Lighting-independent color video display

• US 5,638,084 A
• Filed: 07/29/1996
• Issued: 06/10/1997
• Est. Priority Date: 05/22/1992
• Status: Expired due to Term

• Current Assignee: NEW Visual Media Group LLC
• Original Assignee: Dielectric Systems International, Inc.
• Inventors: Kalt, Charles G.
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Lao, Lun-Yi
• Application Number:
  US08/681,606
• Time in Patent Office: 316 Days
• Field of Search: 345/84, 345/85, 345/108, 345/206, 345/88, 345/31, 345/48, 359/230, 359/223, 359/231, 359/291, 313/459, 361/280, 361/281
• US Class Current: 345/31
• CPC Class Codes: G09F 13/0472 Traffic signs
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: H04N 9/30 using solid-state colour display devices

Abstract

An electrostatically actuated color video display is disclosed which can be illuminated by backlighting transmitted through the display and by reflected ambient light to have good visibility in both bright daylight and in subdued or dim light. To display full-color dynamically changing images from an electronic video signal the functions of creating the image and of generating color light rays for use in the image are separated. A preferred embodiment employs a pixellated color screen having rectangular cells of alternate red, green, blue and a somewhat opaque white color and a shuttering mask comprising an array of selectively actuatable light-modulating capacitors with black movable electrodes that when retracted are in registration with and present an open light path to individual color screen cells and when extended present a continuous black screen appearance.

Claims

1. A flat panel video display viewable by either transmitted or reflected light, depending upon an ambient illumination level, having a layered matrix structure and employing light-modulating capacitor pixels, said layered matrix structure comprising:

i) a movable electrode shutter layer having a composite array of movable electrodes disposed toward a viewer, said movable electrodes having an open, retracted position providing a clear light path past said movable electrode and a second, extended position in which said light path is occluded by said movable electrode;

ii) a dielectric layer having a transparent sheet-like dielectric member in capacitive contact with said movable electrodes in said extended position of said movable electrodes;

iii) a control electrode layer having an array of translucent control electrodes contacting and in electrostatic engagement with a second surface of said dielectric member to control said movable electrodes, said dielectric member and said control electrodes providing an array of light-modulating capacitors;

iv) drive circuitry to apply drive voltages selectively between said fixed electrodes and said movable electrodes to effect movement of selected movable electrodes; and

v) a color screen layer disposed adjacent to said shutter layer and behind said shutter layer with respect to said viewer said color screen layer being composed of colored screen segments and being capable of displaying a similar colorant-modulated appearance by either transmitted or reflected light depending upon the ambient illumination level;

whereby movement of an individual movable electrode into a retracted, open position displays a segment of such colored screens to a viewer, multiple said movable electrodes can be actuated to display a composed image area of said colored screen segments to said viewer and whereby said composed image area is viewable by reflected light or transmitted light depending on the illumination level.

2. A flat panel video display according to claim 1, wherein each said movable electrode comprises a plastic lamina prestressed into a coiled configuration.

3. A flat panel video display according to claim 1, wherein each said movable electrode has a conductive electrode surface to contact said dielectric member.

4. A flat panel multicolor video display according to claim 3 wherein adjacent colored segments have different primary color appearances and are aligned with said movable electrodes whereby adjacent electrodes can be operated to present said different primary color appearances of said colored segments in a selective manner.

5. A flat panel video display according to claim 4 wherein said cells are arranged in adjacent groups of four cells having the appearance of three primary colors and white.

6. A flat panel video display according to claim 4 wherein said colored screen is composed of multiple layers of red, green or blue colorant-loaded transparent material arranged in patterns to give said individual cells desired visual characteristics.

7. A flat panel video display according to claim 4 wherein said cells and said movable electrodes have corresponding and similar geometrical sizes and shapes and said colored cells are arranged in repeating groups of four, each said group of four cells comprising a red cell, a green cell, a blue cell and a white cell.

8. A flat panel video display according to claim 1 wherein said movable electrodes are electrically connected in rows and said fixed control electrodes are electrically connected in columns and wherein said drive circuitry includes row-and-column diode decoding means to provide selective actuation of groups of individual movable electrodes.

9. A flat panel multi-color video display according to claim 1 comprising polychromatic colored screen segments wherein said movable electrodes present a black appearance to said viewer in said extended position and are configured and disposed for said composite array of movable electrodes to provide the appearance of a substantially continuous black screen at an intended viewing distance when said electrodes are all in said extended positions.

10. A multicolor video display for viewing by reflected light, having a layered structure and employing light-modulating capacitor pixels, said layered structure comprising:

i) a movable electrode shutter layer having a composite array of movable electrodes disposed toward a viewer, said movable electrodes having an open, retracted position defining a pixel aperture and providing a dear light path past said movable electrode and a second, extended position in which said light path is occluded by said movable electrode;

ii) a dielectric layer having a transparent dielectric member in capacitive contact with said movable electrodes in said extended position of said movable electrodes;

iii) a control electrode layer having an array of translucent control electrodes contacting and in electrostatic engagement with a second surface of said dielectric member to control said movable electrodes, said movable electrodes, said dielectric member and said control electrodes providing an array of light-modulating capacitors;

iv) a reflective, static color screen layer disposed behind the shutter layer with respect to the viewer, said color screen layer being fixedly composed of colored segments, each said colored segment corresponding with and being aligned with said one of said pixel apertures to intercept said pixel aperture light path, adjacent said segments having different colors to provide multicolor display capabilities;

whereby said color screen layer can be selectively masked by actuation of said movable electrode shutter layer to permit reflection to the viewer of an image composed of selected color screen segments.

11. A multicolor video display according to claim 10 wherein said different colors comprise three primary colors and white.

12. A multicolor video display according to claim 10 wherein said color screen segments are light-transmissive and comprising a source of illumination behind said color screen with respect to a viewer to provide a display viewable by both reflected and transmitted light.

13. A reflective, thin-panel, multicolor video display having a layered structure and employing light-modulating capacitive pixels, said layered structure comprising:

I) a movable electrode shutter layer formed from a continuous film of flexible material and having a composite array of movable electrodes, said movable electrodes each having;

a) a pigmentable reflective surface disposable toward the viewer;

b) an open, retracted position providing a clear light path past the movable electrode; and

c) a second, extended position in which said light path is occluded by the movable electrode and the movable electrode'"'"'s reflective surface is disposed toward the viewer;

ii) a dielectric layer formed from a continuous film of dielectric material and comprising a transparent, sheet-like dielectric member in capacitive contact with the movable electrodes in said extended position of each said movable electrode;

iii) a light-transmissive control electrode layer disposed in electrostatic engagement with a second surface of said dielectric member to control said movable electrodes;

wherein said movable electrodes, said dielectric member and said control electrodes provide an array of light-modulating capacitors;

iv) drive circuitry to apply drive voltages selectively between said fixed electrodes and said movable electrodes to effect movement of selected movable electrodes; and

v) a reflective color screen layer disposed adjacent to said shutter layer and behind said shutter layer with respect to said viewer, said color screen layer being composed of a mosaic of reflective colored screen segments individually configured and dimensioned to correspond with said capacitive pixels, adjacent said segments having different colors to provide multi-color display capabilities;

whereby multicolored images can be selectively displayed by electronic manipulation of said movable electrodes.

14. A video display according to claim 13 wherein said continuous film of dielectric material comprises a polymer film having opposed surfaces and being metallized on one surface and presenting a black appearance at the other surface, whereby, when the electrode is extended, the metallized surface is in capacitive contact with the dielectric layer and said other surface presents a black appearance to the viewer;

wherein said colored screen segments are arranged in adjacent groups of four segments per group, having the appearance of three primary colors and white.

15. A video display according to claim 14 wherein said color screen segments are light-transmissive and are colored to have a similar hue by either transmitted or reflected light, whereby said display is viewable by reflected ambient light or transmitted applied light, depending upon ambient illumination levels.

16. A video display according to claim 15 wherein said colored screen is formed from continuous film material.

17. A flat-panel, multi-color, video display manufactured by a method according to claim 16.

18. A method of manufacturing a reflective, thin-panel, multicolor video display having a layered structure and employing light-modulating capacitive pixels, comprising:

I) forming a movable electrode shutter layer from a continuous film of flexible material to have a composite array of movable electrodes, said movable electrodes each having;

a) a pigmentable reflective surface disposable toward the viewer;

b) an open, retracted position providing a clear light path past the movable electrode; and

c) a second, extended position in which said light path is occluded by the movable electrode and the movable electrode'"'"'s reflective surface is disposed toward the viewer;

ii) forming a dielectric layer from a continuous film of dielectric material to comprise a transparent, sheet-like dielectric member in capacitive contact with the movable electrodes in said extended position of each said movable electrode;

iii) forming a light-transmissive control electrode layer disposed in electrostatic engagement with a second surface of said dielectric member to control said movable electrodes;

whereby said movable electrodes, said dielectric member and said control electrodes provide an array of light-modulating capacitors;

iv) providing drive circuitry to apply drive voltages selectively between said fixed electrodes and said movable electrodes to effect movement of selected movable electrodes; and

v) providing a reflective color screen layer disposed adjacent to said shutter layer and behind said shutter layer with respect to said viewer, said color screen layer being composed of a mosaic of reflective colored screen segments individually configured and dimensioned to correspond with said capacitive pixels, adjacent said segments having different colors to provide multi-color display capabilities;

whereby multicolored images can be selectively displayed by electronic manipulation of said movable electrodes.