Tunable examples of a type of these devices include the Berek compensator and the Soleil-Babinet compensator. Spatial hole burning in continuous wave lasers can be avoided by placing two of these devices on either side of the gain medium, a process called a "twisted-mode tec
Tunable examples of a type of these devices include the Berek compensator and the Soleil-Babinet compensator. Spatial hole burning in continuous wave lasers can be avoided by placing two of these devices on either side of the gain medium, a process called a "twisted-mode technique." An alternative to one type of these devices is the Fresnel rhomb. The amount of retardation is a multiple of two pi larger in a "multiple-order" one of these devices than in a "zero-order" one of these devices. In one type of these devices, the waves propagating parallel to the "fast axis" acquire a phase shift of pi over 2 with respect to waves propagating parallel to the "slow axis," because the index of refraction is split into "ordinary" and "extraordinary" components. A birefringent crystal which converts linearly polarized light to circularly polarized light is an example of, for 10 points, what type of optical device which comes in "half" and "quarter" types?