Wednesday, February 25, 2015

Sony's Consumer Electronics Mojo



Tuesday, February 3, 2015

Engineering vs. Physics






Tuesday, January 6, 2015

More on Display-Centric Movies

I had done a couple of posts on movies where display technology was central to the movie plot (here and here), naming a top ten. Of the ten, there were many other movies that I cold have named e.g. Star Wars, Star Trek, The Matrix, Total Recall, The Avengers); but for better or worse I chose the ten that I did. I recently saw a YouTube posting that I may have omitted a big one... 2001 A Space Odyssey.

The premise of the YouTube video is that the monolith (the 1 x 4 x 9 object that appears at the dawn of human intelligence) is actually a widescreen TV set on end. Although videos are not project on the monolith, it serves as a teaching tool for proto-humans early on in the movie, a means of conveying ideas. Later, when a duplicate appears orbiting Jupiter, it appears as a doorway to other worlds and it eventually transforms into the ultimate immersive display. In function, it exhibits the best of what TV is supposed to do. In physical form, the 4:9 aspect ratio (2.25 width to height) falls beyond the old 1.85 US widescreen standard and just short of the current 2.33 standard. The thickness is greater than what you would currently get in a TV but perhaps it has really good built in sound.

On a tangential subject, over the holidays I saw "The Hobbit, the Battle of the 5 Armies" in 3D. Thankfully, filmmakers have gotten out of the habit of throwing things out of the screen at you with their new-found toy in 3D and the use of 3D was quite acceptable. However, the thing that 3D was really supposed to bring, increased realism was very much lacking in the presentation. The digital projection was sharp and crisp as it is supposed to be, but it gave the overall effect of artificiality. Rather than being as looking through a window, the digital projection makes it painfully obvious the image is a projection. In a recent edition of "The Economist" director Quentin Tarantino describes digital cinema as "The death of Cinema as we know it". The Economist article goes on to state, "Digital projectors cannot match the sheer detail of a pristine 35mm print, nor its rich contrast between the deepest shadows and brightest highlights." However, for me, it was not the lack of detail but the digitized edges (not quite jaggies)that gave a fake feel to the image. Seemingly, this is something that could be corrected with software, however the function of most image enhancement software is edge sharpening rather than edge blurring. Perhaps the role of image post processing in cinema should be re-thought. In any case, as in my 10th selection for display centric movies, "Here's to Film".

Wednesday, November 26, 2014

OLEDS and Why Your Old CRT TV still Works

Two stories about TV, not directly about OLED, that I will tie together down below. This note is about OLEDs. Although you can not buy a LCD TV that was made in the US, the active matrix LCD was actually invented in the US, in Pittsburgh by Westinghouse. Westinghouse was a prominent TV brand that was developing new technology. Westinghouse did not survive in the TV business long enough to capitalize on their invention because they had a problem at their factory. It seems a worker replaced a steel mesh filter in their water reclaim system with a copper coated steel mesh filter. That put just enough copper into the wash water and just enough wash water residue was left on the TV screen to serve as a phosphor poison. The TV tubes that the Westinghouse factory was making would go dark after about 6 months of use. The resultant recall of half a year’s production put Westinghouse out of the TV business. Parts per billion of copper put them out of business.

Another major brand of TV in those times was General Electric (GE). Although GE made glass for things such as light bulbs and such, GE bought their glass for CRT tubes from others. In addition to making glass, GE had an array of materials technologies including silicones and polycarbonate. At one point, in order to put downward pressure on glass prices, GE threatened to develop a polycarbonate CRT bulb. The glassmakers looked at the threat and determined that although such a product was possible and did have some advantages relative to glass, the product would only last about a year before there was enough inward migration of atmospheric gas to render the polycarbonate CRT non-functional.

The point of both stories is that emissive technologies tend to be sensitive to the most minute amount of contaminants. That is why some of the companies developing OLED technology concentrate on an ultra-clean manufacturing environment. It is also why the other key to OLED’s future is hermaticity. In a CRT, glass provided an absolute hermetic environment. The CRT was made in a clean environment, the inside of the tube, where the phosphors were, was maintained in high vacuum. Further a sacrificial barium “getter” was deposited on the inside of the tube to bind any stray oxygen that was left over from manufacture.

So, the phosphors did their thing in an absolutely pristine environment that was maintained as long as the tube continued to hold its vacuum, which is tantamount to forever for a consumer product. In terms of product chemistry, the environment virtually eliminated any alternative pathways that could be formed between the phosphor in its elevated state and when it drops back down to its base state by emitting a photon. The industry employed other tricks, such as moving to higher and higher voltage phosphors. This brought the product to the point where the phosphor aging was no longer the primary aging limitation but metallization of the glass from decades of electron bombardment.
