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US4182977A Expired / Lapsed US ⏱️ 0.0 years remaining

Constant output light emitting device

Assignee: Optron Inc
•
Filing: 1978-06-01
•
Granted: 1980-01-08
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Expires: 1998-06-01
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Abstract

Abstract A light emitting device which provides substantially constant output power is disclosed. The light emitting device includes a light emitter and a compensating circuit for supplying current to the light emitter so that at any given time an increase in electric current produces a corresponding increase in light intensity. The compensating circuit includes a following circuit for supplying current to the light emitter, a differential isolation amplifier for driving the following circuit and a light sensor and its related circuitry. The light sensor is in proximity to and substantially to the side of the light emitter and is connected in a feedback relationship to the differential isolation amplifier. In one arrangement, the compensating circuit is an integrated circuit, and the light emitter and compensating circuit are mounted on a header. The header forms a recess, and the light emitter is mounted on the header in the recess. In one arrangement, a substantially clear overcoat substantially covers both the light sensor and the light emitting surface of the light emitter in such a way that substantially all of the light emitted from the light emitter is transmitted through the overcoat, but some of the light is reflected to the light sensor. In one arrangement, the integrated circuit also includes circuitry to limit the current supplied to the light emitter to a predetermined maximum level.

Inventors

  • 👤 Robert S. Stricklin, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 04:54
CPC Classifications
H; H10; H10W; H10W90/00; H05; H05B; H05B45/00; H05B45/10; H05B45/12; H05B45/30; H05B45/395; H05B45/40; H05B47/00; H05B47/10; H10W90/701; H10W90/751; H10W90/753; Y; Y02; Y02B; Y02B20/00; Y02B20/30

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 264 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit comprising an integrated circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; means for electrically connecting the compensating circuit to the power supply; a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein part of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter; and a header for mounting electrical components, wherein the light emitter and the compensating circuit are mounted on the header; wherein the header forms a recess for mounting the light emitter, and the light emitter is mounted on the header in the recess, and wherein the substantially clear overcoat substantially covers both the light sensor and the light emitting surface of the light emitter.
Claim 2
Dependent Claim 264 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit comprising an integrated circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; means for electrically connecting the compensating circuit to the power supply; a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein part of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter; and a header for mounting electrical components, wherein the light emitter and the compensating circuit are mounted on the header; wherein the header forms a recess for mounting the light emitter, and the light emitter is mounted on the header in the recess, and wherein the substantially clear overcoat substantially covers both the light sensor and the light emitting surface of the light emitter.
Claim 3
Dependent Claim 24 words
A light emitting device according to claim 1 wherein substantially all of the light emitted from the light emitter is transmitted through the overcoat.
Claim 4
Dependent Claim 361 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter consisting of a light emitting diode for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit comprising an integrated circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including in combination: a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; a following circuit for supplying current to the light emitter; a differential isolation amplifier for driving the following circuit, having a first input and a second input; and a circuit for driving the light sensor, wherein the circuit for driving the light sensor is connected in a feedback relationship to the first input of the differential isolation amplifier whereby the integrated circuit is responsive to the light sensed by the light sensor when the second input to the differential isolation amplifier is at a predetermined voltage level; means for electrically connecting the compensating circuit to the power supply; and a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein substantially all of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter; and a header for mounting electrical components, wherein the light emitter and the compensating circuit are mounted on the header; wherein the header forms a recess for mounting the light emitter, and the light emitter is mounted on the header in the recess, and wherein the substantially clear overcoat substantially covers both the light sensor and the light emitting surface of the light emitter.
Claim 5
Dependent Claim 361 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter consisting of a light emitting diode for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit comprising an integrated circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including in combination: a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; a following circuit for supplying current to the light emitter; a differential isolation amplifier for driving the following circuit, having a first input and a second input; and a circuit for driving the light sensor, wherein the circuit for driving the light sensor is connected in a feedback relationship to the first input of the differential isolation amplifier whereby the integrated circuit is responsive to the light sensed by the light sensor when the second input to the differential isolation amplifier is at a predetermined voltage level; means for electrically connecting the compensating circuit to the power supply; and a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein substantially all of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter; and a header for mounting electrical components, wherein the light emitter and the compensating circuit are mounted on the header; wherein the header forms a recess for mounting the light emitter, and the light emitter is mounted on the header in the recess, and wherein the substantially clear overcoat substantially covers both the light sensor and the light emitting surface of the light emitter.
Claim 6
Dependent Claim 29 words
A light emitting device according to claim 3 wherein the integrated circuit further comprises means for limiting the current supplied to the light emitter to a predetermined maximum level.
Claim 7
Dependent Claim 107 words
A light emitting device according to claim 3 to be used in conjunction with a logic gate wherein the predetermined voltage level of the second input corresponds to a first output voltage level of the logic gate and wherein the light emitting device is switched off when the second input of the differential isolation amplifier is at a second predetermined voltage level, the second predetermined voltage level corresponding to a second output voltage level of the logic gate whereby the logic gate can switch the light emitting device on and off when the output of the logic gate controls the second input to the differential isolation amplifier.
Claim 8
Dependent Claim 287 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including in combination: a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; a following circuit for supplying current to the light emitter; a differential isolation amplifier for driving the following circuit, having a first input and a second input; and a circuit for driving the light sensor, wherein the circuit for driving the light sensor is connected in a feedback relationship to the first input of the differential isolation amplifier whereby the compensating circuit is responsive to the light sensed by the light sensor when the second input to the differential isolation amplifier is at a predetermined voltage level; means for electrically connecting the compensating circuit to the power supply; and a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein substantially all of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter.
Claim 9
Dependent Claim 287 words
A light emitting device to be used in conjunction with a power supply, comprising in combination: a light emitter for emitting light when supplied with electric current, wherein an increase in electric current supplied to the light emitter increases the output light intensity; a compensating circuit powered by the power supply, electrically connected to the light emitter for supplying current to the light emitter, the compensating circuit including in combination: a light sensor in proximity to and substantially to the side of the light emitter wherein the compensating circuit is responsive to the light intensity sensed by the light sensor, increasing the current supplied to the light emitter as the intensity of the light sensed decreases; a following circuit for supplying current to the light emitter; a differential isolation amplifier for driving the following circuit, having a first input and a second input; and a circuit for driving the light sensor, wherein the circuit for driving the light sensor is connected in a feedback relationship to the first input of the differential isolation amplifier whereby the compensating circuit is responsive to the light sensed by the light sensor when the second input to the differential isolation amplifier is at a predetermined voltage level; means for electrically connecting the compensating circuit to the power supply; and a substantially clear overcoat substantially covering the light emitting surface of the light emitter wherein substantially all of the light emitted from the light emitter is transmitted through the overcoat and part of the light emitted is reflected by the overcoat to the light sensor, whereby the intensity of light transmitted through the overcoat when the light emitting device is on remains substantially constant over the useful life of the light emitter.
Claim 10
Dependent Claim 29 words
A light emitting device according to claim 6 wherein the compensating circuit further comprises means for limiting the current supplied to the light emitter to a predetermined maximum level.
Claim 11
Dependent Claim 107 words
A light emitting device according to claim 6 to be used in conjunction with a logic gate wherein the predetermined voltage level of the second input corresponds to a first output voltage level of the logic gate and wherein the light emitting device is switched off when the second input of the differential isolation amplifier is at a second predetermined voltage level, the second predetermined voltage level corresponding to a second output voltage level of the logic gate whereby the logic gate can switch the light emitting device on and off when the output of the logic gate controls the second input to the differential isolation amplifier.

References Cited (Backward Citations)

US3796916A Cited
US3755679A Cited
US3931513A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-01-07 1983-07-09 1984-01-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-01-07 1987-07-09 1988-01-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-01-07 1991-07-09 1992-01-08 $7700.00 Window Closed / Lapsed

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