Abstract: The present invention discloses an optical path/beam splitting unit and a coaxial-wire-feed cladding head thereof. The optical path/beam splitting unit includes an adjustable mirror and at least one stage of beam splitter. Several adjustable mirrors are distributed around the beam splitter. The beam splitter splits an incident laser beam into a plurality of split beams perpendicular to the incident laser beam. The split beams all are focused to a point through the adjustable mirrors. The coaxial-wire-feed cladding head includes a cladding head mirror cavity provided therein with the optical path/beam splitting unit and a wire feeding tube. The wire feeding tube is coaxially arranged with the collimated laser beam. The wire feeding tube extends out of the cladding head mirror cavity. A wire passes through the wire feeding tube and the wire feeding nozzle in order. The adjustable mirrors adjust the focusing of the split beams onto the wire.

Abstract: A beam combiner includes: a plurality of input optical fibers, a beam combination optical fiber and an output optical fiber; the input optical fiber includes an input fiber core and an optical fiber input cladding layer wrapping an outer wall of the input fiber core, the output optical fiber includes an output fiber core and an optical fiber output cladding layer wrapping an outer wall of the output fiber core, a cross section of the optical fiber input cladding layer is fan-shaped or hexagonal and is provided with a groove and/or a protrusion along an axial direction, the plurality of input optical fibers are nested with each other to form the beam combination optical fiber, fiber cores in the beam combination optical fiber are all connected to the output fiber core, and a beam combination cladding layer of the beam combination optical fiber is connected to the output fiber core.

Abstract: The present disclosure provides a disinfecting device for a central air conditioner, which uses high-powered ultraviolet rays to efficiently and rapidly eliminate viruses, and uses two sets of parallel reflectors to reflect and overlap light curtains of the high-powered ultraviolet rays back and forth. In this way, small-sized aerosols with viruses can be eliminated, and no secondary pollutants such as ozone are produced in a process of purifying and disinfecting air by the ultraviolet rays. The entire device has a simple structure and can be used in the central air conditioner with an existing architecture. The entire device only needs to be provided in an air supply duct of the central air conditioner.

Abstract: The present disclosure provides a disinfecting device for a central air conditioner, which uses high-powered ultraviolet rays to efficiently and rapidly eliminate viruses, and uses two sets of parallel reflectors to reflect and overlap light curtains of the high-powered ultraviolet rays back and forth. In this way, small-sized aerosols with viruses can be eliminated, and no secondary pollutants such as ozone are produced in a process of purifying and disinfecting air by the ultraviolet rays. The entire device has a simple structure and can be used in the central air conditioner with an existing architecture. The entire device only needs to be provided in an air supply duct of the central air conditioner.

Abstract: Disclosed is a laser head capable of dynamically regulating a laser spot by high frequency/ultrahigh frequency micro-vibration, including a laser transmitting device, a cavity, a special electromechanical module and a shielded nozzle. The laser transmitting device is disposed at the top of the cavity. A first protective glass and a collimating lens are sequentially disposed from top to bottom within the cavity. The special electromechanical module is disposed at the bottom of the cavity and connected to the cavity by means of a housing. A focusing lens is further disposed within the housing of the special electromechanical module, and a flat spring is disposed between the focusing lens and the special electromechanical module. The special electromechanical module can cause ultrahigh frequency micro-oscillation of the focusing lens. The shielded nozzle is disposed at the bottom of the special electromechanical module.

Abstract: A beam combiner includes: a plurality of input optical fibers, a beam combination optical fiber and an output optical fiber; the input optical fiber includes an input fiber core and an optical fiber input cladding layer wrapping an outer wall of the input fiber core, the output optical fiber includes an output fiber core and an optical fiber output cladding layer wrapping an outer wall of the output fiber core, a cross section of the optical fiber input cladding layer is fan-shaped or hexagonal and is provided with a groove and/or a protrusion along an axial direction, the plurality of input optical fibers are nested with each other to form the beam combination optical fiber, fiber cores in the beam combination optical fiber are all connected to the output fiber core, and a beam combination cladding layer of the beam combination optical fiber is connected to the output fiber core.

Abstract: The present invention discloses an optical path/beam splitting unit and a coaxial-wire-feed cladding head thereof. The optical path/beam splitting unit includes an adjustable mirror and at least one stage of beam splitter. Several adjustable mirrors are distributed around the beam splitter. The beam splitter splits an incident laser beam into a plurality of split beams perpendicular to the incident laser beam. The split beams all are focused to a point through the adjustable mirrors. The coaxial-wire-feed cladding head includes a cladding head mirror cavity provided therein with the optical path/beam splitting unit and a wire feeding tube. The wire feeding tube is coaxially arranged with the collimated laser beam. The wire feeding tube extends out of the cladding head mirror cavity. A wire passes through the wire feeding tube and the wire feeding nozzle in order. The adjustable mirrors adjust the focusing of the split beams onto the wire.

Abstract: An aberration corrector and a method to reducing a spherical aberration are disclosed. The aberration corrector has a radial, rotationally symmetric variation of refractive index including a term varying in proportion to a fourth degree of a distance from the optical axis. Since the spherical aberration causes a wavefront deviation proportional to the fourth degree of distance from the optical axis, the spherical aberration can be reduced by the aberration corrector when its thickness causes the exact amount of the phase delay corresponding to the wavefront deviation, but with an opposite sign.

Abstract: An aberration corrector and a method to reducing a spherical aberration are disclosed. The aberration corrector has a radial, rotationally symmetric variation of refractive index including a term varying in proportion to a fourth degree of a distance from the optical axis. Since the spherical aberration causes a wavefront deviation proportional to the fourth degree of distance from the optical axis, the spherical aberration can be reduced by the aberration corrector when its thickness causes the exact amount of the phase delay corresponding to the wavefront deviation, but with an opposite sign.

Abstract: A modal instability of a fiber amplifier may be reduced by coupling, e.g. splicing, a length of passive multimode optical fiber to an active multimode optical fiber of the fiber amplifier. Upon launching light into the passive optical fiber, some higher order transversal modes may be excited in the passive optical fiber. The higher-order modes may interfere with the fundamental mode in the passive multimode optical fiber. However, the intermodal interference of the launched modes does not cause thermal gradients in the passive optical fiber. Upon propagation in the passive multimode optical fiber, the excited optical modes may lose mutual coherence, causing a reduction of contrast of the intermodal interference pattern along the doped core of the active optical fiber, effectively reducing modal instability in the active optical fiber.

Abstract: A beam combiner may include source elements, each configured to output a beam of light locked at a center wavelength different from center wavelengths of other source elements. The beam combiner may include a dispersive element configured to combine the beams of light into a combined beam, and a beam separator configured to separate the combined beam into an output beam and a locking beam. The beam combiner may include a spatial filter configured to prevent crosstalk within the locking beam, and to redirect the locking beam to the source elements. The dispersive element may be configured to disperse the locking beam into constituent wavelength beams. Each constituent wavelength beam may be directed to a respective one of the source elements for locking that source element at its center wavelength, and may correspond in wavelength to the center wavelength of the respective source element.

Abstract: Alignment of a multimode waveguide to a source of light or another waveguide is evaluated using a multi-wavelength light source and a modal decomposition processing of an intensity profile of a waveguide output beam, wherein inter-modal interference is averaged out over wavelength. Fitting a superposition of mode intensity profiles to a wavelength-averaged intensity profile of the output beam provides information about the modal composition of the output beam, which may be used to assess the alignment of the multimode waveguide with respect to the input light beam, and to provide a feedback for guiding a waveguide alignment process.

Abstract: A modal instability of a fiber amplifier may be reduced by coupling, e.g. splicing, a length of passive multimode optical fiber to an active multimode optical fiber of the fiber amplifier. Upon launching light into the passive optical fiber, some higher order transversal modes may be excited in the passive optical fiber. The higher-order modes may interfere with the fundamental mode in the passive multimode optical fiber. However, the intermodal interference of the launched modes does not cause thermal gradients in the passive optical fiber. Upon propagation in the passive multimode optical fiber, the excited optical modes may lose mutual coherence, causing a reduction of contrast of the intermodal interference pattern along the doped core of the active optical fiber, effectively reducing modal instability in the active optical fiber.

Abstract: A beam combiner may include source elements, each configured to output a beam of light locked at a center wavelength different from center wavelengths of other source elements. The beam combiner may include a dispersive element configured to combine the beams of light into a combined beam, and a beam separator configured to separate the combined beam into an output beam and a locking beam. The beam combiner may include a spatial filter configured to prevent crosstalk within the locking beam, and to redirect the locking beam to the source elements. The dispersive element may be configured to disperse the locking beam into constituent wavelength beams. Each constituent wavelength beam may be directed to a respective one of the source elements for locking that source element at its center wavelength, and may correspond in wavelength to the center wavelength of the respective source element.

Abstract: An aberration corrector and a method to reducing a spherical aberration are disclosed. The aberration corrector has a radial, rotationally symmetric variation of refractive index including a term varying in proportion to a fourth degree of a distance from the optical axis. Since the spherical aberration causes a wavefront deviation proportional to the fourth degree of distance from the optical axis, the spherical aberration can be reduced by the aberration corrector when its thickness causes the exact amount of the phase delay corresponding to the wavefront deviation, but with an opposite sign.

Abstract: An aberration corrector and a method to reducing a spherical aberration are disclosed. The aberration corrector has a radial, rotationally symmetric variation of refractive index including a term varying in proportion to a fourth degree of a distance from the optical axis. Since the spherical aberration causes a wavefront deviation proportional to the fourth degree of distance from the optical axis, the spherical aberration can be reduced by the aberration corrector when its thickness causes the exact amount of the phase delay corresponding to the wavefront deviation, but with an opposite sign.

Abstract: Alignment of a multimode waveguide to a source of light or another waveguide is evaluated using a multi-wavelength light source and a modal decomposition processing of an intensity profile of a waveguide output beam, wherein inter-modal interference is averaged out over wavelength. Fitting a superposition of mode intensity profiles to a wavelength-averaged intensity profile of the output beam provides information about the modal composition of the output beam, which may be used to assess the alignment of the multimode waveguide with respect to the input light beam, and to provide a feedback for guiding a waveguide alignment process.