Patent ID: 7269192
Filing Date: 2007-09-11
Classification: G05D,H01S

Abstract:
1. A semiconductor laser module, comprising: (a) an optical assembly including, a laser diode for emitting light within a predetermined wavelength range at a temperature by providing a driving signal thereto, a temperature sensor for sensing said temperature of said laser diode, a heater for simulating a self-heating of said laser diode by providing a supply current, and a thermoelectric cooler for controlling said temperature of said laser diode, said thermoelectric cooler mounting said semiconductor laser diode, said temperature sensor and said heater thereon; and (b) a controller including, a memory means for preserving a predetermined temperature range in a digital form, a digital to analog converter for converting said predetermined temperature range preserved in said memory means to values in an analog form and for outputting, to said window comparator, said values converted from said digital form, a window comparator for comparing said temperature of said laser diode sensed by said temperature sensor with said values, said window comparator outputting a switching signal when said temperature of said laser diode falls within said predetermined range, and a first switch connected to said heater, said first switch having a normally close configuration and turning off by receiving said switching signal from said window comparator, thereby shutting off said supply current to said heater.