US3780340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light source with selectable intensity bandwidth
Assignee: Analog Monitors Inc
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Filing: 1971-06-18
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Granted: 1973-12-18
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Expires: 1991-06-18
Abstract
Abstract A light source having a selectable intensity bandwith comprising a lamp, a photosensitive element responsive to the lamp, switching means responsive to the photosensitive element for energizing the lamp below a first selected intensity and for deenergizing the lamp above a second selected intensity, the first and second selected intensities defining the intensity bandwith.
Inventors
- 👤 W Munro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:28
CPC Classifications
H; H05; H05B; H05B47/00; H05B47/10; H05B47/105; H05B47/11; Y; Y02; Y02B; Y02B20/00; Y02B20/40
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
163 words
A light source having a selectable intensity bandwidth comprising in combination: a. a lamp; b. a power supply for energizing said lamp; c. electrical switching means connected between said power supply and said lamp for switching power on to said lamp below a first selected light intensity and for switching power off to said lamp above a second selected light intensity, said first and second intensities defining said intensity bandwidth, said switching means comprising: 1. an electrical resistance bridge having said power supply connected across its input; 2. a photosensitive resistance element responsive to light emitting from said lamp forming one arm of said bridge; 3. an operational amplifier having its input connected across the output of said bridge; 4. a switching transistor having its base connected to the output of said amplifier and its collector to said lamp; and 5. a resistance feedback loop between the output of said amplifier and the noninverting input of said amplifier for establishing said intensity bandwidth.
Claim 2
Dependent Claim
163 words
A light source having a selectable intensity bandwidth comprising in combination: a. a lamp; b. a power supply for energizing said lamp; c. electrical switching means connected between said power supply and said lamp for switching power on to said lamp below a first selected light intensity and for switching power off to said lamp above a second selected light intensity, said first and second intensities defining said intensity bandwidth, said switching means comprising: 1. an electrical resistance bridge having said power supply connected across its input; 2. a photosensitive resistance element responsive to light emitting from said lamp forming one arm of said bridge; 3. an operational amplifier having its input connected across the output of said bridge; 4. a switching transistor having its base connected to the output of said amplifier and its collector to said lamp; and 5. a resistance feedback loop between the output of said amplifier and the noninverting input of said amplifier for establishing said intensity bandwidth.
Claim 3
Dependent Claim
17 words
a photosensitive resistance element responsive to light emitting from said lamp forming one arm of said bridge;
Claim 4
Dependent Claim
17 words
a photosensitive resistance element responsive to light emitting from said lamp forming one arm of said bridge;
Claim 5
Dependent Claim
19 words
The apparatus of claim 1 wherein said resistance feedback loop comprises a variable resistance for varying said intensity bandwidth.
Claim 6
Dependent Claim
25 words
The apparatus of claim 1 wherein one resistance arm of said bridge is a variable resistance for varying the mean level of said intensity bandwidth.
Claim 7
Dependent Claim
13 words
an operational amplifier having its input connected across the output of said bridge;
Claim 8
Dependent Claim
13 words
an operational amplifier having its input connected across the output of said bridge;
Claim 9
Dependent Claim
20 words
a switching transistor having its base connected to the output of said amplifier and its collector to said lamp; and
Claim 10
Dependent Claim
20 words
a switching transistor having its base connected to the output of said amplifier and its collector to said lamp; and
Claim 11
Dependent Claim
25 words
The apparatus of claim 2 wherein one resistance arm of said bridge is a variable resistance for varying the mean level of said intensity bandwidth.
Claim 12
Dependent Claim
22 words
a resistance feedback loop between the output of said amplifier and the noninverting input of said amplifier for establishing said intensity bandwidth.
Claim 13
Dependent Claim
22 words
a resistance feedback loop between the output of said amplifier and the noninverting input of said amplifier for establishing said intensity bandwidth.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |