LCD-based confidential viewing apparatus utilizing auto-inversion masking
First Claim
1. A display apparatus for displaying an image only to an intended viewer, comprising:
- a. a display device configured for displaying an image, said display device including a first polarizer, a second polarizer, and an optical rotator disposed between said first and second polarizer, wherein at least said second polarizer constitutes a variable polarizer;
b. said second variable polarizer being configured to alternate between differing states of polarization so as to cause said image to be multiplexed with an inverted image thereof on said display to produce a combined obscured image;
c. an image decoder synchronized with said display device for extraction of said image from said obscured image for viewing only by the intended viewer.
3 Assignments
0 Petitions
Accused Products
Abstract
A display apparatus having a pair of polarizers with an optical rotator therebetween, one of the polarizers being a variable polarizer which is independently operated to alternate between substantially orthogonal states of polarization and cause the display to rapidly alternate between a normal positive and inverted negative image, creating a combined neutral image that in indecipherable to the naked eye. Shutter eyewear synchronized with the variable polarizer is used to extract the positive image for viewing by an intended viewer. In another embodiment, both polarizers of the display apparatus are independently variable, which allows for viewing of the desired image using passive polarized eyewear or eyewear incorporating synchronized variable polarizing rotators. Faster independent operation of the variable polarizers provide for flicker-free viewing of the desired image and convenient switching between normal and secure modes of operation, without physical alteration of the display.
-
Citations
24 Claims
-
1. A display apparatus for displaying an image only to an intended viewer, comprising:
-
a. a display device configured for displaying an image, said display device including a first polarizer, a second polarizer, and an optical rotator disposed between said first and second polarizer, wherein at least said second polarizer constitutes a variable polarizer; b. said second variable polarizer being configured to alternate between differing states of polarization so as to cause said image to be multiplexed with an inverted image thereof on said display to produce a combined obscured image; c. an image decoder synchronized with said display device for extraction of said image from said obscured image for viewing only by the intended viewer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A display apparatus for displaying an image only to an intended viewer, comprising:
-
a. an display device having first and second polarizing light filters between which first and second optical rotators are disposed, said display device being configured to display an image thereon; b. said second optical rotator being configured to alternate the orientation of light passing therethrough between substantially orthogonal positions, thereby producing a combined substantially featureless image on said display which is composed of components of said image and an inverted image thereof; c. an image decoder synchronized with said display device to extract said image to be viewed from said substantially featureless image for viewing only by the intended viewer. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
Specification