6. Other projection techniques

6.1 ILA spotlights

The ILA (image light amplifier) projector is the fruit of collaboration between JVC and Hughes Aircraft. ILA technology separates the image generation part from the illumination part, which provides the source of the amplification. For image generation, a cathode-ray tube is used, whose image is transferred to the electro-optical device, which consists of a reflective liquid-crystal screen without an addressing matrix, but with a layer of photosensitive elements acting as variable resistors, which modulate the voltage locally on the liquid crystal according to the light level received from the CRT. This device, which works by reflection, receives a command at each point in the form of a light signal to open or close the pixel. A powerful xenon lamp illuminates the...