11 results about "Photoelasticity" patented technology

This invention provides a method and apparatus for photoelastic stress reconstruction based on physically constrained deep learning, relating to the fields of experimental mechanics and optical mechanics. The method involves acquiring images of the interference fringe state of a transparent specimen under load to obtain multi-channel tensor input data; using a physically enhanced convolutional neural network model for feature extraction and processing, and performing differential calculations to obtain full-field stress component output data; visualizing and rendering the full-field stress component output data to obtain reconstructed visual data; comparing the full-field stress component output data with reference benchmark data, calculating error indices, and recording process time to obtain accuracy and efficiency evaluation data; and simultaneously integrating and displaying the reconstructed visual data and the accuracy and efficiency evaluation data to obtain a comprehensive evaluation and reconstruction result. This invention solves the inherent limitations of traditional phase unwrapping and stress separation techniques.

An object of the present application is to provide a phase difference film capable of producing an image display device in which unevenness in mounting is suppressed, and a polarizing plate and an image display device using the phase difference film. The phase difference film of the present application is a phase difference film having a support exhibiting a reverse wavelength dispersion in an in-plane retardation, and a liquid crystal layer directly laminated on the support, wherein the support is a polymer film subjected to a stretching treatment in at least one direction in the plane, the liquid crystal layer is a positive C-plate obtained by fixing the orientation state of a liquid crystal composition containing a liquid crystal compound, and the photoelastic constant of the support is 30 x 10 ‑12 or less.

This invention belongs to the field of quality inspection technology. It provides a deep learning-based quality inspection system for wine bottle caps and boxes, comprising: using photoelastic polarization to detect residual stress in the wine bottle body, introducing the material stress optical constant, determining the residual stress damage coefficient, and quantifying the stress damage degree of the wine bottle body; if the stress damage degree of the wine bottle body is low, conducting simulated transportation vibration tests on the corresponding packaging boxes of the same batch of wine bottles, collecting real-time vibration data of the wine boxes, and assessing the structural failure risk of the wine boxes; if the structural failure risk of the box body is low, constructing a dynamic stress transfer model of the cap and box based on the simulated transportation vibration test results, and determining the temporal dynamic stress of the bottle body; this invention fills the gap in traditional testing methods that neglect secondary dynamic stress damage to the bottle body during transportation, providing precise data support for packaging vibration resistance optimization, transportation condition calibration, and lightweight design.

Provided are: a thermoplastic resin having sufficiently high optical properties and excellent physical properties such as excellent photoelastic coefficient and saturated water absorption; and an optical lens or the like containing such a thermoplastic resin.　The problem is solved by a thermoplastic resin containing a structural unit (A) derived from a bifunctional compound represented by general formula (1). In general formula (1), W represents a phenyl group or a cyclohexyl group, and n represents 0 or 1.

The application relates to the technical field of industrial vision detection, in particular to a chain belt screw production process control method and system based on industrial vision. The method comprises the following steps: performing online detection, acquiring a first image and a second image, and performing spatial alignment on the first image and the second image; performing pixel-level information supplement on a highlight area in the first image according to the brightness information of the two images; identifying an optical artifact area according to the difference between the two in a plastic chain belt area, and marking the optical artifact area as a non-detection area through first processing; then performing defect feature analysis on a screw body area in the processed image except the non-detection area, extracting defect features, comparing the defect features with preset standards, and outputting a control signal according to a comparison result. The method solves the problems that in the prior art, when a chain belt screw is detected online, the high light reflection on the surface of a metal screw hides defect details, and the photoelastic effect of a translucent plastic chain belt produces optical artifacts to interfere with defect identification.

The present application relates to a kind of achromatic RGB photoelasticity measurement methods based on color polarized camera, which is based on plane polarized light path implementation, in plane polarized light path, first light source and second light source of vertical distribution are sequentially through polarizer, half mirror, the tested piece and the color polarized camera of polarization array assembly respectively, birefringence effect is generated by stress at the tested piece, and photoelastic image with polarization information is collected by color polarized camera;Photoelastic image is generated by RGB channel synthesis algorithm to generate an achromatic photoelastic dark-field image;Based on photoelastic dark-field image, in combination with the calibration curve of RGB color value-equal difference line fringe number, equal difference line phase is solved;Based on the collected photoelastic image, equal inclination line phase is calculated using four-step phase shift method.Compared with the existing instantaneous photoelasticity method of circular polarized light path, the present application improves the precision and efficiency of color photoelasticity measurement and other advantages.

This utility model discloses a weak pressure measuring device, including a measuring bracket, a photoelastic sensing layer, a black placement box, a light source, a camera, and a computer. The photoelastic sensing layer is composed of two photoelastic material films orthogonally stacked and fixed to the measuring bracket. The black placement box is placed on the photoelastic sensing layer. The light source is positioned directly below the photoelastic sensing layer and is used to emit light onto it. The camera is positioned directly above the photoelastic sensing layer and is used to capture images of the deformation of the photoelastic sensing layer. The camera is connected to the computer via a data cable. By stacking the two photoelastic material films orthogonally along their optical axes to form the sensing layer, the birefringence effect is enhanced, producing clear, high-contrast interference fringes and color changes under weak pressure, greatly improving the measurement sensitivity and visualization effect.

This invention discloses a photoelastic stress measurement system and method based on a polarization grating. The stress measurement system, along the optical path, includes a light source, a polarizer, a photoelastic sample to be measured, and a polarization grating. The light emitted from the light source is converted into linearly polarized light by the polarizer. The transmitted portion passes through the photoelastic sample, where the light vector is split into two components along the two principal stress directions. The polarization grating ensures that the diffraction distribution of the incident linearly polarized light is only at the ±1st and 0th orders. Since the photoelastic model has birefringence, the linearly polarized beam exiting the photoelastic model is diffracted to the ±1st and 0th orders under the action of the polarization grating. The vast majority of the beam is circularly polarized at the ±1st order, while a very small portion, with the same polarization state as the incident beam, is distributed at the 0th order. This invention solves the problems of traditional photoelastic stress measurement methods, such as complex equipment, inaccurate measurement results, and the inseparability of phase delay and the angle of the principal stress directions in the photoelastic model.

This invention relates to the field of optical thin film inspection technology, specifically disclosing a method and system for inspecting skylight display thin films. The method includes: applying a frequency-converting electric field under controllable humidity partial voltage modulation, simultaneously acquiring picosecond photoelastic imaging data to construct a dielectric relaxation-photoelastic coupling field, identifying interface debonding precursors and encoding them as a subcritical defect entropy state matrix; using the spatial coordinates of this matrix as the focusing point to excite a multi-physics field phase-locked coherent superposition signal, reconstructing a three-band energy dissipation topology network, identifying topological defect nodes and registering them with the entropy state matrix to generate a failure prediction map; fusing the coupling field and the topology network to establish a service limit extrapolation model based on the self-organized criticality of dissipative structures, generating a personalized adaptive compensation strategy, and encapsulating it into a quality adaptive digital twin that can be embedded in the thin film. This invention achieves a leap from post-event verification to pre-event prediction, providing a new paradigm for the reliability assessment of intelligent display dimming films.

The application discloses a boundary-weighted photoelastic model internal stress separation method and a system thereof, and the method comprises the following steps: collecting model isoclinal line parameters and isochromatic line parameters; calculating a full-field principal stress, and specifying a calculation path direction and a solution region; performing boundary identification and data preprocessing; calculating a full-field shear stress, performing average pooling on the full-field shear stress; judging whether abnormal values and pixelated random errors are effectively eliminated, and whether gradient information in original data is reserved in the preprocessed data; performing boundary initial normal stress calculation; determining internal normal stress in one direction; calculating internal normal stress in another direction; respectively smoothing the internal normal stress in the two directions to obtain final full-field normal stress distribution. The application fully considers abnormal values and pixelated random errors in collected data, and the method proposed by setting a reasonable threshold and a correction method can effectively avoid the influence of collection errors on full-field stress solution.

Systems and methods for visualization of nerves are disclosed. A tissue region is illuminated with short-wave infrared (SWIR) light and reflected light is captured to form images in which nerve substructures, including bands of Fontana, are resolved. In some embodiments, nerve contrast is enhanced by dynamic polarization modulation, achieved by rotating polarizing elements or by electronically altering illumination polarization using liquid-crystal or photoelastic devices. A polarization-resolving camera may detect polarization-dependent reflectance, enabling extraction of periodic modulation unique to birefringent nerve tissue. The disclosed techniques improve nerve visibility relative to conventional imaging and may be used for surgical navigation, robotic surgery safety, or other in vivo applications.