US5612708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color helmet mountable display
Assignee: Raytheon Co
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Filing: 1996-04-22
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Granted: 1997-03-18
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Expires: 2016-04-22
Abstract
Abstract A lighter weight helmet mountable display (HMD) that is easily adjustable to accommodate variable inter-pupillary distances includes substantially parallel left and right optical channels, and projects left and right images onto the helmet's visor. Each channel includes light sources that form a complete scan line of the image, and project luminance patterns for successive scan lines through a lens which reduces the light's divergence. A deflector is moved to deflect successive luminance patterns back through the lens so that the lens focuses the patterns onto successive scan lines on a back projection screen. The screen emits luminance patterns in response to the incident luminance patterns for each successive scan line to project the image onto the visor.
Inventors
- 👤 David A. Ansley
- 👤 William S. Beamon, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:36
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/01; G02B27/017; G02B27/0172; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3129; H04N9/3132; H04N9/3138; G02B27/0101; G02B2027/0112; G02B2027/0132; G02B2027/014; G02B27/0149; G02B2027/0154; G02B7/00; G02B7/02; G02B7/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
183 words
A helmet mountable display system for displaying left and right pixelated images onto a visor for viewing by a wearer of the helmet, said display system comprising: left and right optical channels having respective central optical axes that are substantially parallel to each other, each channel comprising: an array of light sources forming a complete scan line of said image in one-to-one correspondence with the image pixels, said light sources projecting first divergent luminance patterns for successive scan lines; a lens for reducing the divergence of said first luminance patterns; a back projection screen positioned to project said images onto the visor; a scanning deflector; and a deflector actuator controlling said scanning deflector to deflect successive first luminance patterns transmitted through the lens back through said lens so that the lens focuses the patterns onto successive scan lines on the screen's back side, said screen emitting a second luminance pattern for each successive scan line to project the pixelated image onto the visor, said deflector actuators in said left and right optical channels comprising a single common drive motor for controlling both deflectors.
Claim 2
Dependent Claim
183 words
A helmet mountable display system for displaying left and right pixelated images onto a visor for viewing by a wearer of the helmet, said display system comprising: left and right optical channels having respective central optical axes that are substantially parallel to each other, each channel comprising: an array of light sources forming a complete scan line of said image in one-to-one correspondence with the image pixels, said light sources projecting first divergent luminance patterns for successive scan lines; a lens for reducing the divergence of said first luminance patterns; a back projection screen positioned to project said images onto the visor; a scanning deflector; and a deflector actuator controlling said scanning deflector to deflect successive first luminance patterns transmitted through the lens back through said lens so that the lens focuses the patterns onto successive scan lines on the screen's back side, said screen emitting a second luminance pattern for each successive scan line to project the pixelated image onto the visor, said deflector actuators in said left and right optical channels comprising a single common drive motor for controlling both deflectors.
Claim 3
Dependent Claim
43 words
The helmet mountable display system of claim 1, further comprising an adjustment mechanism for adjusting the separation distance between said parallel channels without moving said deflectors and deflector actuators so that the distance can be set substantially equal to a wearer's interpupillary distance.
Claim 4
Dependent Claim
44 words
The helmet mountable display system of claim 1, wherein said lens and said deflector capture an angle of the diverging light, the size of the deflector being selected to capture the minimum angle of light needed to resolve the individual sources at the screen.
Claim 5
Dependent Claim
51 words
The helmet mountable display system of claim 3, wherein the light projected at said minimum angle along the focal length of said lens provides a first illumination area, and said back projection screen projects said second luminance patterns at another angle to provide a second illumination area larger than the first.
Claim 6
Dependent Claim
20 words
The helmet mountable display system of claim 1, wherein said lens collimates the divergent luminance pattern from said light sources.
Claim 7
Dependent Claim
33 words
The helmet mountable display system of claim 5, wherein said lens comprises a plurality of lens elements for collimating said divergent luminance patterns, and for focusing said deflected luminance patterns onto said screen.
Claim 8
Dependent Claim
17 words
The helmet mountable display system of claim 1, wherein said light sources are light emitting diodes (LEDs).
Claim 9
Dependent Claim
32 words
The helmet mountable display system of claim 1, further comprising: a circuit for reading out successive scan lines from said images, and modulating said light sources to project the first luminance patterns.
Claim 10
Dependent Claim
34 words
The helmet mountable display system of claim 8, wherein said circuit modulates said light sources at a scanning rate, and said deflector actuator moves said deflector at a rate synchronized to said scanning rate.
Claim 11
Dependent Claim
36 words
The helmet mountable display system of claim 9, wherein said deflector is a multi-faceted mirror, and said deflector actuator rotates said mirror such that the facets of said mirror deflect respective successive images onto said screen.
Claim 12
Dependent Claim
26 words
The helmet mountable display system of claim 8, wherein said circuit reads out said image in a raster scan format, and modulates said light sources sequentially.
Claim 13
Dependent Claim
28 words
The helmet mountable display system of claim 8, wherein said circuit reads out said image a complete scan line at a time, and modulates the light sources simultaneously.
Claim 14
Dependent Claim
51 words
The helmet mountable display system of claim 8, wherein said array comprises multiple linear adjacent arrays with mutually staggered light sources, said circuit temporally staggering the modulation of the light sources among said arrays such that luminance patterns are deflected from each array onto the same scan line on the screen.
Claim 15
Dependent Claim
79 words
The helmet mountable display system of claim 8, wherein said images are color images with red, green and blue (RGB) components, and said light sources include red, green, and blue light source arrays each in one-to-one correspondence with the scan line, said circuit delaying the modulation of the three arrays such that the luminance patterns for the three arrays are coincident on the same projected scan line, and said back projection screen projecting color luminance patterns onto the visor.
Claim 16
Dependent Claim
16 words
The helmet mountable display system of claim 1, wherein said array of light sources is linear.
Claim 17
Dependent Claim
85 words
A helmet mountable display (HMD), comprising: parallel left and right optical channels for projecting left and right images scan lines; left and right scanning deflectors; a common drive motor for controlling said scanning deflectors to deflect successive image scan lines back through the optical channels to project an image onto a visor; and an adjustment mechanism that adjust the spacing between the channels without moving the left and right scanning deflectors to accommodate varying inter-pupillary distances while maintaining the channels parallel orientation to prevent distortion.
Claim 18
Dependent Claim
85 words
A helmet mountable display (HMD), comprising: parallel left and right optical channels for projecting left and right images scan lines; left and right scanning deflectors; a common drive motor for controlling said scanning deflectors to deflect successive image scan lines back through the optical channels to project an image onto a visor; and an adjustment mechanism that adjust the spacing between the channels without moving the left and right scanning deflectors to accommodate varying inter-pupillary distances while maintaining the channels parallel orientation to prevent distortion.
Claim 19
Dependent Claim
43 words
The HMD of claim 16, wherein said image has a plurality of pixels in each scan line, each optical channel including light sources in one-to-one correspondence with the pixels in each scan line for projecting the image scan lines onto said scanning deflector.
Claim 20
Dependent Claim
27 words
The HMD of claim 17, wherein the HMD includes only one pair of scanning deflectors, and said pair of scanning deflectors share only one common drive motor.
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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) | 2000-03-17 | 2000-09-16 | 2001-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-17 | 2004-09-16 | 2005-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-17 | 2008-09-16 | 2009-03-18 | $7700.00 | Window Closed / Lapsed |