Silicon Graphics Presenter, Руководство пользователя

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Appendix A
A. Liquid Crystal Display (LCD) Technology
This section contains technical information on liquid crystal display
technology.
Display
The key component in the Indy Presenter is the active matrix display
module. It is composed of twisted nematic liquid crystal material,
sandwiched between two sheets of glass, activated by electronic switches
deposited on the inner surface of the glass. The electronic switches vary the
voltage applied to the liquid crystal and thus change its transparency.
Vertical stripes of alternating red (R), green (G), and blue (B) colored filters
made of organic dyes are located on the front glass plate, under a transparent
indium tin oxide electrode. The intersection of each of these colored stripes
with an active electronic element forms a subpixel of that color.
The electronic switches on the back glass are known as thin film transistors
(TFTs) and are addressed in an x-y matrix from integrated circuit drivers.
These drivers, bonded to flexible circuits by tape automated bonding (TAB)
techniques, are located around the display edges in the plane of the glass
package. Conductive thermoplastic adhesive strips connect the TAB tapes
and the electrodes on the TFT glass panel. The assembly is held together by
a stamped metal bezel.
A backlight assembly behind the display glass consists of an acrylic light
pipe, plastic diffuser, and cold cathode fluorescent (CCF) tubes. Four tubes,
two at the top and two along the bottom, produce a bright image with high
color saturation.
In Silicon Graphics, Inc.’s implementation, the acrylic light pipe is attached
to a rear door that is removable by the user, so the display can be used with