US5598040A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser writer having high speed high current laser driver
Assignee: Eastman Kodak Co
•
Filing: 1995-05-31
•
Granted: 1997-01-28
•
Expires: 2015-05-31
Abstract
Abstract A diode laser writer having a high speed, high current, precision laser driver provides for switching a constant current source between a write laser and a dump load. An inductor is provided in a leg of the circuit such that the inductor and the constant current source form a series circuit with whichever of the dump load and the write laser that is switched ON. The inductor keeps the current constant because the inductor produces an e.m.f. counter to the e.m.f. of the load inductance. The added inductance will generate an e.m.f. counter to that of the load inductance, serving to augment the compliance voltage. The overall effect of the added inductor is to restore the constant current property of the circuit.
Inventors
- 👤 William R. Markis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:35
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/04; H01S5/042; H01S5/06; H01S5/062; H01S5/06209; H01S5/06216
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
121 words
A laser writer having a laser driver including: at least one write laser; a dump load associated with said at least one write laser; a constant current source; switch means for alternatively connecting the constant current source to the at least one write laser and to the dump load associated with the at least one write laser; and an inductor positioned so as to be connected between the constant current source and the at least one write laser when the at least one write laser is connected to the constant current source by the switch means, and between the constant current source and the dump load when the dump load is connected to the constant current source by the switch means.
Claim 2
Dependent Claim
121 words
A laser writer having a laser driver including: at least one write laser; a dump load associated with said at least one write laser; a constant current source; switch means for alternatively connecting the constant current source to the at least one write laser and to the dump load associated with the at least one write laser; and an inductor positioned so as to be connected between the constant current source and the at least one write laser when the at least one write laser is connected to the constant current source by the switch means, and between the constant current source and the dump load when the dump load is connected to the constant current source by the switch means.
Claim 3
Dependent Claim
17 words
A laser writer as set forth in claim 1 wherein the dump load is a dummy laser.
Claim 4
Dependent Claim
119 words
A laser writer having a laser driver including: a plurality of independently-modulated diode lasers; a dump load associated with each of said plurality of write lasers; a constant current source; switch means for alternatively connecting the constant current source to the plurality of write lasers and to the dump load associated with the plurality of write lasers; and an inductor positioned so as to be connected between the constant current source and the plurality of write lasers when the plurality of write lasers is connected to the constant current source by the switch means, and between the constant current source and the dump load when the dump load is connected to the constant current source by the switch means.
Claim 5
Dependent Claim
119 words
A laser writer having a laser driver including: a plurality of independently-modulated diode lasers; a dump load associated with each of said plurality of write lasers; a constant current source; switch means for alternatively connecting the constant current source to the plurality of write lasers and to the dump load associated with the plurality of write lasers; and an inductor positioned so as to be connected between the constant current source and the plurality of write lasers when the plurality of write lasers is connected to the constant current source by the switch means, and between the constant current source and the dump load when the dump load is connected to the constant current source by the switch means.
Claim 6
Dependent Claim
42 words
A laser writer as set forth in claim 1 wherein the switch means comprises a pair of switches operable together in opposite states to shuttle current from the constant current source between the at least on write laser and the dump load.
References Cited (Backward Citations)
US3388300A
Cited
US3446984A
Cited
US3700985A
Cited
US3930171A
Cited
US4819242A
Cited
US4743091A
Cited
US5132553A
Cited
US5109460A
Cited
US5333081A
Cited
US5260956A
Cited
US5315606A
Cited
US5488625A
Cited
US5444728A
Cited
EP0678982A2
Cited
US5438581A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-28 | 2000-07-29 | 2001-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-28 | 2004-07-29 | 2005-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-28 | 2008-07-29 | 2009-01-28 | $7700.00 | Window Closed / Lapsed |