletop groupware systems (such as pick-and-drop or pantograph) can affect the way that people collaborate. However, little is known about these effects, making it difficult for designers to choose appropriate techniques when building tabletop groupware. We carried out an exploratory study to determine how several different types of interaction techniques (pantograph, telepointers, radar views, drag-and-drop, and laser beam) affected coordination and awareness in two tabletop tasks (a game and a storyboarding activity). We found that the choice of interaction technique significantly affected coordination measures, performance measures, and preference - but that the effects were different for the two different tasks. Our study shows that the choice of tabletop interaction technique does indeed matter, and provides insight into how tabletop systems can better support group work.
---
paper_title: Virtual reality on a WIM: interactive worlds in miniature

paper_content:

This paper explores a user interface technique which augments an immersive head tracked display with a hand-held miniature copy of the virtual environment. We call this interface technique the Worlds in Miniature (WIM) metaphor. By establishing a direct relationship between life-size objects in the virtual world and miniature objects in the WIM, we can use the WIM as a tool for manipulating objects in the virtual environment. In addition to describing object manipulation, this paper explores ways in which Worlds in Miniature can act as a single unifying metaphor for such application independent interaction techniques as object selection, navigation, path planning, and visualization. The WIM metaphor naturally offers multiple points of view and multiple scales at which the user can operate, all without requiring explicit modes or commands. Informal user observation indicates that users adapt to the Worlds in Miniature metaphor quickly and that physical props are helpful in manipulating the WIM and other objects in the environment.
---
paper_title: Pick-and-drop: a direct manipulation technique for multiple computer environments

paper_content:

This paper proposes a new field of user interfaces called multi-computer direct manipulation and presents a penbased direct manipulation technique that can be used for data transfer between different computers as well as within the same computer. The proposed Pick-andDrop allows a user to pick up an object on a display and drop it on another display as if he/she were manipulating a physical object. Even though the pen itself does not have storage capabilities, a combination of Pen-ID and the pen manager on the network provides the illusion that the pen can physically pick up and move a computer object. Based on this concept, we have built several experimental applications using palm-sized, desk-top, and wall-sized pen computers. We also considered the importance of physical artifacts in designing user interfaces in a future computing environment.
---
paper_title: The Interactive Workspaces Project: Experiences with Ubiquitous Computing Rooms

paper_content:

The Interactive Workspaces project explores new possibilities for people working together in technology-rich spaces. The project focuses on augmenting a dedicated meeting space with large displays, wireless or multimodal devices, and seamless mobile appliance integration.
---
paper_title: E-conic: a perspective-aware interface for multi-display environments

paper_content:

Multi-display environments compose displays that can be at different locations from and different angles to the user; as a result, it can become very difficult to manage windows, read text, and manipulate objects. We investigate the idea of perspective as a way to solve these problems in multi-display environments. We first identify basic display and control factors that are affected by perspective, such as visibility, fracture, and sharing. We then present the design and implementation of E-conic, a multi-display multi-user environment that uses location data about displays and users to dynamically correct perspective. We carried out a controlled experiment to test the benefits of perspective correction in basic interaction tasks like targeting, steering, aligning, pattern-matching and reading. Our results show that perspective correction significantly and substantially improves user performance in all these tasks.
---
paper_title: Sweep and point and shoot: phonecam-based interactions for large public displays

paper_content:

This paper focuses on enabling interactions with large public displays using the most ubiquitous personal computing device, the mobile phone. Two new interaction techniques are introduced that use the embedded camera on mobile phones as an enabling technology. The "Point & Shoot" technique allows users to select objects using visual codes to set up an absolute coordinate system on the display surface instead of tagging individual objects on the screen. The "Sweep" technique enables users to use the phone like an optical mouse with multiple degrees of freedom and allows interaction without having to point the camera at the display. Prototypes of these interactions have been implemented and evaluated using modern mobile phone technologies. This proof of concept provides a performance baseline and gives valuable insights to guide future research and development. These techniques are intended to inspire and enable new classes of large public display applications.
---
paper_title: SyncTap: synchronous user operation for spontaneous network connection

paper_content:

This paper introduces the concept of synchronous user operation, a user interface technique for establishing spontaneous network connections between digital devices. This concept has been implemented in the “SyncTap system”, which allows a user to establish device connections through synchronous button operations. When the user wants to connect two devices, she synchronously presses and releases the “connection” buttons on both devices. Then, multicast packets containing button press and release timing information are sent through the network. By comparing this timing information with locally recorded information, the devices can correctly identify each other. This scheme is simple but scalable because it can detect and handle simultaneous overlapping connection requests. It can also be used to establish secure connections by exchanging public keys. This paper describes the principle, the protocol, and various applications in the domain of ubiquitous computing.
---
paper_title: PDAs and shared public displays: Making personal information public, and public information personal

paper_content:

We are investigating how people move from individual to group work through the use of both personal digital assistants (PDAs) and a shared public display. Our scenario of this work covers the following activities. First, mobile individuals can create “personal” notes on their PDAs. Second, when individuals meet in real time, they can selectively “publicise” notes by moving them to a shared public display. Third, the group can manipulate personal and public items in real time through both PDAs and the shared public display, where the notes contained on both PDAs and public display are automatically synchronised. Finally, people leave a meeting with a common record of their activity. We describe our SharedNotes system that illustrates how people move through this scenario. We also highlight a variety of problematic design issues that result from having different devices and from having the system enforce a rigid distinction between personal and public information.
---
paper_title: Pick-and-drop: a direct manipulation technique for multiple computer environments

paper_content:

This paper proposes a new field of user interfaces called multi-computer direct manipulation and presents a penbased direct manipulation technique that can be used for data transfer between different computers as well as within the same computer. The proposed Pick-andDrop allows a user to pick up an object on a display and drop it on another display as if he/she were manipulating a physical object. Even though the pen itself does not have storage capabilities, a combination of Pen-ID and the pen manager on the network provides the illusion that the pen can physically pick up and move a computer object. Based on this concept, we have built several experimental applications using palm-sized, desk-top, and wall-sized pen computers. We also considered the importance of physical artifacts in designing user interfaces in a future computing environment.
---

Title: Factors influencing visual attention switch in multi-display user interfaces: a survey

Section 1: INTRODUCTION
Description 1: This section introduces the shift from single personal computers to multi-display user interfaces (MDUIs), highlighting the potential benefits and the challenges related to visual attention switching.

Section 2: TAXONOMIES FOR MDUIs
Description 2: This section reviews existing taxonomies relevant to MDUIs and outlines their relevance to visual attention switching.

Section 3: VA-BASED TAXONOMY OF MDUIs
Description 3: This section introduces a new taxonomy based on visual arrangements (VA) of MDUIs, detailing factors such as display contiguity, angular coverage, content coordination, input directness, and input-display correspondence.

Section 4: Display Contiguity
Description 4: This section explains the different types of display contiguity, classifies existing systems based on these types, and discusses their relevance to visual attention switching.

Section 5: Angular Coverage
Description 5: This section details how the angular coverage of displays affects visual attention switching, classifies relevant systems, and elaborates on the implications for user performance.

Section 6: Content Coordination
Description 6: This section discusses how different types of content coordination across displays influence visual attention, providing classifications and relevant examples.

Section 7: Input Directness
Description 7: This section covers the types of input directness in MDUI systems, their classification, and their impact on visual attention switching.

Section 8: Input-Display Correspondence (IDC)
Description 8: This section explains the various types of input-display correspondences, how they relate to input directness, and their effects on visual attention and performance.

Section 9: CONCLUSIONS
Description 9: This section summarizes the findings, emphasizes the importance of the taxonomy presented, discusses its relevance to practitioners and researchers, and suggests directions for future research.