Liquid crystal projection apparatus

Claim 2

A liquid crystal color projection apparatus comprising: - a light source (1); - dichroic mirrors (4, 9) for separating light, supplied from said light source, into red, green, and blue beams; - transmission type liquid crystal panels (7, 12, 15), respectively arranged on optical paths of the three color beams separated by said dichroic mirrors, for forming images corresponding to the three color beams; - beam mixing means (13, 17) for mixing image beams from said transmission liquid crystal panels to reproduce a color image; characterized by - at least two parallel side plates (35, 36) having plural pairs of engaging portions (38a, 38b, 39a, 39b, etc.), arranged at symmetrical positions, for fixing said dichroic mirrors and said liquid crystal panels at predetermined positions; and - bar members (40a, 40b, etc.), each having two end portions fixed to one pair of engaging portions of said side plates for fixing and holding two arbitrary end portions of each of said dichroic mirrors (4, 9) and liquid crystal panels (7, 12, 15) thereon.

Claim 3

An apparatus according to claim 1, wherein said dichroic mirrors and said liquid crystal panels are fixed to said bar members such that incident surfaces, of said dichroic mirrors and said liquid crystal panels on which light from said light source is incident, are in direct contact with said bar members (40a, 40b).

Claim 4

An apparatus according to claim 1 or 2, wherein said dichroic mirrors and said liquid crystal panels are fixed to said bar members with a pair of fastening metal plates (42, 43) clamping said bar members (40a, 40b, etc.).

Claim 5

An apparatus according to claim 1, 2 or 3, wherein said bar members are round bars.

Claim 6

An apparatus according to claim 1, 2, 3 or 4, wherein said beam mixing means is a dichroic mirror or prism.

Claim 8

An apparatus according to claim 6, further comprising a screen (120) mounted while an end portion thereof located in an inclination direction of the angle a is inclined toward said projection lens at an angle equal to the angle a.

Claim 9

An apparatus according to claim 6 or 7, wherein the optical paths of the three color beams from said dichroic mirrors are inclined at an angle not more than an angle corresponding to an inclination, obtained by dividing a distance corresponding to 1/2 an image projected at a predetermined position on said screen by a projection distance, with respect to an axis perpendicular to the panel surface of each of said liquid crystal panels and said projection mirror is inclined at the angle a to set a base line or a lower line of a projected image to be horizontal with respect to lens center.

Claim 10

An apparatus according to claim 6, wherein said projection lens comprises an L-shaped mirror barrel (109a) and front and rear lenses (109b, 109c) respectively fitted in two opening portions of said mirror barrel, said projection mirror is arranged at a bent portion (109d) of said L-shaped mirror barrel, said rear lens (109c) is inclined at the predetermined angle in the same inclination direction of each of said liquid crystal panels with respect to the optical path of the image beam transmitted through each of said liquid crystal panels and the center of said front lens (109b) is inclined at the predetermined angle in the same inclination direction of each of said liquid crystal panels with respect to an optical path of a beam reflected by said projection mirror (108).

Claim 12

An apparatus according to claim 10, wherein tongue pieces (48a to 48d) are formed at two end portions of said holding member for form gaps between said tongue pieces and a main body of said holding member so as to insert said bar members (40a, 40b).

Claim 14

An apparatus according to claim 12, wherein a mixing/projecting optical system for the separated three color beams is arranged such that the number of times of transmission by said beam mixing means is set to be not more than one, and said parallax correcting plate (132) is arranged in an optical path in which the number of times of transmission is 0.

Claim 15

An apparatus according to claim 12, wherein said parallax correcting plate is constituted by a transparent plate consisting of the same material as that for said beam mixing means and having the same thickness as that thereof, and is arranged in the same direction as that of said beam mixing means and at the same inclination as that thereof.

Claim 16

An apparatus according to claim 12, wherein said parallax correcting plate is arranged at an angle smaller than an angle at which said beam mixing means is arranged.

Claim 17

An apparatus according to claim 12, wherein said parallax correcting plate has a thickness larger than that of said beam mixing means.

Claim 18

An apparatus according to claim 12, wherein said parallax correcting plate has a refractive index larger than that of said beam mixing means.

Claim 20

An apparatus according to claim 18, wherein said linear polarization rotating means (232) is arranged between said light source and said polarized beam splitting means to be perpendicular to an optical axis, and when the transmitted linearly polarized beam (P wave) whose polarization direction is rotated through 45 by said linear polarization rotating means is reflected at 180° by said reflector (202) to be incident on and transmitted through said linear polarization rotating means again, the polarization direction is further rotated through 45°, and the transmitted linearly polarized beam is incident on said polarized beam splitting means to be reflected in a direction perpendicular to the optical axis of the natural light so as to be mixed with the reflected linearly polarized beam (S wave).

Claim 22

An apparatus according to claim 20, wherein said optical interlace unit comprises an optical flat plate glass (333) and a driving source (334) for reciprocating said flat plate glass in the optical path between two predetermined angles corresponding to an odd field and an even field in synchronism with the field signal.

Claim 23

An apparatus according to claim 20, wherein said optical interlace unit comprises an optical glass (333) inclined by an angle corresponding to either an odd field or an even field, and a driving source (334) for rotating said glass in synchronism with the field signal to move said glass into and out of the optical path.

Claim 24

A liquid crystal projection apparatus comprising: - a light source (1); - a transmission type liquid crystal panel (7, 12, 15) for receiving light from said light source and generating an image; - two parallel side plates (35, 36) having plural pairs of engaging portions (38a, 38b, 39a, 39b, etc.), arranged at symmetrical positions, for fixing said liquid crystal panel at a predetermined position; and - a bar member (40a, 40b, etc.), having two ends fixed to one of said pairs of engaging portions of said side plates, for fixing and holding two arbitrary end portions of a dichroic mirror and those of said liquid crystal panel (7, 12, 15).

Claim 25

A liquid crystal projection apparatus comprising: - a light source (1); - a transmission type liquid crystal panel (7, 12, 15) for receiving light from said light source and generating an image; - two parallel side plates (35, 36) having plural pairs of engaging portions (38a, 38b, 39a, 39b, etc.), arranged at symmetrical positions, for fixing said liquid crystal panel at a predetermined position; and - a bar member (40a, 40b, etc.), having two ends fixed to one of said pairs of engaging portions of said side plates, for fixing and holding two arbitrary end portions of a dichroic mirror and those of said liquid crystal panel (7, 12, 15).

Claim 26

A liquid crystal projection apparatus comprising: - a transmission type liquid crystal panel (107) for generating an image; - a light source (101) for causing a light source beam to be incident on a panel surface of said liquid crystal panel at a predetermined incident angle 0 with respect to an axis perpendicular to the panel surface; - a projection mirror (108) for reflecting an image beam, transmitted through said liquid crystal panel, at a predetermined angle a within the same plane of incidence; and - a projection lens (109) whose axis is inclined by the angle a to cause the optical axis to be incident on an axis of a beam reflected by said projection mirror at a predetermined incident angle.

Claim 27

A liquid crystal projection apparatus comprising: - a transmission type liquid crystal panel (107) for generating an image; - a light source (101) for causing a light source beam to be incident on a panel surface of said liquid crystal panel at a predetermined incident angle 0 with respect to an axis perpendicular to the panel surface; - a projection mirror (108) for reflecting an image beam, transmitted through said liquid crystal panel, at a predetermined angle a within the same plane of incidence; and - a projection lens (109) whose axis is inclined by the angle a to cause the optical axis to be incident on an axis of a beam reflected by said projection mirror at a predetermined incident angle.

Claim 28

A liquid crystal projection apparatus comprising: - a pair of side plates (35, 36) arranged parallel to sandwich optical components such as a liquid crystal panel; - a pair of bar members (40a, 40b), each having two ends held by said side plates; - a holding member (142), having fixing portions (47a, 47b) extending from said side plates for fixing and holding two end portions of an incident surface of said liquid crystal panel on said bar members (40a, 40b) so as to allow said liquid crystal panel to be slidable in a direction parallel to said bar members; and - brackets (53a, 53b) arranged to oppose said fixing portions of said holding member and fixed to said side plates after said liquid crystal panel is moved and adjusted in directions perpendicular and parallel to said bar members.

Claim 29

A liquid crystal projection apparatus comprising: - a pair of side plates (35, 36) arranged parallel to sandwich optical components such as a liquid crystal panel; - a pair of bar members (40a, 40b), each having two ends held by said side plates; - a holding member (142), having fixing portions (47a, 47b) extending from said side plates for fixing and holding two end portions of an incident surface of said liquid crystal panel on said bar members (40a, 40b) so as to allow said liquid crystal panel to be slidable in a direction parallel to said bar members; and - brackets (53a, 53b) arranged to oppose said fixing portions of said holding member and fixed to said side plates after said liquid crystal panel is moved and adjusted in directions perpendicular and parallel to said bar members.

Claim 30

A liquid crystal color projection apparatus comprising: - a light source (1); - dichroic mirrors (4, 9) for separating light, supplied from said light source, into red, green, and blue beams; - transmission type liquid crystal panels (7, 12, 15), respectively arranged on optical paths of the three color beams separated by said dichroic mirrors for forming images corresponding to the three color beams; - beam mixing means (13, 17) for mixing image beams from said transmission liquid crystal panels to reproduce a color image; and - a parallax correcting plate (132) arranged in the optical path of each of the three color beams to equalize the numbers of times that the separated three color beams are transmitted through said beam mixing means (13, 17).

Claim 31

A liquid crystal color projection apparatus comprising: - a light source (1); - dichroic mirrors (4, 9) for separating light, supplied from said light source, into red, green, and blue beams; - transmission type liquid crystal panels (7, 12, 15), respectively arranged on optical paths of the three color beams separated by said dichroic mirrors for forming images corresponding to the three color beams; - beam mixing means (13, 17) for mixing image beams from said transmission liquid crystal panels to reproduce a color image; and - a parallax correcting plate (132) arranged in the optical path of each of the three color beams to equalize the numbers of times that the separated three color beams are transmitted through said beam mixing means (13, 17).

Claim 32

A liquid crystal projection apparatus comprising: - light source means (230) including a reflector (202) such as a rotating parabolic mirror; - polarized beam splitting means (233), arranged on an optical axis of a parallel focused beam from said light source means, for splitting the focused beam into a transmitted linearly polarized beam (P wave) and a reflected linearly polarized beam (S wave); - reflecting means (237) for reflecting the transmitted linearly polarized beam at 180° to cause the transmitted linearly polarized beam to be incident on said beam splitting means again; and - linear polarization rotating means for rotating, through 45` , a polarizing direction of a transmitted linearly polarized beam (P wave) which is reflected by said reflecting means at 180° again and transmitted through said polarized beam splitting means again, - wherein said linear polarization rotating means is arranged between said light source means and said polarized beam splitting means to be perpendicular to an optical axis, and when the transmitted linearly polarized beam (P wave) whose polarization direction is rotated through 45° by said linear polarization rotating means is reflected at 180° by said reflector to be incident on and transmitted through said linear polarization rotating means again, the polarization direction is further rotated through 45°, and the transmitted linearly polarized beam is incident on said polarized beam splitting means to be reflected in a direction perpendicular to the optical axis of the natural light so as to be mixed with the reflected linearly polarized beam (S wave).

Claim 33

A liquid crystal projection apparatus comprising: - light source means (230) including a reflector (202) such as a rotating parabolic mirror; - polarized beam splitting means (233), arranged on an optical axis of a parallel focused beam from said light source means, for splitting the focused beam into a transmitted linearly polarized beam (P wave) and a reflected linearly polarized beam (S wave); - reflecting means (237) for reflecting the transmitted linearly polarized beam at 180° to cause the transmitted linearly polarized beam to be incident on said beam splitting means again; and - linear polarization rotating means for rotating, through 45` , a polarizing direction of a transmitted linearly polarized beam (P wave) which is reflected by said reflecting means at 180° again and transmitted through said polarized beam splitting means again, - wherein said linear polarization rotating means is arranged between said light source means and said polarized beam splitting means to be perpendicular to an optical axis, and when the transmitted linearly polarized beam (P wave) whose polarization direction is rotated through 45° by said linear polarization rotating means is reflected at 180° by said reflector to be incident on and transmitted through said linear polarization rotating means again, the polarization direction is further rotated through 45°, and the transmitted linearly polarized beam is incident on said polarized beam splitting means to be reflected in a direction perpendicular to the optical axis of the natural light so as to be mixed with the reflected linearly polarized beam (S wave).

Claim 34

A liquid crystal projection apparatus comprising: - a light source (301); - a liquid crystal panel (307, 312, 315) as an image display carrier for receiving light from said light source and generating an image subjected to non-interlaced display in accordance with a field signal of a standard TV signal; - a projection lens (319) for enlarging and projecting an image beam from said liquid crystal panel on a screen; and - an optical interlace unit (332), arranged in an optical path extending from said liquid crystal panel for translating an optical axis by a predetermined amount in synchronism with the field signal.

Claim 35

A liquid crystal projection apparatus comprising: - a light source (301); - a liquid crystal panel (307, 312, 315) as an image display carrier for receiving light from said light source and generating an image subjected to non-interlaced display in accordance with a field signal of a standard TV signal; - a projection lens (319) for enlarging and projecting an image beam from said liquid crystal panel on a screen; and - an optical interlace unit (332), arranged in an optical path extending from said liquid crystal panel for translating an optical axis by a predetermined amount in synchronism with the field signal.