US4610499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diffraction diffusion screen with holographically suppressed zero-order beam
Assignee: United States, AIR FOCE, Secretary of
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Filing: 1984-11-01
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Granted: 1986-09-09
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Expires: 2004-11-01
Abstract
Abstract A diffusing screen (50, 50', 50", 102) of a transmission hologram (54, 80, 94, 112) located adjacent to a diffraction optics directional diffusing screen (52, 86, 92, 114) supresses zero-order light from the diffusing screen thereby providing a device having the advantages of a directional diffusing screen but which does not have the disadvantages associated with zero-order light.
Inventors
- 👤 Mao-Jin Chern
- 👤 Ronald T. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:18
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/32
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
74 words
A zero-order suppressed directional diffusing screen for directing light from an image light source to an observation area comprising: a diffraction optics directional diffusing screen for diffracting image light from the image light source to the observation area; and a transmission hologram disposed adjacent said diffraction optics directional screen and configured to diffract only the zero-order portion of said image light transmitted by said diffraction optics directional diffusing screen away from the observation area.
Claim 2
Dependent Claim
74 words
A zero-order suppressed directional diffusing screen for directing light from an image light source to an observation area comprising: a diffraction optics directional diffusing screen for diffracting image light from the image light source to the observation area; and a transmission hologram disposed adjacent said diffraction optics directional screen and configured to diffract only the zero-order portion of said image light transmitted by said diffraction optics directional diffusing screen away from the observation area.
Claim 3
Dependent Claim
25 words
The directional diffusing screen defined in claim 1 wherein said transmission hologram is located between said diffraction optics directional diffusing screen and the observation area.
Claim 4
Dependent Claim
25 words
The directional diffusing screen defined in claim 1 wherein said diffraction optics directional diffusing screen is located between said transmission hologram and the observation area.
Claim 5
Dependent Claim
52 words
The directional diffusing screen defined in claim 2 wherein said transmission hologram is disposed in air, and further comprising a hologram-air interface configured to diffract said zero-order portion of said image light at an angle large enough to totally reflect said zero-order portion of said image light off of said hologram-air interface.
Claim 6
Dependent Claim
36 words
The directional diffusing screen defined in claim 3 wherein said diffraction optics diffusing screen includes a central axis extending essentially perpendicular to the image light source and the observation area is located along said central axis.
Claim 7
Dependent Claim
81 words
Apparatus for deflecting a beam of incident radiation comprising: a diffraction optics diffusing screen positioned to diffract a portion of the beam of incident radiation and to pass the rest of the radiation therethrough in an undiffracted manner as zero-order light; and a transmission hologram laminated to said diffraction optics diffusing screen to intercept said zero-order light and some of said portion of the beam, said hologram configured to diffract only said zero-order light and to pass all other light intercepted.
Claim 8
Dependent Claim
81 words
Apparatus for deflecting a beam of incident radiation comprising: a diffraction optics diffusing screen positioned to diffract a portion of the beam of incident radiation and to pass the rest of the radiation therethrough in an undiffracted manner as zero-order light; and a transmission hologram laminated to said diffraction optics diffusing screen to intercept said zero-order light and some of said portion of the beam, said hologram configured to diffract only said zero-order light and to pass all other light intercepted.
Claim 9
Dependent Claim
95 words
An optical system comprising: a source of image light; an observation area; diffraction means for diffracting a predetermined substantial portion of the image light from said source of image light to said observation area whereby said predetermined substantial portion of the image light is redirected and diffused into a predetermined directional range to said observation area with preselected intensity distribution and substantially uniform illumination across said observation area; and a transmission hologram disposed between said diffraction means and said observation area, said transmission hologram configured to diffract only zero-order light transmitted by said diffraction means.
Claim 10
Dependent Claim
95 words
An optical system comprising: a source of image light; an observation area; diffraction means for diffracting a predetermined substantial portion of the image light from said source of image light to said observation area whereby said predetermined substantial portion of the image light is redirected and diffused into a predetermined directional range to said observation area with preselected intensity distribution and substantially uniform illumination across said observation area; and a transmission hologram disposed between said diffraction means and said observation area, said transmission hologram configured to diffract only zero-order light transmitted by said diffraction means.
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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 |