Projection type display apparatus and multi-vision projection type display apparatus

Claim 2

A projection type display apparatus, comprising: a light source emitting light; a color separator separating the light emitted from said light source into light of three primary colors; a plurality of light valves, each light valve receiving light of one of the three primary colors from said color separator to form a color image; a color synthesizer synthesizing the color images from said plurality of light valves into a single full-color image; a projection lens which enlarges and projects the single full-color image resulting from said color synthesizer; and a half-wave plate placed in at least one path of the light resulting from said color separator, said half-wave plate causing the plane of vibration of the light passing therethrough to rotate a predetermined angle, wherein said half-wave plate is of a disc shape having a diameter and a rectangular effective area through which the light passes to illuminate one of said plurality of light valves, the effective area having a diagonal dimension, and the diameter being equal to or greater than the diagonal dimension.

Claim 3

The projection type display apparatus according to claim 1, wherein said half-wave plate has a light incident surface and a light exiting surface, the surfaces having a coating of non-reflecting material thereon.

Claim 4

A projection type display apparatus according to claim 1, further including an adjusting mechanism causing said half-wave plate to rotate through an angle, wherein said half-wave plate has an optic axis, a light incident surface, and a light exiting surface, said half-wave plate being rotated about a rotational axis which is normal to the light incident surface and passes through the optic axis.

Claim 5

A projection type display system incorporating a plurality of projection type display apparatuses according to claim 1 each of which projects a corresponding image, the system further comprising: a rear projection type screen, and wherein said apparatuses are arranged in matrix form so as to form a multivision projection type display apparatus.

Claim 6

The projection type display system according to claim 4, further including: a chromaticity detector for detecting chromaticity of an image projected on a corresponding screen segment and outputting a detection signal; and a controller for controlling said half-wave plate to rotate through an angle in accordance with the detection signal so that there is substantially no difference in detection signal between chromaticity detectors.

Claim 7

A projection type display system incorporating a plurality of projection type display apparatuses according to claim 1 each of which projects a corresponding image and includes an adjusting mechanism for causing said half-wave plate to rotate through an angle, wherein said half-wave plate has an optic axis and a light incident surface, said half-wave plate being rotated about a rotational axis which is normal to the light incident surface and passes through the optic axis, and wherein said apparatuses are arranged in matrix form so as to form a multivision projection type display apparatus.

Claim 8

The apparatus according to claim 11, wherein three light valves are provided, one for each of the three primary colors, and a half-wave plate is provided on the light incident side of each of said three light valves.

Claim 9

The apparatus according to claim 1, wherein said light source includes an orthogonal parabolic reflector.

Claim 10

The apparatus according to claim 1, wherein said light source includes an elliptical mirror.

Claim 11

A projection type display apparatus comprising: a light source emitting light; a color separator separating the light emitted from said light source into light of three primary colors; a plurality of light valves, each light valve receiving light of one of the three primary colors from said color separator to form a color image; a color synthesizer synthesizing the color images from said plurality of light valves into a single full-color image; a projection lens which enlarges and projects the single full-color image resulting from said color synthesizer; and a half-wave plate placed in at least one path of the light resulting from said color separator, said half-wave plate causing the plane of vibration of the light passing therethrough to rotate a predetermined angle; a chromaticity detector for detecting chromaticity of an image projected on a screen and outputting a detection signal; and a controller for controlling said half-wave plate to rotate though an angle in accordance with the detection signal.

Claim 12

A projection type display apparatus comprising: a light source emitting light; a color separator separating the light emitted from said light source into light of three primary colors; a plurality of light valves, each light valve receiving light of one of the three primary colors from said color separator to form a color image; a color synthesizer synthesizing the color images from said plurality of light valves into a single full-color image; a projection lens which enlarges and projects the single full-color image resulting from said color synthesizer; and a half-wave plate placed in at least one path of the light resulting from said color separator, said half-wave plate causing the plane of vibration of the light passing therethrough to rotate a predetermined angle; a chromaticity detector for detecting chromaticity of an image projected on a screen and outputting a detection signal; and a controller for controlling said half-wave plate to rotate though an angle in accordance with the detection signal.

Claim 13

The apparatus according to claim 10, wherein said half-wave plate has a light incident surface and a light exiting surface, each surface having a coating of non-reflecting material thereon.

Claim 14

The apparatus according to claim 10, further comprising: an adjusting mechanism causing said half-wave plate to rotate though an angle, wherein said half-wave plate has an optic axis, a light incident surface, and a light exiting surface, said half-wave plate being rotated about a rotational axis which is normal to the light incident surface and passes through the optic axis.

Claim 15

The apparatus according to claim 10, wherein said half-wave plate is disc shaped having a diameter and a rectangular effective area through which the light passes to illuminate one of said plurality of light valves, the effective area having a diagonal dimension, and the diameter being equal to or greater than the diagonal dimension.

Claim 16

A projection type display system incorporating a plurality of projection type display apparatuses according to claim 10, each of which projects a corresponding image, the system further comprising: a rear projection type screen, and wherein said apparatuses are arranged in matrix form so as to form a multivision projection type display apparatus.

Claim 17

The apparatus according to claim 10, wherein three light valves are provided, one for each of the three primary colors, and a half-wave plate is provided on the light incident side of each of said three light valves.

Claim 18

The apparatus according to claim 10, further comprising: a memory unit storing desired values of chromaticity for the three primary colors, these desired values being used by said controller for determining the angle of rotation for said half-wave plate.

Claim 19

The apparatus according to claim 10, wherein said light source includes an orthogonal parabolic reflector.

Claim 20

The apparatus according to claim 10, wherein said light source includes an elliptical mirror.

Claim 21

A projection type display system comprising: (a) plurality of projection type display apparatuses arranged in a matrix to form a multivision projection type display apparatus, each of said plurality of projection type display apparatuses projecting a corresponding image and including; (i) a light source emitting a substantially parallel illumination flux, (ii) color separator separating the substantially parallel illumination flux into light of three primary colors including red, green, and blue, (iii) a plurality of light valves, each of said light valves receiving light of a corresponding color to form a color image, (iv) a color synthesizer synthesizing the color images from said plurality of light valves into a single full-color image, (v) a projection lens which enlarges and projects the single full-color image formed by said color synthesizer, and (vi) a half-wave plate placed in at least one path of the light resulting from said color separator, said half-wave plate causing the plane of vibration of the light passing therethrough to rotate through a predetermined angle; (b) a rear projection screen, a section of said screen receiving a full color image from one of said plurality of projection type display apparatuses; (c) a chromaticity detector for detecting chromaticity of an image projected on a corresponding screen segment and outputting a detection signal; and (d) a controller for controlling said half-wave plate to rotate through an angle in accordance with the detection signal.

Claim 22

A projection type display system comprising: (a) plurality of projection type display apparatuses arranged in a matrix to form a multivision projection type display apparatus, each of said plurality of projection type display apparatuses projecting a corresponding image and including; (i) a light source emitting a substantially parallel illumination flux, (ii) color separator separating the substantially parallel illumination flux into light of three primary colors including red, green, and blue, (iii) a plurality of light valves, each of said light valves receiving light of a corresponding color to form a color image, (iv) a color synthesizer synthesizing the color images from said plurality of light valves into a single full-color image, (v) a projection lens which enlarges and projects the single full-color image formed by said color synthesizer, and (vi) a half-wave plate placed in at least one path of the light resulting from said color separator, said half-wave plate causing the plane of vibration of the light passing therethrough to rotate through a predetermined angle; (b) a rear projection screen, a section of said screen receiving a full color image from one of said plurality of projection type display apparatuses; (c) a chromaticity detector for detecting chromaticity of an image projected on a corresponding screen segment and outputting a detection signal; and (d) a controller for controlling said half-wave plate to rotate through an angle in accordance with the detection signal.

Claim 23

The projection type display system according to claim 19, wherein a chromaticity detector and controller are provided for each of said plurality of projection type display apparatuses, said controllers each controlling the half-wave plate of a corresponding projection type display apparatus so that there is substantially no difference between the detection signals resulting from said chromaticity detectors.