Continuously variable color display device

• US 4,845,481 A
• Filed: 10/24/1986
• Issued: 07/04/1989
• Est. Priority Date: 01/08/1986
• Status: Expired due to Term

• Current Assignee: Texas Digital Systems, Inc. (NCR Voyix Corporation)
• Original Assignee: Karel Havel
• Inventors: Havel, Karel
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US06/922,847
• Time in Patent Office: 984 Days
• Field of Search: 340/701, 340/702, 340/703, 340/762, 340/756, 340/782, 340/793, 340/815.04, 340/815.1, 340/767
• US Class Current: 345/46
• CPC Class Codes: G04G 21/025 for measuring physiological data
• CPC Class Codes: G04G 9/12 using light valves, e.g. liquid crystals

Abstract

A variable color display device comprises a plurality of display areas arranged in a 7-segment font. Each display area includes at least two light emitting diodes for emitting upon activation light signals of respectively different primary colors and means for blending the light signals within the display area to obtain a composite light signal of a composite color. The light emitting diodes are selectively activated by pulses of substantially constant amplitude to display desired characters. Color control selectively controls the durations of the pulses to control the portions of the primary colors, to thereby control the color of the composite light signal.

Claims

1. A method for controlling a color of a variable color display device which comprises a plurality of display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a plurality of light sources for emitting upon activation light signals of respectively different primary colors and means for combining said light signals to obtain a composite light signal of a composite color, by exhibiting a selected display unit by repeatedly substantially simultaneously activating the light sources in selected display areas for brief time intervals to cause the light sources to emit light signals of said primary colors, and by selectively controlling the durations of the time intervals of activation of the light sources in the selected display areas to control the portions of the primary color light signals emitted therefrom, to thereby control the color of the exhibited display unit.

2. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a plurality of light sources or emitting upon activation light signals of respectively different primary colors and means for combining said light signals to obtain a composite light signal of a composite color;

means for exhibiting a selected display unit by repeatedly substantially simultaneously activating the light sources in selected display areas by pulses of a substantially constant amplitude for causing the light sources to emit light signals of said primary colors; and

color control means for selectively controlling the durations of the pulses applied to the light sources in the selected display areas to control the portions of the primary color light signals emitted therefrom, to thereby control the color of the exhibited display unit.

3. A method of controlling a color of a variable color display device which comprises a plurality of display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a plurality of light emitting diodes for emitting when forwardly biased light signals of respectively different primary colors and means for combining said light signals to obtain a composite light signal of a composite color, by exhibiting a selected display unit by repeatedly substantially simultaneously forwardly biasing the light emitting diodes in selected display areas for brief time intervals to cause the light emitting diodes to emit light signals of said primary colors, and by selectively controlling the durations of the time intervals of forward biasing of the light emitting diodes in the selected display areas to control the portions of the primary color light signals emitted therefrom, to thereby control the color of the exhibited display unit.

4. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a plurality of light emitting diodes for emitting when forwardly biased light signals of respectively different primary colors and means for combining said light signals to obtain a composite light signal of a composite color;

means for exhibiting a selected display unit by repeatedly substantially simultaneously forwardly biasing said light emitting diodes in selected display areas by pulses of a substantially constant voltage amplitude for causing the light emitting diodes to emit light signals of said primary colors; and

color control means for selectively controlling the durations of the pulses applied to the light emitting diodes in the selected display areas to control the portions of the primary color light signals emitted therefrom, to thereby control the color of the exhibited display unit.

5. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a first light source for emitting upon activation light signals of a first color, a second light source for emitting upon activation light signals of a second color, a third light source for emitting upon activation light signals of a third color, and means for combining said light signals of said first color, said second color, and said third color to obtain a composite light signal of a composite color;

means for exhibiting a selected display unit by repeatedly activating first light sources in selected display areas by a first pulse of a substantially constant amplitude for causing the first light sources to emit light signals of said first color, by repeatedly activating second light sources in the selected display areas by a second pulse of a substantially constant amplitude for causing the second light source to emit light signals of said second color, and by repeatedly activating third light sources in the selected display areas by a third pulse of a substantially constant amplitude for causing the third light sources to emit light signals of said third color;

said first pulse, said second pulse, and said third pulse starting substantially simultaneously; and

color control means for selectively terminating said first pulse, said second pulse, and said third pulse to control their respective durations, to control the portions of the light signals of said first color, of said second color, and of said third color emitted from the selected display areas, to thereby control the color of the exhibited display unit.

6. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern for selectively exhibiting a plurality of display units, each said display area including a first light emitting diode for emitting when forwardly biased light signals of a first color, a second light emitting diode for emitting when forwardly biased light signals of a second color, at third light emitting diode for emitting when forwardly biased light signals of a third color, and means for combining said light signals of said first color, said second color, and said third color to obtain a composite light signal of a composite color;

means for exhibiting a selected display unit by repeatedly forwardly biasing first light emitting diodes in selected display areas by a first pulse of a substantially constant voltage amplitude for causing the first light emitting diodes to emit light signals of said first color, by repeatedly forwardly biasing second light emitting diodes in the selected display areas by a second pulse of a substantially constant voltage amplitude for causing the second light emitting diodes to emit light signals o said second color, and by repeatedly forwardly biasing third light emitting diodes in the selected display areas by a third pulse of a substantially constant voltage amplitude for causing the third light emitting diodes to emit light signals of said third color;

said first pulse, said second pulse, and said third pulse starting substantially simultaneously; and

color control means for selectively terminating said first pulse, said second pulse, and said third pulse to control their respective durations, to control the portions of the light signals of said first color, of said second color, and of said third color emitted from the selected display areas, to thereby control the color of the exhibited display unit.

7. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern, each said display area including a first light source for emitting upon activation light signals of a first primary color, a second light source for emitting upon activation light signals of a second primary color, and means for combining said light signals in each said display area to obtain a composite light signal of a composite color;

a decoder for selectively activating groups of said display areas to exhibit one of a plurality of display units;

a first bus to which the first light sources are commonly coupled for enabling, upon activation of said first bus, the first light sources in the display areas activated by said decoder to be illuminated in said first color;

a second bus to which the second light sources are commonly coupled for enabling, upon activation of said second bus, the second light sources in the display areas activated by said decoder to be illuminated in said second color;

means for repeatedly activating said first bus and said second bus by substantially simultaneously applying thereto pulses of a substantially constant amplitude, respectively, for causing the light sources in the display areas activated by said decoder to emit light signals of said primary colors; and

color control means for selectively controlling the durations of the pulses respectively applied to said first bus and to said second bus for controlling the portions of said primary colors, to thereby control the color of the exhibited display unit.

8. A variable color display device comprising:

a plurality of variable color display areas arranged in a pattern, each said display area including a first light source for emitting upon activation light signals of a first primary color, a second light source for emitting upon activation light signals of a second primary color, a third light source for emitting upon activation light signals of a third primary color, and means for combining said light signals in each said display area to obtain a composite light signal of a composite color;

a decoder for selectively activating groups of said display areas to exhibit one of a plurality of display units;

a first bus to which the first light sources are commonly coupled for enabling, upon activation of said first bus, the first light sources in the display areas activated by said decoder to be illuminated in said first color;

a second bus to which the second light sources are commonly coupled for enabling, upon activation of said second bus, the second light sources in the display areas activated by said decoder to be illuminated in said second color;

a third bus to which the third light sources are commonly coupled for enabling, upon activation of said third bus, the third light sources in the display areas activated by said decoder to be illuminated in said third color;

means for repeatedly activating said first bus, said second bus, and said third bus by substantially simultaneously applying thereto pulses of a substantially constant amplitude, respectively, for causing the light sources in the display areas activated by said decoder to emit light signals of said primary colors; and

color control means for selectively controlling the durations of the pulses respectively applied to said first bus, to said second bus, and to said third bus for controlling the portions of said primary colors, to thereby control the color of the exhibited display unit.