6 results about "Spatial dispersion" patented technology

The application provides a device and a method for fast non-destructive non-contact measurement of internal strain of silicon material, comprising: a near-infrared femtosecond laser for generating a near-infrared femtosecond laser pulse; a time-domain stretching assembly connected with the near-infrared femtosecond laser; an optical signal amplification assembly connected with the time-domain stretching assembly; a first spatial dispersion assembly arranged on an outgoing light path of the optical signal amplification assembly; a microscopic objective lens arranged on an outgoing light path of the spatial dispersion assembly; a second spatial dispersion assembly arranged on an outgoing light path of the microscopic objective lens; a high-speed photoelectric detector located on the outgoing light path of the second spatial dispersion assembly; a high-speed oscilloscope electrically connected with the high-speed photoelectric detector; and a data processing device electrically connected with the high-speed oscilloscope and used for processing and calculating an analog electric signal obtained by sampling to obtain internal strain of a sample to be measured. The application is used for solving the problems of strong dependence on speckle and low detection frame number in the prior art.

The invention provides a folding type miniaturized fiber bragg grating demodulation system, and relates to the technical field of miniature fiber bragg grating demodulation systems.The folding type miniaturized fiber bragg grating demodulation system is constructed, the optical design theory, the grating diffraction principle and the high-performance detection technology are fused, and a compact and efficient optical path structure is achieved; accurate grating parameter calculation and spatial dispersion mapping methods are utilized to ensure accurate positioning of spatial distribution of diffracted light, and the resolution and stability of wavelength demodulation are improved; by combining the comprehensive design of the diffraction limit resolution and the pixel limit resolution, parameters of an optical element and a detector are scientifically matched, and high sensitivity and high precision of the system are ensured; the optical path parameters are iteratively optimized through a simulation optimization algorithm, the imaging quality and the system stability are improved, miniaturization and integration of the optical system are achieved, and the system is more suitable for scenes such as laboratory development and teaching experiments.

The present application relates to a kind of adaptive cutting method and system based on femtosecond laser applied to the technical field of laser precision machining, method includes: the thickness parameter of the material to be cut is obtained and compared with predetermined threshold;If thickness is greater than threshold, control optical system directs laser to beisel optical system and carries out longitudinal cutting;If thickness is less than or equal to threshold, it is guided to time compression and spatial dispersion system and carries out transverse cutting.System includes femtosecond laser, longitudinal and transverse cutting optical system, beisel optical system, time compression and spatial dispersion system and controller.The present application solves the technical contradiction that single system cannot consider longitudinal cutting of thick material and transverse precision cutting of thin material by integrating two sets of optical systems and adaptive switching, realizes high-quality "one-key" processing of brittle hard material from micrometer level to centimeter level thickness.

This invention provides a rapid, non-destructive, and non-contact device and method for measuring strain on silicon surfaces, comprising: a femtosecond laser for generating femtosecond laser pulses; a time-domain stretching component disposed in the output optical path of the femtosecond laser; an optical signal amplification component disposed in the output optical path of the time-domain stretching component; a beam splitter located in the output optical path of the optical signal amplification component, for splitting the femtosecond laser pulses into a test beam and a reference beam with a specific power ratio; a spatial dispersion component disposed in the output optical path of the test beam of the beam splitter; a microscope objective disposed in the output optical path of the spatial dispersion component; a high-speed photodetector located in the output optical path of the reference beam of the beam splitter; a high-speed oscilloscope electrically connected to the high-speed photodetector; and a data processing device electrically connected to the high-speed oscilloscope. This invention addresses the problems of strong dependence on speckle and low detection frame rate in existing technologies.

The invention relates to a self-adaptive cutting method and system based on femtosecond laser applied to the technical field of laser precision machining. The method comprises the steps that the thickness parameter of a to-be-cut material is obtained and compared with a preset threshold value; if the thickness is larger than the threshold value, an optical system is controlled to guide laser to a Bessel optical system for longitudinal cutting; and if the thickness is smaller than or equal to the threshold value, guiding to a time compression and space dispersion system for transverse cutting. The system comprises a femtosecond laser, a longitudinal and transverse cutting optical system, a Bessel optical system, a time compression and space dispersion system and a controller. Two sets of optical systems are integrated and switched in a self-adaptive mode, the technical contradiction that a single system cannot give consideration to longitudinal cutting of thick materials and transverse precision cutting of thin materials is solved, and high-quality one-key type machining of brittle and hard materials with the thickness ranging from the micron level to the centimeter level is achieved.

The application provides a polarization-independent BIC metal super surface optical edge detection device and a design method, the method shows a simple and easy-to-process metal super surface, the device can realize high-quality polarization-independent two-dimensional optical edge detection with high numerical aperture and high efficiency. The design scheme provided by the method takes silicon dioxide as a substrate and C4 symmetric L-shaped aluminum metal patch as a basic unit, adjusts and controls the spatial dispersion of BIC by fine-tuning the perturbation parameters of the super surface, and realizes the polarization-independent second-order spatial differential operation. The design scheme works at a frequency of 0.6718 THz, the numerical aperture (NA) can be as high as 0.56, the peak efficiency can be as high as 36%, and the high-quality edge detection performance can be maintained. The work can realize compact, low-power and ultrafast optical edge detection, and shows great potential in various applications such as optical imaging and computer vision.