Abstract: Display devices are described in which certain structural features prevent cross-talk effects between individual display elements. This ensures sharp delineation between individual display elements which promotes high contrast and sharp displays. These structural features are particularly advantageous for multiplexed display systems so as to simplify circuit arrangements and ensure sharp, high-contrast displays.

Abstract: A particularly important factor limiting the reliability of diode lasers is the catastrophic mirror damage which occurs when the radiated output exceeds a critical value. Experience has shown that this occurs as a result of fluctuations in the drive current, especially in high efficiency diodes. To avoid such damage, a portion of the output radiation from a diode laser, located in the collector circuit of a common emitter drive transistor, is coupled back to a photodetector, located in the base-emitter circuit of the transistor. The resulting negative feedback tends to stabilize the overall operation of the device and maintain the maximum radiated power within safe limits.