Rear Projection

Rear Projection TVs project an image onto the screen from the back of
the TV. It’s a bit like having a miniature cinema inside your TV. The
upside of this is that they are pretty cheap to manufacture, but the
downside is that they have poor viewing angles and a big and bulky.
Modern rear projection
televisions are much smaller than older models, but they remain bigger
and bulkier than the LCD and Plasma
displays that are increasingly dominating the market. These modern rear
projection televisions use one of two technologies;  LCD projector
or DLP
(Digital Light Processing) projector.

LCD projector TV’s project light from the back of the TV through liquid
crystals that are manipulated by electical signals to control how
much light passes through them. DLP
projection televisions use a digital micromirror device that is made up
of a larage matrix of mirrors. The mirrors are then rotated to control
how much light is projected on the display. Color is produced in one of
two ways, either with a spinning color wheel that has filters for red
green and blue, or by using three separate
chips, each of which produces the red, green or blue primary colors.

Rear projection televisions are generally much less expensive to
produce than modern flat panel displays, either LCD or Plasma.
DLP
projectors in particular do an excellent job of producing deep blacks
and accurate colors. They also have very good viewing angles. The major
negative of rear projection televisions is their size. Although they
have become slimmer in recent years, they are still generally larger,
and in particular thicker, than LCD and Plasma televisions, and cannot
be mounted on walls. This has
made them less popular than other television technologies.