A laser comprising a laser cavity formed by a first optical reflector, a gain region, a second optical reflector having a plurality of reflection peaks, and at least one optically active region. The first mirror may be a DBR or comb mirror and the second mirror may be a comb mirror. The spectral reflectance of the second optical reflector is adjusted at least partially based on an electric signal received form the optically active region such that only one reflection peak is aligned with a cavity mode formed by the first and second reflector.

A lithium niobate (LN) external cavity includes a Vernier mirror structure which includes two or more microresonators where: one or more or all of the Vernier microresonators are tuned by the electro-optic Pockels effect of LN, with tuning electrodes integrated with the resonators, and one of the Vernier microresonators could be tuned by the thermo-optic effect, with a local heater integrated with the resonator. One or more or all of the Vernier microresonators include a section or the whole resonator that is periodically poled to achieve quasi-phase matching for nonlinear frequency conversion directly inside the laser cavity. The lithium niobate (LN) external cavity also includes a phase shifter whose phase is tuned by the electro-optic Pockels effect of LN. A Sagnac loop mirror is placed at the end of the device to function as the output end mirror of the laser cavity.

A beam positioner for deflecting a beam path, along which a diffracted beam of linearly polarized laser light is propagatable, within a two-dimensional scan field, the beam positioner includes a first acousto-optic deflectors (AOD) to deflect the beam path within a first one-dimensional scan field extending along a first axis of the two-dimensional scan field, a second AOD to deflect the beam path within a second one-dimensional scan field extending along a second axis of the two-dimensional scan field, a phase retarder arranged between the first AOD and the second AOD and within the beam path along which the beam of laser light is propagatable from the first AOD and a mirror arranged between the first AOD and the second AOD and within the beam path along which the beam of laser light is propagatable from the first AOD.

A beam positioner for deflecting a beam path, along which a diffracted beam of linearly polarized laser light is propagatable, within a two-dimensional scan field, the beam positioner includes a first acousto-optic deflectors (AOD) to deflect the beam path within a first one-dimensional scan field extending along a first axis of the two-dimensional scan field, a second AOD to deflect the beam path within a second one-dimensional scan field extending along a second axis of the two-dimensional scan field, a phase retarder arranged between the first AOD and the second AOD and within the beam path along which the beam of laser light is propagatable from the first AOD and a mirror arranged between the first AOD and the second AOD and within the beam path along which the beam of laser light is propagatable from the first AOD.