US3835331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stable pulsed light source
Assignee: United States Atomic Energy Commission
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Filing: 1973-09-26
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Granted: 1974-09-10
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Expires: 1993-09-26
Abstract
Abstract A pulsed light source is provided for use as a standard source of light for the calibration of photomultiplier tubes and the like. The source utilizes an inexpensive light-emitting diode and produces pulses whose height and length may be adjusted. Temperature stabilization is employed and the diode is operated in the current mode. Typical resolution and stability are 3 and 0.5 percent, respectively.
Inventors
- 👤 J Thorngate
- 👤 P Perdue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:06
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J3/10; H; H03; H03K; H03K3/00; H03K3/02; H03K3/42; H03K3/53; H05; H05B; H05B45/00; H05B45/10; G01J3/28; G01J2003/2866; H05B45/30; H05B45/395
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
167 words
A stable pulsed light source comprising a source of pulses, means for adjusting the pulse height and the pulse length of said pulses, a light-emitting diode, means for connecting the output of said source of pulses directly to said diode, and a comparison circuit connected between said source of pulses and said diode, said comparison circuit including a differential amplifier network connected to said source of pulses, an output transistor connected to said network, a feedback circuit provided with a temperature compensated zener diode connected between said output transistor and said differential amplifier network, and means for providing an adjustable quiescent current to said light-emitting diode connected between a junction of said transistor and zener diode and to said light-emitting diode, said comparison circuit being utilized to compare the current through said light-emitting diode with the input pulses and to control the amount of quiescent current to said light-emitting diode, whereby said light-emitting diode provides a relatively stable pulsed light source with good resolution for calibration purposes.
Claim 2
Dependent Claim
167 words
A stable pulsed light source comprising a source of pulses, means for adjusting the pulse height and the pulse length of said pulses, a light-emitting diode, means for connecting the output of said source of pulses directly to said diode, and a comparison circuit connected between said source of pulses and said diode, said comparison circuit including a differential amplifier network connected to said source of pulses, an output transistor connected to said network, a feedback circuit provided with a temperature compensated zener diode connected between said output transistor and said differential amplifier network, and means for providing an adjustable quiescent current to said light-emitting diode connected between a junction of said transistor and zener diode and to said light-emitting diode, said comparison circuit being utilized to compare the current through said light-emitting diode with the input pulses and to control the amount of quiescent current to said light-emitting diode, whereby said light-emitting diode provides a relatively stable pulsed light source with good resolution for calibration purposes.
Claim 3
Dependent Claim
18 words
The light source set forth in claim 1, wherein said light-emitting diode is a gallium arsenide phosphide diode.
Claim 4
Dependent Claim
51 words
The light source set forth in claim 2, wherein said means for providing an adjustable quiescent current to said light-emitting diode comprises a relatively high resiStance potentiometer and a resistor connected in series between said junction and said light-emitting diode, and a low inductance capacitor connected across said high resistance potentiometer.
Claim 5
Dependent Claim
28 words
The light source set forth in claim 3, wherein said high resistance potentiometer has a resistance of 500 Kohms and said resistor has a resistance of 90.9 ohms.
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) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |