Abstract: Both a system and method are provided for modulating the intensity of an output beam generated by semiconductor laser. The exemplary system includes a source of pulsating current connected to the laser that generates a pulsating beam of laser light, an external modulator having an input that receives the pulsating beam, and an output controlled by pulsating control signal, wherein the output beam transmitted by the external modulator output is modulated by changing a relative phase angle between the pulsating current powering the laser, and the control signal of the external modulator over time. The external modulator may be an intensity-type modulator whose output is controlled by a gate signal having a constant phase, and the source of pulsating current powering the laser may be variable phase in order to modulate the output beam with an external modulator having a simple structure.

Abstract: The present invention relates generally to semiconductor lasers and laser scanning systems and, more particularly, to schemes for controlling wavelength in semiconductor lasers. According to one embodiment of the present invention, a method of minimizing laser wavelength variations in a semiconductor laser is provided. According to the method, one or more of the laser drive currents is configured to comprise a drive portion and a wavelength recovery portion. The wavelength recovery portion of the drive current comprises a recovery amplitude IR that is distinct from the drive amplitude ID and a recovery duration tR that is less than the drive duration tD. The recovery amplitude IR and duration tR are sufficient to recover carrier density distribution distorted by gain compression effects prior to recovery. Additional embodiments are disclosed and claimed.

Abstract: The present invention is directed to a method and system for providing phase modulated current to a semiconductor laser to control beam wavelength. A first current is received into a gain portion of the semiconductor laser and a second current is received into a DBR portion of the semiconductor laser. The second current is phase modulated based upon a required intensity value. An output beam is generated by the semiconductor laser based upon the received first current and the received second current.

Abstract: The present invention is directed to a method and system for providing a three-level current scheme to a semiconductor laser to control beam wavelength and laser temperature. A first current is received into a gain section of the semiconductor laser and at least one other current is received into a DBR and/or phase section of the semiconductor laser. This other current(s) is pulse-width modulated based upon a required temperature value. An output beam is generated by the semiconductor laser based upon the received first current and the received pulse-width modulated current(s).