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US5225920A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal modulator including a diffuser with plural phase shifting regions

Assignee: Panasonic Holdings Corp
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Filing: 1991-04-04
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Granted: 1993-07-06
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Expires: 2011-04-04
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Abstract

Abstract Light emitted from a coherent light source undergoes fine adjustment of its polarizing direction by a polarizing device and is directed to a liquid crystal device through a collimating optical system. The polarizing device is capable of fine-adjusting the polarizing direction in accordance with the wavelength of the incident light, thereby providing a high contrast ratio. When an image is recorded by holography using such a liquid crystal spacial light modulator, it is possible to obtain an image of high quality.

Inventors

  • 👤 Kenichi Kasazumi
  • 👤 Makoto Kato
  • 👤 Ikunori Kobayashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 15:43
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528; G03; G03H; G03H1/00; G03H1/04; G03H1/16; G03H1/26; G03H1/268; G03H2210/00; G03H2210/10; G03H2210/12; G03H2210/20; G03H2210/22; G03H2222/00; G03H2222/31; G03H2223/00; G03H2223/13; G03H2225/00; G03H2225/55

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 138 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device.
Claim 2
Dependent Claim 138 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device.
Claim 3
Dependent Claim 26 words
A liquid crystal spacial light modulator according to claim 1, wherein a polarizing plate is provided on an outgoing light side of the liquid crystal device.
Claim 4
Dependent Claim 43 words
A liquid crystal spacial light modulator according to claim 1, wherein the phase retardation of the phase shift regions of the diffuser is 0, π/2, π or 3 π/2, and the phase difference between adjacent phase shift regions of the diffuser is π/2.
Claim 5
Dependent Claim 42 words
A liquid crystal spacial light modulator according to claim 1, wherein the phase retardation of the phase shift regions of the diffuser is 0, π/3 or 2 π/3, and the phase difference between adjacent phase shift regions of the diffuser is π/3.
Claim 6
Dependent Claim 35 words
A liquid crystal spacial light modulator according to claim 1, wherein a glass plate with anti-reflection coating on an outgoing light surface thereof is provided on an outgoing light side of the liquid crystal device.
Claim 7
Dependent Claim 89 words
A liquid crystal spacial light modulator according to claim 1, wherein a glass plate is provided on an outgoing light surface of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the outgoing light surface of the transparent plate being slanted with respect to the incident light surface thereof, and the glass plate being disposed so that the outgoing light surface thereof is slanted with respect to the outgoing light surface of the liquid crystal device.
Claim 8
Dependent Claim 87 words
A liquid crystal spacial light modulator according to claim 1, wherein a glass plate is provided on an outgoing light surface of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the incident light and outgoing light surfaces of the transparent plate being parallel to each other, and the glass plate being disposed so that the outgoing light surface thereof is slanted with respect to the outgoing light surface of the liquid crystal device.
Claim 9
Dependent Claim 235 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device; wherein a glass plate with anti-reflection coating on an outgoing light surface of the glass plate is provided on an outgoing light side of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the outgoing light surface of the transparent plate being slanted with respect to the incident light surface of the transparent plate, and the glass plate being disposed so that the outgoing light surface of the glass plate is slanted with respect to the outgoing light surface of the liquid crystal device.
Claim 10
Dependent Claim 235 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device; wherein a glass plate with anti-reflection coating on an outgoing light surface of the glass plate is provided on an outgoing light side of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the outgoing light surface of the transparent plate being slanted with respect to the incident light surface of the transparent plate, and the glass plate being disposed so that the outgoing light surface of the glass plate is slanted with respect to the outgoing light surface of the liquid crystal device.
Claim 11
Dependent Claim 230 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device; wherein a glass plate with anti-reflecting coating on an outgoing light surface of the glass plate is provided on an outgoing light side of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the incident light and outgoing light surfaces of the transparent plate being parallel to each other, and the glass plate being disposed so that the outgoing light surface of the glass plate is slanted with respect to the outgoing light surface of the liquid crystal device.
Claim 12
Dependent Claim 230 words
A liquid crystal spacial light modulator comprising: a coherent light source; a polarizing device capable of fine-adjusting the polarizing direction of the light emitted from the coherent light source; a collimating optical system into which the light with its polarizing direction adjusted by the polarizing device is introduced; a liquid crystal device into which the light passing through the collimating optical system is introduced for transmission therethrough and which modulates the intensity of the transmitting light in accordance with image data; and a diffuser which has a plurality of phase shift regions arranged at a prescribed pitch and is disposed on an incident light side of the liquid crystal device, at least two of the plurality of phase shift regions of the diffuser being arranged in a manner to correspond to one pixel of the liquid crystal device; wherein a glass plate with anti-reflecting coating on an outgoing light surface of the glass plate is provided on an outgoing light side of the liquid crystal device, the glass plate consisting of a transparent plate having an outgoing light surface and an incident light surface, the incident light and outgoing light surfaces of the transparent plate being parallel to each other, and the glass plate being disposed so that the outgoing light surface of the glass plate is slanted with respect to the outgoing light surface of the liquid crystal device.

References Cited (Backward Citations)

US3736047A Cited
US4505547A Cited
US4715686A Cited
US5148302A Cited
JPH01254990A Cited
JPH01302376A Cited
US5046827A Cited
US5046827C1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-07-05 1997-01-04 1997-07-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-07-05 2001-01-04 2001-07-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-07-05 2005-01-04 2005-07-06 $7700.00 Window Closed / Lapsed

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