US4856012A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for controlling light output of a pulse-excited laser oscillator
Assignee: Laserfront Technologies Inc
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Filing: 1987-08-04
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Granted: 1989-08-08
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Expires: 2007-08-04
Abstract
Abstract An apparatus for controlling light output of a pulse-excited laser oscillator which detects the energy level of laser light output and controls a driving circuit to interrupt the application of a driving voltage to a flash lamp when the level of laser light output is equal to a predetermined level so that a stable laser light output is obtained in each pulse in real time.
Inventors
- 👤 Hiroo Takenaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:24
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/13; H01S3/131; H01S3/1312
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
118 words
An apparatus for controlling light output of a pulse-excited laser oscillator comprising, means for driving a flash lamp to provide a discharge current therein by applying a driving voltge thereto, means for detecting an energy level of laser light output and means for comparing said energy level with a predetermined value, means for producing an interrupting signal when said energy level is equal to said predetermined value, and means for controlling said means for driving to interrupt the application of said driving voltage to said flash lamp when said interrupting signal is produced , the interruption of said driving voltage interrupting the flow of discharge current in said flash lamp, resulting in the interruption of a laser oscillation.
Claim 2
Independent Claim
118 words
An apparatus for controlling light output of a pulse-excited laser oscillator comprising, means for driving a flash lamp to provide a discharge current therein by applying a driving voltge thereto, means for detecting an energy level of laser light output and means for comparing said energy level with a predetermined value, means for producing an interrupting signal when said energy level is equal to said predetermined value, and means for controlling said means for driving to interrupt the application of said driving voltage to said flash lamp when said interrupting signal is produced , the interruption of said driving voltage interrupting the flow of discharge current in said flash lamp, resulting in the interruption of a laser oscillation.
Claim 3
Dependent Claim
163 words
An apparatus for controlling light output of a pulse-excited laser oscillator according to claim 1, wherein said means for driving comprises a plurality of capacitors which are charged up to said driving voltage, and a SCR which is turned on by a control signal applied to a gate terminal thereof to apply said driving voltage to said flash lamp, said means for detecting comprises a PIN photodiode for outputting an electric signal corresponding to said energy level of laser light output, and an integrating circuit including an integrating capcitor to be charged by said electric signal and a switch which is turned on when said interrupting signal is produced, resulting in the discharging of said integrating capacitor, and said means for controlling comprises an interrupting capacitor to be charged up to a voltage level which is larger than said driving voltage, and a SCR which is turned on by said interrupting signal whereby said SCR in said means for driving is turned off.
Claim 4
Dependent Claim
42 words
An apparatus for controlling light output of a pulse-excited laser oscillator according to claim 2, wherein said PIN photodiode is provided to receive a part of laser light output emitted from a side opposite to an output side of a laser medium.
Claim 5
Dependent Claim
38 words
An apparatus for controlling light output of a pulse-excited laser oscillator according to claim 2, wherein said PIN photodiode is provided to receive a part of laser light output emitted from an output side of a laser medium.
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) | 1992-08-07 | 1993-02-06 | 1993-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-07 | 1997-02-06 | 1997-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-07 | 2001-02-06 | 2001-08-08 | $7700.00 | Window Closed / Lapsed |