A laser system includes a nonlinear optical (NLO) crystal, wherein the NLO crystal is annealed within a selected temperature range. The NLO crystal is passivated with at least one of hydrogen, deuterium, a hydrogen-containing compound or a deuterium-containing compound to a selected passivation level. The system further includes at least one light source, wherein at least one light source is configured to generate light of a selected wavelength and at least one light source is configured to transmit light through the NLO crystal. The system further includes a crystal housing unit configured to house the NLO crystal.

A laser system includes a seed source optically coupled to an extra cavity harmonic generator system may produce a round, non-astigmatic third harmonic output beam from a nominally round, non-astigmatic, diffraction limited input fundamental beam from the seed source. The system may include a second harmonic generation crystal. An input fundamental beam size is expanded in a non-walkoff direction for the SHG crystal at the SHG crystal input face. A higher harmonic generation crystal has an output face oriented at an oblique angle of incidence in a non-walkoff direction for the HHG crystal such that an output higher harmonic beam size is contracted in this direction. Expansion of the input fundamental beam at the SHG crystal input face exceeds reduction of third harmonic beam at the HHG crystal output face.

A solid-state laser system may include first and second solid-state laser units, a wavelength conversion system, an optical shutter, and a controller. The first solid-state laser unit and the second solid-state laser unit may output first pulsed laser light with a first wavelength and second pulsed laser light with a second wavelength, respectively. The controller may perform first control and second control. The first control may cause the first and second pulsed laser light to enter the wavelength conversion system at a substantially coincidental timing, thereby causing the wavelength conversion system to output third pulsed laser light with a third wavelength converted from the first wavelength and the second wavelength, and the second control may prevent the first and second pulsed laser light from entering the wavelength conversion system at the coincidental timing, thereby preventing the wavelength conversion system from outputting the third pulsed laser light.

A system is described for multi-frequency ultrasonically-encoded optical tomography of target tissue. A light source generates light input signals to the target tissue. An ultrasound transducer array has ultrasound transducers each generating a different time-dependent waveform to form a plurality of ultrasound input signals to an imaging volume within the target tissue. An optical sensor senses scattered light signals from the imaging volume, wherein the scattered light signals include light input signals modulated by acousto-optic interactions with the ultrasound input signals. Spectral analysis of the scattered light signals is performed to create a three-dimensional image map representing biomarker characteristics of the target tissue.

A system is described for multi-frequency ultrasonically-encoded tomography of a target object. One or more probe inputs generate probe input signals to the target object. An ultrasound transducer array is placed on the outer surface of the target object and has multiple ultrasound transducers each generating a different time-dependent waveform to form a plurality of ultrasound input signals to a target probe volume within the target object. One or more sensors sense tomography output signals from the target probe volume, wherein the tomography output signals contain an interaction component generated by interaction of the probe input signals with the ultrasound input signals. A tomography analysis of the tomography output signals is performed to create a three-dimensional object map representing structural and/or functional characteristics of the target object.

A system and corresponding method are described for multi-frequency ultrasonically-encoded tomography of a target object. One or more probe inputs generate probe input signals to the target object. An ultrasound transducer array is placed on the outer surface of the target object and has multiple ultrasound transducers each generating a different time-dependent waveform to form a plurality of ultrasound input signals to a target probe volume within the target object. A photorefractive crystal mixes scattered light output signals from the target probe volume with an optical reference beam input to produce optical tomography output signals including ultrasound sum frequencies components. A photodetector senses the optical tomography output signals from the photorefractive crystal. A tomography analysis of the tomography output signals including the ultrasound sum frequencies components is performed to create a three-dimensional object map representing structural and/or functional characteristics of the target object.

A system and corresponding method are described for multi-frequency ultrasonically-encoded tomography of a target object. One or more probe inputs generate probe input signals to the target object. An ultrasound transducer array is placed on the outer surface of the target object and has multiple ultrasound transducers each operating at a different ultrasound frequency to generate ultrasound input signals to a target probe volume within the target object. A photorefractive crystal mixes scattered light output signals from the target probe volume with an optical reference beam input to produce optical tomography output signals including ultrasound sum frequencies components. A photodetector senses the optical tomography output signals from the photorefractive crystal. A tomography analysis of the tomography output signals including the ultrasound sum frequencies components is performed to create a three-dimensional object map representing structural and/or functional characteristics of the target object.

A method of bonding an RE:XAB gain medium to a heat spreader includes using a bonding solution of sodium silicate with concentration of sodium silicate is Na2O at 21.2% and SiO2 at 53% with PH>=11 mixed with nano-pure water in a 1:1 ration. Applying the bonding solution onto either a surface of the RE:XAB or a surface of the heat spreader, aligning the RE:XAB and the heat spreader, applying pressure to draw the surfaces of the RE:XAB gain medium and the heat spreader together thereby uniformly spreading the bonding solution; and then curing the bonding solution.

Systems, methods, and circuits provide passively Q-switched laser systems operable to emit a pulse train that is synchronized to a reference clock operating at a relatively high pulse repetition frequency. Such pulsed laser systems can include a gain medium; a pump source that excites the gain medium into a higher energy state; a passive Q-switch; a photodetector that produces an electronic signal synchronous with the laser output pulse; and an electronic control system that inputs the signal from the photodetector and controls the pump source to optimize the synchronization between the output laser pulses and a reference clock. The clock source may be internally generated by the electronic control system or input externally. In some examples and embodiments, passively Q-switched lasers can be utilized as transmitters in automotive LIDAR systems.

A method of bonding an RE:XAB gain medium to a heat spreader includes using a bonding solution of sodium silicate with concentration of sodium silicate is Na2O at 21.2% and SiO2 at 53% with PH>=11 mixed with nano-pure water in a 1:1 ration. Applying the bonding solution onto either a surface of the RE:XAB or a surface of the heat spreader, aligning the RE:XAB and the heat spreader, applying pressure to draw the surfaces of the RE:XAB gain medium and the heat spreader together thereby uniformly spreading the bonding solution; and then curing the bonding solution.