Patent ID: 6137816
Filing Date: 2000-10-24
Classification: H01L,H01S

Abstract:
A power source control apparatus for a laser diode, comprising:a laser diode having an anode and a cathode;a switching element connected in parallel between said anode and said cathode of said laser diode, said switching element having a forward voltage drop lower than a forward voltage drop of said laser diode;a shorting circuit that turns said switching element on so as to short-circuit said anode and cathode of said laser diode when said shorting circuit receives no laser output command signal for making said laser diode output a laser beam, said shorting circuit turning said switching element off so as to make said laser diode output the laser beam when said shorting circuit receives said laser output command signal; and,a constant current source circuit that supplies current to the laser diode, the current being switched to one of said laser diode and said switching element by said shorting circuit.