Abstract: An intracavity frequency doubling fiber laser includes pump sources, optical beam combiners and a bidirectional optical amplifier; a first fiber collimator, a first optical polarization rotating device, a polarizer, a laser frequency doubling device and a laser cavity mirror being arranged on one side of the bidirectional optical amplifier along an optical path in sequence; a second fiber collimator, a polarization beam splitting device, a second optical polarization rotating device and a reflection device being arranged on the other side of the bidirectional optical amplifier along the optical path in sequence; the disclosure has small size and low cost, which can output different wavebands of frequency-doubled lasers by replacing components.

Abstract: A testing control method and apparatus for an application, and an electronic device and a storage medium are provided. The method includes: acquiring, in response to an automated testing request for a target application, semantic segmentation maps of a current access page and at least two consecutive historical access pages associated with the current access page, and a historical operation type and a historical operation location map that correspond to each consecutive historical access page; inputting the semantic segmentation maps, the historical operation type, and the historical operation location map into a pre-trained behavior prediction model, and acquiring a target operation type and a target operation location probability map on the current access page that are predicted by the pre-trained behavior prediction model; and controlling a testing of the current access page of the target application based on the target operation type and operation location probability map.

Abstract: A high extinction-ratio rotator includes a collimator that can collimate a signal light from an optical fiber, a pair of polarizing splitting prisms that include a first birefringence crystal wedge and a second birefringent crystal wedge, that can separate two orthogonal polarization components of the signal light into a vertically polarized light and a horizontally polarized light, a non-reciprocal 45-degree polarization rotator which the vertically polarized light and the horizontally polarized light exiting the pair of polarizing splitting prisms pass through, and a reflector. The vertically polarized light and the horizontally polarized light exiting the non-reciprocal 45-degree polarization rotator intersect on a surface of the reflector and are reflected back into the non-reciprocal 45-degree polarization rotator.

Abstract: A laser oscillation amplifier includes a seed laser that can produce an input laser beam, a pumping source that can produce a pump light, a semiconductor laser shaping device that can receive the pump light and to produce a shaped pump light, a beam combiner that can combine the shaped pump light and the input laser beam, and a gain fiber coupled with the beam combiner. The gain fiber can absorb the pump light and amplifying the input laser beam to produce an output laser beam.

Abstract: A semiconductor laser shaping device includes, along the light path of a semiconductor laser, a fast axis collimating lens, slow axis collimating lens, the half wave plate, a polarization beam combining prism, and a crawling prism group. The laser emitted by the semiconductor laser is collimated by a fast-axis collimating lens and then by a slow-axis collimating lens, and subsequently injected into a half wave plate and polarization beam combining prism, which compresses its spot size along the slow axis while keeping the spot size unchanged along the fast axis. The laser beam then passes through the crawling prism group, which shifts a portion of the light in the slow-axis direction to the fast-axis direction, which again compresses the light beam in the slow-axis direction. The device can reduce the beam size of a semiconductor laser in the slow-axis direction, reducing its beam parameter product and improving beam quality.

Abstract: A semiconductor laser shaping device includes, along the light path of a semiconductor laser, a fast axis collimating lens, slow axis collimating lens, the half wave plate, a polarization beam combining prism, and a crawling prism group. The laser emitted by the semiconductor laser is collimated by a fast-axis collimating lens and then by a slow-axis collimating lens, and subsequently injected into a half wave plate and polarization beam combining prism, which compresses its spot size along the slow axis while keeping the spot size unchanged along the fast axis. The laser beam then passes through the crawling prism group, which shifts a portion of the light in the slow-axis direction to the fast-axis direction, which again compresses the light beam in the slow-axis direction. The device can reduce the beam size of a semiconductor laser in the slow-axis direction, reducing its beam parameter product and improving beam quality.

Abstract: A method for making a microchip laser includes preparing a laser-cavity chip assembly comprising a gain media, a first substantially flat surface, and a second substantially flat surface parallel to the first substantially flat surface. The method also includes forming a first reflective film on the first substantially flat surface to form a first cavity mirror, forming a second reflective film on the second substantially flat surface to form a second cavity mirror, and patterning at least one of the first reflective film or the second reflective film by removing at least a portion of the reflective film in the outer portion to form a center reflective portion in the one of the first reflective film or the second reflective film. The first cavity mirror and the second cavity mirror can suppress higher order transverse modes and produce a single TEM00 mode in the lasing light.

Abstract: A method for making a microchip laser includes preparing a laser-cavity chip assembly comprising a gain media, a first substantially flat surface, and a second substantially flat surface parallel to the first substantially flat surface. The method also includes forming a first reflective film on the first substantially flat surface to form a first cavity mirror, forming a second reflective film on the second substantially flat surface to form a second cavity mirror, and patterning at least one of the first reflective film or the second reflective film by removing at least a portion of the reflective film in the outer portion to form a center reflective portion in the one of the first reflective film or the second reflective film. The first cavity mirror and the second cavity mirror can suppress higher order transverse modes and produce a single TEM00 mode in the lasing light.