The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Mar. 13, 2007

Filed:

Mar. 19, 2004
Applicants:

Tse-hsiang Hsu, Hsinchu, TW;

Pao-ping MA, Hsin Chu, TW;

Inventors:

Tse-Hsiang Hsu, Hsinchu, TW;

Pao-Ping Ma, Hsin Chu, TW;

Assignee:

Mediatek Inc., Hsin-chu, TW;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 11/00 (2006.01);
U.S. Cl.
CPC ...
Abstract

An automatic power controller includes a photo detector for detecting the output power of the laser light source and generating a detection signal, a comparator for comparing the detection signal with a reference signal and outputting a comparison signal, a signal source for providing the reference signal with different voltages representing different output power levels of the laser light source to be set, and a gain-adjustable amplifier for receiving the comparison signal and generating an output signal. The gain of the gain-adjustable amplifier is adjusted so that the voltage difference between the steady-state voltage of the comparison signal and the voltage of the reference signal is kept substantially unchanged regardless of the output power of the laser light source, the occurrence of charging/discharging the capacitor in the comparator is reduced. Therefore the automatic power controller can rapidly reach its new steady state while changing the laser output power.


Find Patent Forward Citations

Loading…