Techniques for producing a Brillouin laser are provided. According to some aspects, techniques are based on forward Brillouin scattering and a multimode acousto-optic waveguide in which light is scattered between optical modes of the waveguide via the Brillouin scattering. This process may transfer energy from a waveguide mode of pump light to a waveguide mode of Stokes light. This process may be referred to herein as Stimulated Inter-Modal Brillouin Scattering (SIMS). Since SIMS is based on forward Brillouin scattering, laser (Stokes) light may be output in a different direction than back toward the input pump light, and as such there is no need for a circulator or other non-reciprocal device to protect the pump light as in conventional devices.

A laser master-oscillator power-amplifier (MOPA) is operated to provide successive bursts of ultrashort pulses. The pulse-bursts are selected by an optical modulator from a pulse train delivered by the master oscillator prior to amplification in the power amplifier. The optical modulator has a selectively variable transmission specified by an analog voltage signal having a stepped waveform. The voltage signal is delivered by a sequentially-switched parallel switch-array connected in parallel with a parallel DAC having multiple parallel DC voltage outputs corresponding to steps of the stepped waveform.

A laser apparatus, a measurement apparatus, and a measurement method are provided in which the laser apparatus outputs a frequency-modulated laser beam with a plurality of modes and includes: an optical cavity that has a gain medium for amplifying a light to be input, and an optical SSB modulator for shifting a frequency of the light amplified by the gain medium: and a control part that controls the optical SSB modulator to shift a frequency of a light to be input to the optical SSB modulator.

A laser device includes: a master oscillator (100) configured to output a pulse laser beam (L) based on a light emission trigger signal (S21); a delay circuit (153) configured to generate a switching signal (S10) after a predetermined delay time has elapsed since reception of the light emission trigger signal (S21); a high voltage switch (304) configured to generate a high voltage pulse based on the switching signal (S10); an optical shutter (32k) positioned on the optical path of the pulse laser beam (L) and driven based on the high voltage pulse; and a high voltage monitor (151) configured to detect the high voltage pulse and transmit a high voltage pulse sensing signal (S6) to the delay circuit (153). The delay circuit (153) determines the delay time based on the light emission trigger signal (S21) and the high voltage pulse sensing signal (S6).

A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

The present invention relates to a diode laser with external spectrally selective feedback. It is an object of the invention is to provide an external cavity diode laser with wavelength stabilization which allows an increased overall output power in the desired wavelength range. According to the invention, an external cavity diode laser arrangement is disclosed comprising: an active medium positioned inside an internal laser cavity (10), the internal laser cavity (10) comprising an exit facet (12) adapted for outcoupling laser radiation; an external frequency-selective element (14) positioned outside the internal laser cavity (10) and adapted for wavelength stabilization of the laser radiation; a beam divider (16) positioned outside the internal laser cavity (10) and adapted to divide the outcoupled laser radiation (BO) into a first beam (B1) extending along a first beam path (P1) and a second beam (B2) extending along a second beam path (P2), the first beam (B1) having higher radiant intensity than the second beam (B2) and the first beam path (P1) being different from the second beam path (P2); and an intensity control means to control the radiant intensity incident to the external frequency selective element (14); wherein the external frequency-selective element (14) and the intensity control means are arranged in the second beam path (P2). The intensity control means in the second beam path (P2) may comprise a polarization modifying means (18) and a polarizer (20) in order to reduce thermal stress at the frequency-selective element (14).

A laser device (100), being configured for generating laser pulses by Ken lens based mode locking, comprises a laser resonator (10) with a plurality of resonator mirrors (11.1, 11.2, 11.3) spanning a resonator beam path (12), a solid state gain medium (20) being arranged in the laser resonator (10), a Kerr medium device (30) being arranged with a distance from the gain medium (20) in the laser resonator (10), wherein the Kerr medium device (30) includes at least one Ken medium being arranged in a focal range of the resonator beam path and being configured for forming the laser pulses by the nonlinear Kerr effect, and a loss-modulation device (31, 32) having a modulator medium, which is capable of modulating a power loss of the laser pulses generated in the laser resonator (10), wherein the Kerr medium device (30) includes the modulator medium of the loss-modulation device (31, 32) as the at least one Kerr medium having an optical non-linearity being adapted for both of creating the Kerr lens based mode-locking in the laser resonator and modulating the power loss in the laser resonator. Furthermore, a method of generating laser pulses by Kerr lens based mode locking is described, wherein a loss-modulation device (31, 32) is used for both of introducing a Ken effect in the laser resonator (10) and modulating the power loss.

A laser-beam power-modulation system includes an acousto-optic modulator (AOM) to receive a laser beam and separate the laser beam into a primary beam and a plurality of diffracted beams based on an input signal. The power of the primary beam depends on the input signal. The system also includes a slit to transmit the primary beam and dump the plurality of diffracted beams, a controller to generate a control signal based at least in part on feedback indicative of the power of the primary beam or the power of a beam generated using the primary beam, and a driver to generate the input signal based at least in part on the control signal.

An apparatus includes an acousto-optical deflector (AOD) system operative to deflect a beam of laser energy within a two-dimensional scan field. The AOD system includes a first AOD operative to deflect the beam of laser energy along a first axis of the two-dimensional scan field; a second AOD arranged optically downstream of the first AOD, wherein the second AOD is operative to deflect the beam of laser energy along a second axis of the two-dimensional scan field; and a controller operatively coupled to the AOD system. The controller is configured to drive each of the first AOD and the second AOD to deflect the beam of laser energy within the two-dimensional scan field and is further configured to drive the first AOD and the second AOD at at least substantially the same diffraction efficiency.

Systems and methods are described for producing an amplitude-modulated laser pulse train. The laser pulse train can be used to cause fluorescence in materials at which the pulse trains are directed. The parameters of the laser pulse train are selected to increase fluorescence relative to a constant-amplitude laser pulse train. The amplitude-modulated laser pulse trains produced using the teachings of this invention can be used to enable detection of specific molecules in applications such as gene or protein sequencing.