Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Reexamination Certificate
2007-01-23
2007-01-23
Luu, Thanh X. (Department: 2878)
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
C372S033000, C372S038010, C372S029011
Reexamination Certificate
active
10294469
ABSTRACT:
An automatic power control system provides a control signal that regulates the output power of at least one laser diode. Coarse adjustment of the control signal is provided by a first means, preferably a digital variable resistor, while fine adjustment and compensation is provided by a second means, preferably by a digital-to-analog converter that receives an input signal proportional to a sensed control system parameter. The control system includes an operational amplifier having a first input coupled to sense output power, and a second input coupled to a DAC to provide finer resolution control. Memory can store system parameter or system parameter variations that can be coupled to the DAC and/or variable resistor to enhance system stability over ambient variations.
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Chambers Peter
Judkins, III Joseph James
Kunst David
Lewandowski Robert James
Lindsay Tom
Dorsey & Whitney LLP
Luu Thanh X.
Micrel Incorporated
Stratos Lightware, Inc.
Yam Stephen
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