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multiple LCD cells is used. Since a single panel is used, it is necessary to scan the panel with the primary
colors to obtain a color picture. A LCD is a light valve which allows more or less light through it, depending
on the applied voltage.
The LCD used in most projectors and direct view LCD TVs uses a transmissive type of LCD. Light is
projected to pass through the LCD panel. One of the disadvantages of this type of system is that the
electronics to control the LCD cells limit the surface area in which light can pass. This limits the resolution
of the picture and brightness.
The Reflective type of LCD, like the one used in the LCOS, has the electronics beneath the LCD cells,
allowing greater resolution. The LCD cells are turned On, switching the individual cells. Beneath each cell
is a reflective surface. The amount of light reflected from each cell depends on the applied voltage. Since
the LCD may be illuminated by all three primary colors at one time, several cells are addressed at once.
2004-08-09 |
ACEC
