Patent ID: 7009716

Claim:
A system for monitoring an optical output/wavelength of a light beam emitted from a laser source, comprising: a laser source control means for controlling the laser source, wherein the light beam travels along a propagation path with a divergence angle with respect to an optical axis; an optical output monitoring unit located within the divergence angle of the light beam for receiving a portion of the light beam and for sensing an intensity of the light beam at a predetermined location for receiving predetermined portions of the light beam, thereby obtaining an optical output signal; a filtering unit for filtering the light beam; an optical wavelength monitoring unit located within the divergence angle of the light beam for receiving the other portion of the light beam not shielded by the optical output monitoring unit and for sensing the wavelength generated from the filtering unit, thereby obtaining a wavelength signal; a thermo-electric cooler (TEC) control means for controlling a TEC in order to constantly maintain the laser source to have a predetermined temperature; a temperature control means for controlling a heater and a thermistor to set an etalon to a predetermined temperature independently on the maintained temperature of laser source by the TEC, wherein the heater is attached on the filtering unit on the air gap space on the TEC and the thermistor is attached on the heater; a comparison means for comparing the optical output signal and the wavelength signal; and a processing means for comparing values of the compared signals with a preset value to control an input current or a temperature of the laser source.