Patent ID: 7502394

Claim:
A system for modulating the intensity of an output beam generated by a semiconductor laser that generates a pulsating beam of laser light, said system comprising: a source of pulsating current connected to said laser, said source of pulsating current being structured such that said pulsating current has a constant duty cycle of no more than 50%, an external modulator; a source of pulsating control signal operatively (i) connected to the external modulator, and (ii) arranged such that a relative phase angle between said pulsating current and said control signal changes over time; wherein the external modulator is structured to: (A) be controlled by the pulsating control signal, and (B) to provide an output beam modulated by the changing relative phase angle between said pulsating current and said control signal over time, said external modulator having (i) an input that receives said pulsating beam of laser light, and (ii) an output that provides the modulated output beam.