Patent ID: 6590686
Filing Date: 2003-07-08
Classification: H04B

Abstract:
An optical transmitter comprising:a laser diode outputting light as a forward beam and a backward beam; an external modulator modulating said light from said laser diode according to a main signal to output an optical signal; a power monitor detecting power of said optical signal output from said external modulator; a first control unit controlling a drive current for said laser diode so that the power detected by said power monitor becomes constant; a wavelength monitor detecting a wavelength of said backward beam; a second control unit controlling a temperature of said laser diode so that the wavelength detected by said wavelength monitor becomes stable; a current monitor detecting said drive current; and a compensating unit changing the temperature of said laser diode according to a change in said drive current detected by said current monitor so that the wavelength of said light beam becomes constant.