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US5717422A Expired / Lapsed US ⏱️ 0.0 years remaining

Variable intensity high contrast passive display

Assignee: Fergason Patent Properties LLC
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Filing: 1995-11-16
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Granted: 1998-02-10
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Expires: 2015-11-16
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Abstract

Abstract A display includes a light modulator, a source of light, and a control for controlling the intensity of light from the source supplied to the light modulator thereby to provide images of good contrast for both bright and dark scenes. A method of displaying an image using a passive light modulating display apparatus includes controlling the intensity of light illuminating the display apparatus as a function of a brightness characteristic of the image.

Inventors

  • 👤 James L. Fergason

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 10:36
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3141; H04N9/315; H04N9/3155; G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/3406; H04N9/317; G09G2310/00; G09G2310/02; G09G2310/0235; G09G2320/00; G09G2320/06; G09G2320/0626; G09G2360/00; G09G2360/14; G09G2360/144; G09G2360/16; G09G3/2007

Claims Analysis

Total Claims: 27
Claim 1
Independent Claim 145 words
Apparatus for displaying an optical image represented by input signals indicating contrast and brightness information of the optical image, comprising a passive light modulating display to modulate light in response to the input signals representing contrast characteristics of the optical image to display the optical image, light supply means for supplying a light input to said display for modulation by said display to produce the optical image output, and control means responsive to the input signals for controlling the intensity of light supplied by said light supply means based on such brightness information, said control means comprising means for controlling, as a function of a desired optical output of the passive light modulating display, the intensity of light provided to the passive light modulating display by the light supply means to alter the brightness of the optical image output substantially without affecting the contrast ratio.
Claim 2
Dependent Claim 145 words
Apparatus for displaying an optical image represented by input signals indicating contrast and brightness information of the optical image, comprising a passive light modulating display to modulate light in response to the input signals representing contrast characteristics of the optical image to display the optical image, light supply means for supplying a light input to said display for modulation by said display to produce the optical image output, and control means responsive to the input signals for controlling the intensity of light supplied by said light supply means based on such brightness information, said control means comprising means for controlling, as a function of a desired optical output of the passive light modulating display, the intensity of light provided to the passive light modulating display by the light supply means to alter the brightness of the optical image output substantially without affecting the contrast ratio.
Claim 3
Dependent Claim 57 words
The apparatus of claim 1, said control means comprising means for computing the brightness information from the input signals representing at least a portion of an image to be produced by the apparatus and for controlling intensity of light supplied by said light supply means to the passive light modulating display as a function of such computing.
Claim 4
Dependent Claim 12 words
The apparatus of claim 2, said means for computing comprising a computer.
Claim 5
Dependent Claim 43 words
The apparatus of claim 2, said control means comprising means for computing from the input signals the average brightness of the entire scene containing the optical image for display by the apparatus and for controlling intensity as a function of such average brightness.
Claim 6
Dependent Claim 24 words
The apparatus of claim 1 further comprising means for detecting ambient brightness in the local environment where such image output is to be displayed.
Claim 7
Dependent Claim 36 words
The apparatus of claim 5, said control means comprising means responsive to said means for detecting for controlling intensity of light supplied to the passive light modulating display also as a function of the ambient brightness.
Claim 8
Dependent Claim 21 words
The apparatus of claim 1, the control means comprising means for controlling the passive light modulating display to produce respective images.
Claim 9
Dependent Claim 32 words
The apparatus of claim 7, said light supply means comprising a plurality of light sources, and the control means comprising means for controlling the intensity of a plurality of said light sources.
Claim 10
Dependent Claim 41 words
The apparatus of claim 8, the control means comprising means for controlling the passive light modulating display to produce frame sequential images and means for controlling respective light sources as a function of which image is produced at a particular time.
Claim 11
Dependent Claim 50 words
The apparatus of claim 1, further comprising a plurality of light sources of different respective colors, and said control means comprising means for operating said passive light modulating display in a field sequential mode while controlling the brightness of light emitted from respective light sources, whereby multicolor images are developed.
Claim 12
Dependent Claim 15 words
The apparatus of claim 1, said passive light modulating display comprising a liquid crystal display.
Claim 13
Dependent Claim 16 words
The apparatus of claim 11, said liquid crystal display comprising a variable birefringence liquid crystal apparatus.
Claim 14
Dependent Claim 15 words
The apparatus of claim 11, said liquid crystal display comprising a reflective liquid crystal device.
Claim 15
Dependent Claim 25 words
The apparatus of claim 1, said control means comprising means to control intensity while operating the passive light modulating display in a field sequential mode.
Claim 16
Independent Claim 116 words
A method of displaying an image represented by input signals indicating contrast and brightness information of the image, comprising directing light from a light source to a passive light modulating display apparatus, supplying the input signals to the display apparatus representing characteristics of the image to form the image for display, and controlling the intensity of light illuminating the display apparatus from the light source as a function of such brightness information, said controlling comprising controlling, as a function of a desired optical output of the passive light modulating display apparatus, the intensity of light provided to the passive light modulating display apparatus to alter the brightness of the image substantially without affecting the contrast ratio.
Claim 17
Independent Claim 116 words
A method of displaying an image represented by input signals indicating contrast and brightness information of the image, comprising directing light from a light source to a passive light modulating display apparatus, supplying the input signals to the display apparatus representing characteristics of the image to form the image for display, and controlling the intensity of light illuminating the display apparatus from the light source as a function of such brightness information, said controlling comprising controlling, as a function of a desired optical output of the passive light modulating display apparatus, the intensity of light provided to the passive light modulating display apparatus to alter the brightness of the image substantially without affecting the contrast ratio.
Claim 18
Dependent Claim 29 words
The method of claim 15; said controlling comprising using a computer to compute the average brightness of the image and controlling intensity of light based on such average brightness.
Claim 19
Dependent Claim 36 words
The method of claim 15, comprising producing respective images using the display apparatus in a field sequential mode, and said controlling comprising as each image is produced controlling intensity of the light illuminating the display apparatus.
Claim 20
Dependent Claim 40 words
The method of claim 15; comprising producing respective images using the display apparatus in a field sequential mode, and as each image is produced controlling intensity of different respective colors of light from the light source illuminating the display apparatus.
Claim 21
Dependent Claim 69 words
The method of claim 15, said directing comprising supplying light from a source to the passive light modulating display apparatus, and further comprising using such display to modulate light to produce an output image, and said controlling comprising controlling intensity of light supplied to the passive light modulating display apparatus as a function of desired brightness of the output image substantially without changing contrast ratio of the output image.
Claim 22
Dependent Claim 65 words
The method of claim 15, said directing comprising supplying light from a source to the passive light modulating display apparatus, and further comprising using such passive light modulating display apparatus to modulate such light to produce an output image, and said controlling comprising controlling intensity of light supplied to the passive light modulating display apparatus as a function of desired brightness of the output image.
Claim 23
Dependent Claim 37 words
The method of claim 15, said controlling comprising computing from the input signals the brightness information of a particular image or scene and in response to such computation controlling the intensity or brightness of the output light.
Claim 24
Dependent Claim 33 words
The method of claim 15, said directing comprising supplying light from a light source to a display, and said controlling of intensity or brightness comprising controlling intensity or brightness of the light source.
Claim 25
Dependent Claim 40 words
The method of claim 22, wherein an output image is produced by plural pixels included in the passive light modulating display apparatus, and said controlling comprises modulating light without having to reduce the number of pixels used to transmit light.
Claim 26
Dependent Claim 84 words
The method of claim 15, said directing comprising supplying light from a light source to the passive light modulating display apparatus, and wherein an output image is produced by modulating light by plural pixels included in the passive light modulating display apparatus, and said controlling comprises controlling intensity of the light illuminating the passive light modulating display apparatus while a full number or a relatively large number of pixels form an image or scene even if the brightness of the scene is relatively dark.
Claim 27
Dependent Claim 34 words
The method of claim 15, said controlling comprising integrating the input signals to determine brightness of light from the light source incident on the passive light modulating display apparatus to form an image output.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-02-09 2001-08-11 2002-02-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-02-09 2005-08-11 2006-02-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-02-09 2009-08-11 2010-02-10 $7700.00 Window Closed / Lapsed

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