Ricoh KW5708, Service Training

Page: 49 / 61

Slide 49
Terms and Definitions - 2

Dichroic Mirror

A dichroic mirror reflects light of a certain frequency range
and allows all other light to pass through.

LCD projectors contain two of these mirrors, to split the light
up into three beams.

Polarized Light

Light waves oscillate in the same way as sound waves.

If the waves oscillate in one plane only, the light is said to
be polarized.

Light reflected by a polarizing screen is polarized, and is
brighter than light reflected from a non-polarizing screen.

Residual Image

When an image on a display changes, a residual image of
the previous image can remain for some time.

In serious cases, it can last for more than 1 minute.

LCD panels normally do not have this problem.