Circuit for switching of laser diode, has at least one laser diode and control unit for light power of switched-on laser diode, which in switched-off state controls output rest current below threshold current of laser diode

摘要

Circuit (5) for on/off switching of laser diode (10) contains at least one laser diode and control unit for its light power in switched-on state, and in switched-off state controls output rest current below threshold current of laser diode. Control unit contains photodiode (20), optically coupled with laser diode, and current source (50), controlled in dependence on output rest current. Photodiode is coupled to first current source (90) only in switched-on state, while controlled current source (50) is linked to second current source (100) only in switched-off state.