US4688879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Holographic multi-combiner for head-up display
Assignee: Kaiser Optical Systems Inc
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Filing: 1985-07-08
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Granted: 1987-08-25
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Expires: 2005-07-08
Abstract
Abstract A head-up display which combines an internal image, produced by a cathode ray tube image source, at substantially a wavelength of light λ, with an external image, using a holographic optical element. The holographic optical element consists of two or more holographic optical subelements in series, each satisfying the Bragg condition with respect to wavefronts at the wavelength λ from a particular direction. While wavefronts satisfying these conditions are reflected to the observer's field of view, all others are transmitted through the holographic subelements. The holographic optical subelements largely overlap in the direction of their illumination by the internal image source, and may slightly overlap in the direction their images are to be presented to the observer. Wavelength λ is chosen at the peak of the phosphor response curve of the cathode ray tube image source.
Inventors
- 👤 Ronald C. Fairchild
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:40
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/1086; G02B27/1093; G02B27/01; G02B27/0101; G02B27/0103; G02B2027/0112; G02B2027/0116; G02B2027/0118; G02B5/00; G02B5/32
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
179 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the source output to the pilot and consisting of a plurality of HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the source and the pilot so that a portion of the light reaching one of the subelements from the source intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching said one subelement intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects another of the subelements at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from more than one subelement.
Claim 2
Dependent Claim
179 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the source output to the pilot and consisting of a plurality of HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the source and the pilot so that a portion of the light reaching one of the subelements from the source intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching said one subelement intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects another of the subelements at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from more than one subelement.
Claim 3
Dependent Claim
12 words
The head-up display of claim 1, wherein said combiner subelements are planar.
Claim 4
Dependent Claim
16 words
The head-up display of claim 1, wherein the display information source is a cathode ray tube.
Claim 5
Dependent Claim
191 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength, lens means for collimating the light from the source, and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the collimated source output to the pilot and consisting of a plurality of HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the lens means and the pilot so that a portion of the light reaching one of the subelements from the lens means intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching said one subelement intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects another of the subelements at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from more than one subelement.
Claim 6
Dependent Claim
191 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength, lens means for collimating the light from the source, and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the collimated source output to the pilot and consisting of a plurality of HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the lens means and the pilot so that a portion of the light reaching one of the subelements from the lens means intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching said one subelement intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects another of the subelements at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from more than one subelement.
Claim 7
Dependent Claim
12 words
The head-up display of claim 4, wherein said combiner subelements are planar.
Claim 8
Dependent Claim
13 words
The head-up display of claim 5, wherein said combiner subelements are mutually parallel.
Claim 9
Dependent Claim
16 words
The head-up display of claim 4, wherein the display information source is a cathode ray tube.
Claim 10
Dependent Claim
195 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength, reflecting means for reflecting the light output, lens means for collimating ther reflected light, and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the collimated light to the pilot and consisting of two parallel planar HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the lens means and the pilot so that a portion of the light reaching the subelement closer to the lens means intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching the subelement closer to the lens means intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects the other subelement at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from two subelements.
Claim 11
Dependent Claim
195 words
A head-up display supported in an aircraft cockpit having a windshield, including a display information source having a light output at a predetermined wavelength, reflecting means for reflecting the light output, lens means for collimating ther reflected light, and a combiner supported in the pilot's field of view through the cockpit windshield, the combiner being operative to reflect the collimated light to the pilot and consisting of two parallel planar HOE combiner subelements each constructed to reflect the predetermined wavelength, supported relative to the lens means and the pilot so that a portion of the light reaching the subelement closer to the lens means intersects the subelement at substantially the Bragg angle and is reflected to the pilot's eye and another portion of the light reaching the subelement closer to the lens means intersects the subelement at an angle substantially different from the Bragg angle and is transmitted through said subelement and at least part of such transmitted light intersects the other subelement at substantially the Bragg angle and is reflected from such other subelement to the pilot's eye, whereby the pilot perceives an image of the source formed by light reflected from two subelements.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |