Illumination unit for liquid crystal projection display apparatus and liquid crystal display apparatus having it used

A projection type liquid crystal display unit comprising:

• a light source for emitting light;
• a reflector for focusing the light from said light source, the reflector having a shape which satisfies the following conditional expression:
• D.gtoreq.4f.gtoreq.0.75.times.D
• where D indicates an aperture of the reflector and f indicates a focal length of the reflector;
• a liquid crystal display element which is illuminated by the light emitted from said light source, and;
• a projection lens for enlarging and projecting an image on said liquid crystal display element onto a screen.

A projection type liquid crystal display comprising:

• a light source for emitting light,
• a reflector for focusing and emitting the light from the light source onto a liquid crystal display element which is illuminated by the light from said light source,
• a projection lens for enlarging and projecting an image on said liquid crystal display element onto a screen, and
• a dichroic reflecting mirror which is formed in said light source by a dichroic film which transmits thermic rays and reflects visible rays.

A projection type liquid crystal display unit comprising:

• a light source for emitting light,
• a liquid crystal display element which is illuminated by light emitted from said light source,
• a projection lens for enlarging and projecting an image from said liquid crystal display element onto a screen;
• and,
• an elliptical reflector for focusing light from the light source, the reflector having a shape which satisfies the following conditional expression:
• (D.times.L)/(D+y)<f<(D.times.L)/(D+y)
• where L indicates a distance from a top of the reflector to the liquid crystal display element, f is a focal length of the reflector, D is an aperture of the reflector, and y is a diagonal length of the liquid crystal display element.

A projection type liquid crystal display unit comprising:

• a light source for emitting light,
• a reflector for focusing the light from the light source,
• a condenser lens for focusing the light from the reflector,
• a liquid crystal display element which is to be illuminated by said focused light,
• a projection lens for enlarging and projecting an image from said liquid crystal display element onto a screen, and
• the reflector having a shape which satisfies the following conditional expression:
• (D-LO)/(D+y)<f.sub.CL <(D-LO)/(D-y)
• where LO indicates a distance from the condenser lens to the liquid crystal display element, f.sub.CL is a focal length of the condenser lens, D is an aperture of the condenser lens, and y is a diagonal length of the liquid crystal display element.