US4611245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Real-time ultra-high resolution image projection display using laser-addressed liquid crystal light valve
Assignee: United States Department of the Navy
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Filing: 1984-10-29
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Granted: 1986-09-09
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Expires: 2004-10-29
Abstract
Abstract A wide screen display enables a number of viewers the simultaneous viewingf rapidly updated data in real time at video rates. A beam of coherent radiation from a laser is modulated at video rates in an acousto-optic modulator. The modulated beam is fed to an X-scanner that imparts an acousto-optic displacement of the modulated beam in the X-direction. A Y-scanner is aligned to receive the X-scanned modulated beam and imparts an acousto-optic reciprocal displacement of the beam so that the video modulated beam is displaced in both the X- and Y-directions. A liquid crystal light valve is disposed to receive the X and Y displaced modulated beam so that it scans the surface of the light valve to stimulate the photosensor layers within. This causes the impression of a replica voltage pattern on a bi-refringent liquid crystal in the valve. A high intensity lamp projects a high intensity incoherent light beam onto the liquid crystal light valve via a polarizing biprism. Since the bi-refringent liquid crystal has been modulated by the X- and Y-scanned modulated coherent beam, a corresponding image is reflected from the bi-refringent liquid crystal and onto the screen. The acousto-optic modulation X-scan and Y-scan occur at much higher rates and with greater control than conventional arrangements so that the resolution of two about 2,000 lines at a video rate is possible. The real-time display provides a number of viewers with a more realistic image so that responsive decisions and actions may be taken.
Inventors
- 👤 John Trias
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:53
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/74; H04N5/7416; H04N5/7441
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
266 words
An improved apparatus for displaying real-time, ultra-high resolution projected images on a distant screen in accordance with video image signal rates comprising: a laser providing a beam of coherent light; means located to receive the beam of coherent light for modulating it at video image signal rates; means disposed to receive the video rate modulated coherent light beam from the modulating means for reciprocally imparting a scan thereof in an X-direction; means disposed to receive the X-direction reciprically scanned modulated coherent light beam for reciprocally imparting a scan thereof in a Y-direction; means coupled to the modulating means, the X-direction scan reciprocally imparting means and the Y-direction scan reciprocally imparting means for acousto electronically controlling the modulation, the X-direction scan and the Y-direction scan, respectfully; means aligned to receive the X- and Y-direction reciprocally scanned modulated coherent light beam for selectively changing the polarization orientation of linearly polarized light incident thereon in direct response to the voltage pattern directly produced therein by X- and Y-direction reciprocally scanned modulated coherent light beam; means disposed for projecting a high intensity light beam in a light path to the light polarization orientation changing means; and means interposed in the light path between the light polarization orientation changing means and the high intensity light beam projecting means for reflecting linearly polarized high intensity light onto the light polarization orientation changing means and for directing modulated reflected high intensity light modulated in accordance with the X- and Y-direction reciprocally scanned modulated coherent light beam onto the distant screen in the form of the real-time, high-resolution images at video image signal rates.
Claim 2
Dependent Claim
266 words
An improved apparatus for displaying real-time, ultra-high resolution projected images on a distant screen in accordance with video image signal rates comprising: a laser providing a beam of coherent light; means located to receive the beam of coherent light for modulating it at video image signal rates; means disposed to receive the video rate modulated coherent light beam from the modulating means for reciprocally imparting a scan thereof in an X-direction; means disposed to receive the X-direction reciprically scanned modulated coherent light beam for reciprocally imparting a scan thereof in a Y-direction; means coupled to the modulating means, the X-direction scan reciprocally imparting means and the Y-direction scan reciprocally imparting means for acousto electronically controlling the modulation, the X-direction scan and the Y-direction scan, respectfully; means aligned to receive the X- and Y-direction reciprocally scanned modulated coherent light beam for selectively changing the polarization orientation of linearly polarized light incident thereon in direct response to the voltage pattern directly produced therein by X- and Y-direction reciprocally scanned modulated coherent light beam; means disposed for projecting a high intensity light beam in a light path to the light polarization orientation changing means; and means interposed in the light path between the light polarization orientation changing means and the high intensity light beam projecting means for reflecting linearly polarized high intensity light onto the light polarization orientation changing means and for directing modulated reflected high intensity light modulated in accordance with the X- and Y-direction reciprocally scanned modulated coherent light beam onto the distant screen in the form of the real-time, high-resolution images at video image signal rates.
Claim 3
Dependent Claim
67 words
An apparatus according to claim 1 in which the light polarization orientation changing means is a liquid crystal light valve and the modulated coherent beam is a writing beam that scans a photosensitive layer of the liquid crystal light valve and the reflected linearly polarized high intensity light is reflected through a liquid crystal layer that effects a modulation of the linearly polarized high linearity projection beam.
Claim 4
Dependent Claim
30 words
An apparatus according to claim 2 in which the modulating means is an acousto-optic diffraction modulator modulating the light intensity of the first diffraction order with the video image signals.
Claim 5
Dependent Claim
42 words
An apparatus according to claim 3 in which the X-direction scan reciprocally imparting means and the Y-direction scan reciprocally imparting means are two acousto-optic diffraction deflectors affecting the X- and Y-scans in accordance with line scan signals of the video image signals.
Claim 6
Dependent Claim
41 words
An apparatus according to claim 2 in which the X-direction scan reciprocally imparting means the Y-direction scan reciprocally imparting means are two acousto-optic diffraction deflectors affecting the X- and Y-scans in accordance with line scan signals of the video image signals.
Claim 7
Dependent Claim
22 words
An apparatus according to claim 4 in which the X and Y scan acousto-optic diffraction deflectors are TeO 2 , tellurium dioxide.
Claim 8
Dependent Claim
19 words
An apparatus according to claim 6 in which the modulating acousto-optic diffraction modulator is TeO 2 , tellurium dioxide.
Claim 9
Dependent Claim
22 words
An apparatus according to claim 7 in which the modulated reflected high intensity reflecting and directing means is a polarizing beam splitter.
Claim 10
Dependent Claim
43 words
An apparatus according to claim 8 in which the acousto-electronically controlling means is fabricated to assure scanning the modulated coherent light beam at video scan rates using two acousto-optic beam deflectors to provide a raster scanned image onto a liquid crystal light valve.
Claim 11
Dependent Claim
43 words
An apparatus according to claim 2 in which the acousto-electronically controlling means is fabricated to assure scanning the modulated coherent light beam at video scan rates using two acousto-optic beam deflectors to provide a raster scanned image onto a liquid crystal light valve.
Claim 12
Dependent Claim
275 words
An improved apparatus for displaying real-time, ultra-high resolution projected images on a distant screen in accordance with video image signal rates comprising: a laser providing a beam of coherent light; means located to receive the beam of coherent light for modulating it at video image signal rates; means disposed to receive the video rate modulated coherent light beam from the modulating means for reciprocally imparting a scan thereof in an X-direction; a galvanometer driven mirror disposed to receive the X-direction reciprically scanned modulated coherent light beam for reciprocally imparting a scan thereof in a Y-direction; means coupled to the modulating means, the X-direction scan reciprically imparting means and the Y-direction scan reciprocally imparting galvanometer driven mirror for acousto electronically controlling the modulation and the X-direction scan and for electromechanically imparting the Y-direction scan, respectfully; means aligned to receive the X- and Y-direction reciprocally scanned modulated coherent light beam for selectively changing the polarization orientation of linearly polarized light incident thereon in direct response to the voltage pattern directly produced therein by X- and Y-direction reciprocally scanned modulated coherent light beam; means disposed for projecting a high intensity light beam in a light path to the light polarization orientation changing means; and means interposed in the light path between the light polarization orientation changing means and the high intensity light beam projecting means for reflecting linearly polarized high intensity light onto the light polarization orientation changing means and for directing modulated reflected high intensity light modulated in accordance with the X- and Y-direction reciprocally scanned modulated coherent light beam onto the distant screen in the form of the real-time, high-resolution images at video image signal rates.
Claim 13
Dependent Claim
275 words
An improved apparatus for displaying real-time, ultra-high resolution projected images on a distant screen in accordance with video image signal rates comprising: a laser providing a beam of coherent light; means located to receive the beam of coherent light for modulating it at video image signal rates; means disposed to receive the video rate modulated coherent light beam from the modulating means for reciprocally imparting a scan thereof in an X-direction; a galvanometer driven mirror disposed to receive the X-direction reciprically scanned modulated coherent light beam for reciprocally imparting a scan thereof in a Y-direction; means coupled to the modulating means, the X-direction scan reciprically imparting means and the Y-direction scan reciprocally imparting galvanometer driven mirror for acousto electronically controlling the modulation and the X-direction scan and for electromechanically imparting the Y-direction scan, respectfully; means aligned to receive the X- and Y-direction reciprocally scanned modulated coherent light beam for selectively changing the polarization orientation of linearly polarized light incident thereon in direct response to the voltage pattern directly produced therein by X- and Y-direction reciprocally scanned modulated coherent light beam; means disposed for projecting a high intensity light beam in a light path to the light polarization orientation changing means; and means interposed in the light path between the light polarization orientation changing means and the high intensity light beam projecting means for reflecting linearly polarized high intensity light onto the light polarization orientation changing means and for directing modulated reflected high intensity light modulated in accordance with the X- and Y-direction reciprocally scanned modulated coherent light beam onto the distant screen in the form of the real-time, high-resolution images at video image signal rates.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-08 | 1990-03-10 | 1990-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-08 | 1994-03-10 | 1994-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-08 | 1998-03-10 | 1998-09-09 | $7700.00 | Window Closed / Lapsed |