Hughes JVC 200, Service Manual

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Chapter 2---System Description
2.4 Image Light Amplifier Technology
Section 2.2 explained how the various units, including the ILA
®
assemblies, in the Optical System work together to produce the
image on the screen. This section focuses mainly on how the
ILA
®
assembly itself works.
An Image Light Amplifier ( ILA
®
) assembly ( Figure 2-18 ) is a
device that uses low-intensity images to modulate a high-intensity
light through a liquid crystal layer. It is the key component in
producing very bright, high resolution images from Hughes-JVC
large-screen projectors.
Figure 2-18. The Hughes-JVC Image Light Amplifier
®
.
Optically, there are two sides to an ILA
®
assembly with a light
blocking layer in the center. On the input side there is a photo-
conductive layer where the image from a CRT is focused through
a relay lens. This image is electrostatically coupled through the
light-blocking layer and mirror to a liquid crystal layer on the output
side of the
ILA
®
assembly.
Model 200 Service Manual 2-63