Patent US5272473A successfully refreshed from Google Patents.
US5272473A
Expired / Lapsed
US
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Reduced-speckle display system
Assignee: Texas Instruments Inc
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Filing: 1992-08-17
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Granted: 1993-12-21
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Expires: 2012-08-17
Abstract
Abstract A digitized video system with an increased viewing angle having a light projector and a display screen. The light projector generating a plurality of narrow light beams to impinge on the display screen at a plurality of associated points. The display screen has a transducer generating surface acoustic waves which traverse the associated points. This results in reduced laser speckle.
Inventors
- 👤 E. Earle Thompson
- 👤 Thomas W. DeMond
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:21
CPC Classifications
G; G09; G09F; G09F19/00; G09F19/12; G09F19/18; G02; G02B; G02B27/00; G02B27/48
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
57 words
A coherent light projection system having reduced speckle comprising: a coherent light source; a display screen; said coherent light source for generating a light beam to impinge on said display screen at a point; and said display screen having a transducer coupled thereto operative to generate surface acoustic waves wherein said surface acoustic waves traverse said point.
Claim 2
Dependent Claim
57 words
A coherent light projection system having reduced speckle comprising: a coherent light source; a display screen; said coherent light source for generating a light beam to impinge on said display screen at a point; and said display screen having a transducer coupled thereto operative to generate surface acoustic waves wherein said surface acoustic waves traverse said point.
Claim 3
Dependent Claim
17 words
The projection system as claimed in claim 1 wherein said surface acoustic waves have an ultrasonic frequency.
Claim 4
Dependent Claim
18 words
The projection system as claimed in claim 1 wherein said display screen is of a back projection configuration.
Claim 5
Dependent Claim
16 words
The projection system as claimed in claim 1 wherein said coherent light source is a laser.
Claim 6
Dependent Claim
24 words
The projection system as claimed in claim 1 wherein said surface acoustic waves have an amplitude greater than one wavelength of said light beam.
Claim 7
Dependent Claim
30 words
The projection system as claimed in claim 1 wherein said display system further comprises a spatial light modulator operative to direct said light beam to impinge on said display screen.
Claim 8
Dependent Claim
16 words
The projection system as claimed in claim 1 wherein said surface acoustic waves are substantially parallel.
Claim 9
Independent Claim
62 words
A method of reducing speckle in a coherent light source projection system having a display screen comprising: generating a surface acoustic wave that traverses said display screen; generating a coherent light beam; directing said coherent light beam toward said display screen; and said coherent light beam impinging said display screen at a point where said surface acoustic wave traverses said display screen.
Claim 10
Independent Claim
62 words
A method of reducing speckle in a coherent light source projection system having a display screen comprising: generating a surface acoustic wave that traverses said display screen; generating a coherent light beam; directing said coherent light beam toward said display screen; and said coherent light beam impinging said display screen at a point where said surface acoustic wave traverses said display screen.
Claim 11
Dependent Claim
17 words
The method as claimed in claim 8 wherein said light beam substantially passes through said display screen.
Claim 12
Dependent Claim
24 words
The method as claimed in claim 8 wherein said directing step is performed by modulating at least one element of a spatial light modulator.
Claim 13
Dependent Claim
84 words
A coherent light projection system having reduced speckle comprising: a coherent light source; said coherent light source for generating a first light beam; a spatial light separator for dividing said first light beam into a plurality of second light beams, wherein said separator comprises an array of separately controlled, discrete elements; a display screen for receiving predetermined ones of said second light beams; and selected ones of said predetermined ones of said second light beams have different phases when received by said display screen.
Claim 14
Dependent Claim
84 words
A coherent light projection system having reduced speckle comprising: a coherent light source; said coherent light source for generating a first light beam; a spatial light separator for dividing said first light beam into a plurality of second light beams, wherein said separator comprises an array of separately controlled, discrete elements; a display screen for receiving predetermined ones of said second light beams; and selected ones of said predetermined ones of said second light beams have different phases when received by said display screen.
Claim 15
Dependent Claim
18 words
The projection system as claimed in claim 11 wherein said display screen is of a back projection configuration.
Claim 16
Dependent Claim
16 words
The projection system as claimed in claim 11 wherein said coherent light source is a laser.
Claim 17
Dependent Claim
18 words
The projection system as claimed in claim 11 wherein said spatial light separator is a spatial light modulator.
Claim 18
Dependent Claim
33 words
The projection system as claimed in claim 11 wherein said different phases of said selected ones of said predetermined ones of said second light beams are the result of differing optical path lengths.
Claim 19
Dependent Claim
31 words
The projection system as claimed in claim 11 wherein said said selected ones of said predetermined ones of said second light beams have differing optical path lengths to said display screen.
Claim 20
Independent Claim
85 words
A method for reducing speckle in a coherent light projection system comprising: generating a first coherent light beam; dividing said first coherent light beam into a plurality of second coherent light beams, with the use of a spatial light separator comprising an array of individually controlled discrete elements; and directing predetermined ones of said second coherent light beams toward a display screen wherein selected ones of said predetermined ones of said second coherent light beams are in differing phase when they impinge said display screen.
Claim 21
Independent Claim
85 words
A method for reducing speckle in a coherent light projection system comprising: generating a first coherent light beam; dividing said first coherent light beam into a plurality of second coherent light beams, with the use of a spatial light separator comprising an array of individually controlled discrete elements; and directing predetermined ones of said second coherent light beams toward a display screen wherein selected ones of said predetermined ones of said second coherent light beams are in differing phase when they impinge said display screen.
Claim 22
Dependent Claim
18 words
The method as claimed in claim 17 wherein said predetermined light beams substantially pass through said display screen.
Claim 23
Dependent Claim
24 words
The method as claimed in claim 17 including the step of varying the optical path length of different ones of said coherent light beams.
Claim 24
Dependent Claim
24 words
The method as claimed in claim 17 wherein said dividing step and said directing step are substantially simultaneously performed by said spatial light separator.
Claim 25
Dependent Claim
61 words
A projection system having increased viewing angle comprising: a light projector; a display screen; said light projector for generating a plurality of narrow light beams to impinge on said display screen at a plurality of associated points; and said display screen having a transducer coupled thereto operative to generate surface acoustic waves wherein said surface acoustic waves traverse said associated points.
Claim 26
Dependent Claim
61 words
A projection system having increased viewing angle comprising: a light projector; a display screen; said light projector for generating a plurality of narrow light beams to impinge on said display screen at a plurality of associated points; and said display screen having a transducer coupled thereto operative to generate surface acoustic waves wherein said surface acoustic waves traverse said associated points.
Claim 27
Dependent Claim
17 words
The projection system as claimed in claim 21 wherein said surface acoustic waves have an ultrasonic frequency.
Claim 28
Dependent Claim
18 words
The projection system as claimed in claim 21 wherein said display screen is of a back projection configuration.
Claim 29
Dependent Claim
17 words
The projection system as claimed in claim 21 wherein said light projector includes a laser light source.
Claim 30
Dependent Claim
25 words
The projection system as claimed in claim 21 wherein said surface acoustic waves have an amplitude greater than one wavelength of the longest visible light.
Claim 31
Dependent Claim
29 words
The projection system as claimed in claim 21 wherein said light projector includes a spatial light modulator operative to direct said light beams to impinge on said display screen.
Claim 32
Dependent Claim
59 words
The projection system as claimed in claim 26 wherein said spatial modulator includes: an array of individual display cells; at least two memory cells associated with each display cell; a first decoder for addressing a plurality of memory cells for storing information therein; and a second decoder for addressing substantially all of said display cells to display an image.
Claim 33
Dependent Claim
16 words
The projection system as claimed in claim 21 wherein said surface acoustic waves are substantially parallel.
Claim 34
Independent Claim
61 words
A method of varying the dispersion of light from a surface comprising the steps of: generating surface acoustic waves to traverse a surface; generating a beam of light; and impinging said beam on said surface for a time period at least sufficient to allow one of said surface acoustic waves to traverse the area of said surface impinged by said beam.
Claim 35
Independent Claim
61 words
A method of varying the dispersion of light from a surface comprising the steps of: generating surface acoustic waves to traverse a surface; generating a beam of light; and impinging said beam on said surface for a time period at least sufficient to allow one of said surface acoustic waves to traverse the area of said surface impinged by said beam.
Claim 36
Dependent Claim
32 words
The method as claimed in claim 29 including the step of reflecting portions of said beam at varying angles in response to said one of said surface acoustic waves traversing said area.
Claim 37
Dependent Claim
32 words
The method as claimed in claim 29 including the step of diffracting portions of said beam at varying angles in response to said one of said surface acoustic waves traversing said area.
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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) | 1996-12-20 | 1997-06-21 | 1997-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-20 | 2001-06-21 | 2001-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-20 | 2005-06-21 | 2005-12-21 | $7700.00 | Window Closed / Lapsed |