42results about How to "Small spot diameter" patented technology

An information recording medium, comprising: a recording layer which can phase-change reversibly between a crystal phase and an amorphous phase by using an optical means or an electric means, wherein the recording layer comprises at least Ge, Te, M1 (which is at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Yb and Lu), M2 (which is at least one element selected from the group consisting of Sb and Bi) and M3 (which is at least one element selected from the group consisting of Te and Bi).

The invention discloses an LED-excited short wavelength infrared fluorescent microscopic imaging system. In the system, laser light emitted by a single-color LED passes through a collimating lens to be collimated firstly and is introduced into a light path of a microscope vertical illumination device, the exciting light is reflected with a dichroic beam combiner and converges onto a back focal plane of a microscopic objective, converging light forms parallel exciting light beams after passing through the objective and illuminates onto a sample, and a fluorescence probe in the sample is excitedto emit fluorescence; and a fluorescence signal passes through the objective, penetrates through the dichroic beam combiner and is finally received by a detection surface of an InGaAs camera to realize photoelectric conversion, and the signal is transmitted to a computer for data processing to obtain an imaged picture or a video. The LED-excited short wavelength infrared fluorescent microscopic imaging system has the remarkable advantages of high signal-to-noise ratio, high magnification, high resolution, capability of real-time imaging, capability of tomography, large penetration depth, small tissue damage and the like.

Provided are a high-precision selective laser sintering method and device for an ultraviolet point light source. An ultraviolet laser is adopted, a printing model is generated through a computer, and signals are output through control software, thus movement of a scanning galvanometer is controlled, the point light source is formed by laser in a forming cylinder, and powder sintering forming is carried out. The device comprises a preheating system and a powder laying device, the preheating system and the powder laying device are connected with the computer, and the computer is connected with the ultraviolet laser and the scanning galvanometer. The method and device have the advantages that the light spot diameter is small, the heat affected area is small, single photon energy is large, the processing precision is high, the forming quality is good, the processing material range is wide, and the like.

The invention relates to the technical field of a self-adaptive optical system, and in particular to a sodium guide star laser atmospheric link compensation system. The system comprises a first laserbeam expanding system, a second laser beam expanding system, a dichroic mirror, a deformation mirror, a beam combining and expanding system, a wavefront detection and control system, a reflecting mirror and a calibration light source. According to the system, another laser different from the sodium laser wave length and the sodium laser combining beam are emitted in common-caliber and are converged on an atmospheric layer of a sodium laser transmission path to generate atmospheric back scattering; the atmospheric turbulence distortion is measured and compensated by using a back-scattering image; when the sodium laser emits, the phase distortion opposite to the atmospheric turbulence is carried and counteracted when the laser passes through the atmospheric turbulence so that the sodium laser has flat wavefront distributions, smaller light spot diameter and higher energy density when reaching the sodium layer for convergence, thereby being beneficial to reducing the measurement error ofthe self-adaptive optical system of the ground-based optical telescope and improving the imaging correction effect.

The invention relates to a marking method and a marking device. The marking device is used for removing anodic aluminum oxide on a product. The marking device comprises a laser, a fixed seat, a beam expander, a galvanometer and a focusing lens; the laser is used for generating a laser beam; the fixed seat is provided with a through hole; the beam expander is arranged on the fixed seat, is opposite to the laser, and is used for enlarging the diameter of the laser beam; the galvanometer is arranged on the fixed seat, and is close to the beam expander; the galvanometer is used for deflecting the laser beam output by the beam expander, so as to allow the laser beam to pass the through hole; and the focusing lens is arranged on the fixed seat, is located on one side, departing from the galvanometer, of the fixed seat, and corresponds to the through hole. According to the marking method and the marking device, the laser beam generated by the laser is subjected to combined action of the beam expander and the focusing lens, and then the power density of the laser beam acting on the surface of the product is increased substantially, so that a situation that no product after being marked generates stress deformation is ensured, and the product has good conductivity.

A thermally assisted magnetic head includes a main magnetic pole layer, a near-field light generating layer having a generating end part generating near-field light arranged within a medium-opposing surface, and an optical waveguide guiding light to the near-field light generating layer. The thermally assisted magnetic head includes a base layer which a base groove part having a width gradually getting smaller along a depth direction and extending in an intersecting direction intersecting with the medium-opposing surface is formed. The near-field light generating layer has an in-groove generating layer formed inside of the base groove part. The in-groove generating layer is formed along an inner wall surface of the base groove part and has a thin-film like structure.

The invention belongs to the field of sensors, and aims to effectively reduce the diameter of a light spot and improve the timing resolution of an optical fiber type tip timing sensor. According to the technical scheme adopted in the invention, an optical fiber bundle type tip timing sensor based on a self-focusing lens is characterized in that a plurality of multi-mode optical fibers closely surround one single-mode optical fiber to form an optical fiber bundle; the self-focusing lens is assembled at the front end of the optical fiber bundle; the single-mode optical fiber is connected with alaser and a photoelectric receiver through a circulator; the multi-mode optical fibers are only connected with the photoelectric receiver; laser light emitted by the laser is projected onto the end face of a blade through the single-mode optical fiber and the self-focusing lens; and laser light reflected by the end face of the blade passes through the self-focusing lens, and is projected onto thephotoelectric receiver through the single-mode optical fiber and the multi-mode optical fibers. The optical fiber bundle type tip timing sensor is mainly applied to the design and manufacturing occasions of optical fiber sensors.

In order to provide an electron gun capable of maintaining a small spot diameter of a beam converged on a sample even when a probe current applied to the sample is increased, a magnetic field generation source 301 is provided with respect to an electron gun including: an electron source 101; an extraction electrode 102 configured to extract electrons from the electron source 101; an acceleration electrode 103 configured to accelerate the electrons extracted from the electron source 101; and a first coil 104 and a first magnetic path 201 having an opening on an electron source side, the first coil 104 and the first magnetic path 201 forming a control lens configured to converge an electron beam emitted from the acceleration electrode 103. The magnetic field generation source is provided for canceling a magnetic field, at an installation position of the electron source 101, generated by the first coil 104 and the first magnetic path 201.

The invention discloses a femtosecond laser processing device. In the laser optical path direction, a femtosecond laser device, a horizontal optical path device, a vertical optical path device, a laser processing device and a processing platform are sequentially included. The diameter of light spots of a laser is reduced through utilization of the femtosecond laser device. A probe is arranged in the horizontal optical path device, and a mini-type camera is arranged in the laser processing device, so that the states of a laser beam and a sample are observed in real time. A first reflector, a second reflector, a third reflector, a fourth reflector and a fifth reflector are arranged in the horizontal optical path device so that devices, located among the reflectors, in the horizontal optical path device can be reasonably arranged, and the structure of the processing device is more compact. Sliding platforms in the X direction, the Y direction and the Z direction are arranged on the processing platform so that the processing platform can be moved and adjusted in the processing process.

The invention relates to the field of laser technologies, nonlinear optical physical technologies, quantum optics technologies and quantum communication technologies, in particular to a compact singlecrystal thin cavity and an entangled photon source system using the same. The free spectral path range (FSR) and the line width delta v of the compact single crystal thin cavity satisfy the followingformulae as shown in the description. The compact single crystal thin cavity adopts a very thin nonlinear crystal single-cavity structure, and has the advantages of being small in size and easy to control; the proper cavity length l and coating parameters are selected, wherein the coating parameters are used for adjusting the transmittance T; and by only satisfying the formula (2), the required photonic line width can be freely designed. Moreover, due to the resonance effect of the compact single crystal thin cavity, the spectral brightness of generated photons is greatly enhanced relative tothe spectral brightness during single pass; the surface is subjected to theoretical calculation; and an enhancement factor of the spectral brightness of photon pairs generated by the compact single crystal thin cavity relative to the spectral brightness during the single pass is in direct proportion to the square (F<2>) of the fineness of the compact single crystal thin cavity.