Multicolor display device

• US 4,686,425 A
• Filed: 08/04/1986
• Issued: 08/11/1987
• Est. Priority Date: 04/28/1986
• Status: Expired due to Fees

• Current Assignee: Karel Havel
• Original Assignee: Karel Havel
• Inventors: Havel, Karel
• Primary Examiner(s): Dixon, Harold
• Application Number:
  US06/892,837
• Time in Patent Office: 372 Days
• Field of Search: 250/205, 250/209, 250/552, 250/553, 315/152, 315/153, 315/154, 315/155, 315/156, 315/157, 315/158, 315/130, 315/131, 315/133, 315/134, 357/19
• US Class Current: 315/152
• CPC Class Codes: H05B 3/38 Powder conductors
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/22 using optical feedback

Abstract

A multicolor display device having seven illuminated optically stable states includes three triads of associated electro-optical components. In each triad, a light sensor is electrically coupled with a display light emitting diode and auxiliary light emitting diode. An optical feedback is established in each triad between the auxiliary light emitting diode and the light sensor tending to maintain its associated display light emitting diode either in the illuminated or extinguished condition. Light signals of respectively different colors emitted by three display light emitting diodes are blended to obtain a composite light signal of a color in accordance with the conditions of respective display light emitting diodes.

Claims

1. A multicolor display device comprising:

three display light emitting diodes for emitting upon activation light signals of respectively different primary colors, each said display light emitting diode being capable either of an illuminated or extinguished condition;

means for blending said light signals to obtain a composite light signal of a color in accordance with the condition of respective display light emitting diodes;

three auxiliary light emitting diodes respectively electrically coupled to said display light emitting diodes, thereby forming three pairs of associated display light emitting diode and auxiliary light emitting diode;

three light sensors respectively electrically serially coupled to said pairs of associated display light emitting diode and auxiliary light emitting diode, each said light sensor having resistance variable with illumination; and

three chambers secured from the presence of ambient light for respectively accommodating the pairs of serially coupled light sensor and auxiliary light emitting diode, in each said pair the active area of said light sensor being oriented to intercept light signals emitted by its serially coupled auxiliary light emitting diode to exert a toggle effect by varying the resistance of said light sensor in a sense tending to maintain its serially coupled display light emitting diode either in the illuminated or extinguished condition.

2. A multicolor display device comprising:

a housing having a base and two opaque walls secured to said base, said walls being tapered in the thickness toward the top of said housing and having inner inclined surfaces defining a light blending cavity therebetween;

three display light emitting diodes disposed in said light blending cavity for emitting upon activation light signals of respectively different primary colors, each said display light emitting diode being capable either of an illuminated or extinguished condition;

means for blending within said light blending cavity said light signals to obtain a composite light signal of a color in accordance with the conditions of respective display light emitting diodes;

three auxiliary light emitting diodes respectively electrically coupled to said display light emitting diodes, thereby forming three pairs of associated display light emitting diode and auxiliary light emitting diode;

three light sensors respectively electrically serially coupled to said pairs of associated display light emitting diode and auxiliary light emitting diode, each said light sensor having resistance variable with illumination; and

three chambers disposed in said opaque walls and secured from the presence of ambient light for respectively accommodating the pairs of serially coupled light sensor and auxiliary light emitting diode, in each said pair the active area of said light sensor being oriented to intercept light signals emitted by its serially coupled auxiliary light emitting diode to exert a toggle effect by varying the resistance of said light sensor in a sense tending to maintain its serially coupled display light emitting diode either in the illuminated or extinguished condition.