US3793579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Autoionization spectrometer
Assignee: United States Department of the Army
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Filing: 1972-06-02
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Granted: 1974-02-19
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Expires: 1992-06-02
Abstract
Abstract A spectrometer is provided for directly obtaining the autoionization energy levels within a gas laser and for observing decay probabilities to lower stable energy levels. A laser cavity is periodically interrupted by a rotating chopper wheel. Simultaneously, a probe within the laser plasma is continuously scanned across a ramp potential for attracting or repelling electrons in the plasma ground state. The laser energy in the autoionization state which varies with the chopper wheel rate is sensed by the probe circuit, isolated, amplified, and ultimately recorded as a scalar function of the modulation voltage input. Thus, the population density of the autoionization energy levels for various laser energy levels is obtainable across the frequency range of the chopper wheel.
Inventors
- 👤 C Cason
- 👤 J Perkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:55
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/11; H01S3/1123; H01S3/121
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
309 words
An autoionization spectrometer for measuring the depletion of electrons within the velocity distribution function which excites autoionization energy levels of a laser comprising: a gas laser having a resonant cavity for generating pulses of laser energy, a Langmuir probe coupled to said laser cavity for providing an output signal in response to ground state electron density within said cavity, a motor driven chopper wheel disposed for rotation within said laser cavity for intermittently interrupting lasing action thereof and thereby forming a variable output pulse repetition rate, an isolation amplifier having input terminals and an output, a resistance connected across said input terminals of said isolation amplifier, a ramp generator for providing a ramp voltage output, a transformer having the secondary coupled between said ramp generator and one side of said resistor, the other side of said resistor being connected to said probe for coupling said ramp voltage to said probe and for coupling probe output signals across the input of said isolation amplifier, a signal generator conNected to the primary of said transformer for coupling a high frequency modulation level onto said ramp voltage, a narrow-band amplifier having an output and having an input coupled to the output of said isolation amplifier, phase sensitive means having first and second inputs and an output, said first input being coupled to the output of said narrow-band amplifier, a light source adjacent one side of said chopper wheel, a photo detector coaxial with said light source on the other side of said chopper wheel for receiving pulses of light energy simultaneously with output pulses of said laser, an output of said phototube being coupled to said second input of said phase sensitive means for coupling the chopper wheel pulse repetition rate thereto, and a recoder coupled to the output of said phase sensitive means for recording a graph of signals coupled thereto.
Claim 2
Dependent Claim
309 words
An autoionization spectrometer for measuring the depletion of electrons within the velocity distribution function which excites autoionization energy levels of a laser comprising: a gas laser having a resonant cavity for generating pulses of laser energy, a Langmuir probe coupled to said laser cavity for providing an output signal in response to ground state electron density within said cavity, a motor driven chopper wheel disposed for rotation within said laser cavity for intermittently interrupting lasing action thereof and thereby forming a variable output pulse repetition rate, an isolation amplifier having input terminals and an output, a resistance connected across said input terminals of said isolation amplifier, a ramp generator for providing a ramp voltage output, a transformer having the secondary coupled between said ramp generator and one side of said resistor, the other side of said resistor being connected to said probe for coupling said ramp voltage to said probe and for coupling probe output signals across the input of said isolation amplifier, a signal generator conNected to the primary of said transformer for coupling a high frequency modulation level onto said ramp voltage, a narrow-band amplifier having an output and having an input coupled to the output of said isolation amplifier, phase sensitive means having first and second inputs and an output, said first input being coupled to the output of said narrow-band amplifier, a light source adjacent one side of said chopper wheel, a photo detector coaxial with said light source on the other side of said chopper wheel for receiving pulses of light energy simultaneously with output pulses of said laser, an output of said phototube being coupled to said second input of said phase sensitive means for coupling the chopper wheel pulse repetition rate thereto, and a recoder coupled to the output of said phase sensitive means for recording a graph of signals coupled thereto.
Claim 3
Dependent Claim
84 words
The apparatus as set forth in claim 1 and further comprising: a quarter-square multiplier having a first input coupled to the output of said narrow-band amplifier and a second input connected to the output of said phase sensitive means, an output of said multiplier being coupled as an autoionization population density input of said recorder, another input of said recorder being connected to said Langmuir probe and responsive to the total energy level thereon for recording a graph of autoionization population density versus energy.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |