Projection type liquid crystal display apparatus

A projection type liquid crystal display apparatus comprising:

• a light source;
• a liquid crystal display device which receives a light beam emitted from the light source and forms an image light beam, the liquid crystal display device including a liquid crystal layer sandwiched between a pair of substrates, and electrodes for controlling an electro-optical effect of the liquid crystal layer;
• and
• a projection lens which receives the image light beam and directs the image light beam onto a screen,
• wherein the projection lens and the liquid crystal display device are disposed to satisfy the relationship:
• .theta..sub.LC-max -1.degree..ltoreq..theta..sub.LENS .ltoreq..theta..sub.LC-max +1.degree.,
• where .theta..sub.LENS is a collection angle of the projection lens and .theta..sub.LC-max is a maximum viewing angle of the liquid crystal display device, at which a contrast ratio of the image light beam emitted through the projection lens CR.sub.PROJ is equal to a prescribed contrast ratio CR.sub.TARGET,
• and CR.sub.PROJ is calculated by the following equation:
• CR.sub.PROJ =.intg.T.sub.max (.theta..sub.LC, u, V.sub.LC-max).multidot.t(.theta..sub.LC) d.theta..sub.LC /.intg.T.sub.min (.theta..sub.LC, u, V.sub.LC-min).multidot.t(.theta..sub.LC) d.theta..sub.LC,
• where u=d.multidot..DELTA.n/.lambda.;
• d is a thickness of the liquid crystal layer;
• .DELTA.n is a birefringence of a liquid crystal material of the liquid crystal layer;
• .lambda. is a wavelength of the light beam;
• t(.theta.) is a luminance at an angle .theta. of the light beam incident onto the liquid crystal display device;
• .theta..sub.LC is a viewing angle of the liquid crystal display device with respect to the normal to a display plane of the liquid crystal display device;
• V.sub.LC-max is a voltage applied to the liquid crystal layer for maximizing a transmittance of the liquid crystal display device;
• V.sub.LC-min is a voltage applied to the liquid crystal layer for minimizing the transmittance of the liquid crystal display device;
• .intg.T.sub.max (.theta..sub.LC, u, V.sub.LC-max) is a maximum transmittance at .theta..sub.LC ;
• and .intg.T.sub.min (.theta..sub.LC, u, V.sub.LC-max) is a minimum transmittance at .theta..sub.LC.