28 results about "Speckle contrast" patented technology

A speckle contrast optical spectroscopy techniques for measuring cerebral blood metrics such as cerebral blood flow and / or cerebral blood volume at multiple regions of the brain using one or more light sources and detectors of a plurality of channels disposed on a headset worn by a subject and detecting a brain injury or other brain malfunction by comparing cerebral blood metrics measurement at different regions.

This invention discloses a laser dimension measurement device and method for hollow plastic panels, belonging to the field of laser measurement technology. The method obtains the optical signal-to-noise coefficient based on laser echo intensity, surface reflection uniformity, and speckle contrast; it obtains the motion disturbance coefficient based on encoder slip rate, dynamic bow height of the panel, and edge burr fluctuation frequency; and it obtains the medium interference coefficient based on ambient stray light flicker frequency, transmission depth offset, and color saturation. Furthermore, based on the optical signal-to-noise coefficient and motion disturbance coefficient, combined with the resonant frequency of the internal cavity of the panel and the hollow layer collapse coefficient, a resonance-collapse measurability model is used to obtain resonance-collapse measurability. Finally, combining the medium interference coefficient and the current scanning axis acceleration, an optimized scanning axis acceleration is obtained through an acceleration optimization model. This invention can comprehensively evaluate multi-source interference during the measurement process, dynamically optimize scanning parameters, and improve measurement accuracy and stability.

The imaging apparatus configured to assess and quantify motion associated with an object and, in a specific case of an eye—retinal vascular anatomy and hemodynamics and generate substantially contrast-free maps of retinal blood flow over a wide field-of-view at up to 590 fps and under short exposure durations (>50 μs), is applicable for diagnosis, study, and management of neurodegenerative conditions (i.e. mild cognitive impairment and Alzheimer's disease) and systemic cardiovascular diseases (i.e. athero- and arteriosclerosis, coronary artery occlusion, and hypertension). The apparatus employs a) a set of apertures substantially blocking light, delivered from a source of light to an illumination arm of the apparatus, from impinging onto an axial point of the front surface of the lens of the illumination arm, and b) polarization gating between the illumination and light-collecting arms of the apparatus. In one implementation, the apparatus is configured to allow for irradiation of the object with an optical field a degree of coherence and / or spectral content of which are varied delivered through the same optical train including the set of apertures.

The application discloses a laser speckle blood flow imaging method and system, and the method comprises the following steps: acquiring a laser speckle image sequence to be processed; processing the laser speckle image sequence to be processed by using a non-overlapping window space contrast algorithm to obtain a low-resolution space contrast image in a logarithmic domain to be processed; inputting the low-resolution space contrast image in the logarithmic domain to be processed into a pre-trained image super-resolution model to obtain a predicted high-resolution speckle contrast image in the logarithmic domain; and calculating a laser speckle blood flow image according to the predicted high-resolution speckle contrast image in the logarithmic domain. The application adopts a lightweight image super-resolution network to improve the spatial resolution, is easy to process in real time, and is easy to realize laser speckle blood flow imaging.

A method of image enhancement of a reflectance confocal microscope is disclosed. The method comprises: receiving by a processor a first image captured by a detector of the confocal microscope, at a first position of a pinhole; receiving one or more second images captured by the detector, at at least one second position of the pinhole; and adding, by the processor, the one or more second images to the first image to reduce a speckle contrast in the combined image. In addition, the first position of the pinhole is a confocal position, and the at least one second position is a shifted position with respect to the confocal position.

This application provides a method, device, system, and medium for monitoring blood perfusion. The method includes: acquiring a speckle image sequence of the tissue region to be monitored based on a laser emitted to it; acquiring ambient light information corresponding to the speckle image sequence and motion information between adjacent speckle images in the speckle image sequence; performing anti-interference processing on the speckle image sequence based on the ambient light information and the motion information between adjacent speckle images to obtain a corrected speckle image sequence; calculating the spatiotemporal joint speckle contrast of the corrected speckle image sequence to obtain a spatiotemporal joint speckle contrast; determining the blood perfusion parameters of the tissue region to be monitored based on the spatiotemporal joint speckle contrast using a pre-established mapping model between speckle contrast and blood perfusion parameters; and outputting a warning message when the blood perfusion parameters meet preset warning conditions. This method aims to improve the accuracy of blood perfusion monitoring.

The present invention provides an optical measuring apparatus and optical measuring method that can improve the degree of freedom in imaging conditions of the surface to be measured for speckle contrast or sparkle contrast. [Solution] The optical measuring device 1 comprises an optical system 3 that images the light emitted from the surface to be measured 7 of a light-emitting electronic display or light-emitting surface to be measured for speckle contrast or sparkle contrast; a two-dimensional sensor array 4 having a two-dimensional sensor array surface 41 on which the emitted light is imaged and which images the emitted light; and a calculation unit 6 that calculates speckle contrast or sparkle contrast based on the emitted light imaged under imaging conditions in which the size of the light-emitting region on the surface to be measured that contributes to the imaging of the diffraction-limited spot of the emitted light on the two-dimensional sensor array surface is constant. The size of the light-emitting region is determined based on the size of the diffraction-limited spot and the magnification of the optical system, which is determined from the focal length of the optical system and the imaging distance from the surface to be measured to the optical system.

The invention discloses a projection system and a display control method thereof, by arranging a phase light modulator in the projection system, the effects of shaping and homogenizing light are achieved, the effects of a diffusion element, a lens group and the like in an illumination light path can be replaced, the light path design is simplified, and the size of an optical engine is optimized. After the phase light modulator is partitioned according to the distribution of incident light combination light spots, the phase needing to be loaded can be independently determined for each partition, pertinence is better achieved, for laser of the same wavelength, the phase light modulator is divided into a plurality of partitions to conduct phase modulation, and the phase modulation efficiency is improved. When the modulated laser enters the display element, the effect of overlapping a plurality of light spots is achieved, the uniformity of a light field is better improved, and the speckle problem is solved. The optical extensions of the three-color laser after partition modulation of the phase light modulator are roughly the same, the utilization rate of the three-color laser is improved, the speckle contrast ratio is reduced, the chromaticity uniformity of a projected image is improved, and the display effect is optimized.

The invention discloses an intraoperative parathyroid gland recognition and blood supply monitoring method and system based on a laser speckle contrast technology, relates to the technical field of intraoperative parathyroid gland recognition, and solves the problems that in the prior art, parathyroid gland recognition is difficult, the intraoperative mistaken cutting risk is high, and blood flow detection is insufficient. The method comprises the following steps: acquiring an autofluorescence image and a speckle contrast image, carrying out noise reduction and image enhancement processing on the autofluorescence image, and evaluating the blood vessel distribution and blood flow velocity of the identified parathyroid gland according to the speckle contrast of the speckle contrast image, according to the autofluorescence image and the speckle contrast image, the position and the form of the parathyroid gland are manually recognized, the autofluorescence image and the speckle contrast image are input into a pre-trained neural network model to obtain an AI recognition result, and by combining LSCI, NIRAF and AI technologies, real-time recognition and blood supply state monitoring of the parathyroid gland are achieved. And objective blood supply state evaluation and automatic parathyroid gland identification can be provided by using the neural network model.

The application relates to a laser projection device and a laser projection system. A depolarizer component is additionally arranged on a laser display light path between a light source and a light modulation component, so that birefringence and interference effects occur in the depolarizer component, and polarized light is converted into random polarized light. Birefringence caused by lens stress in the light modulation component usually has a fixed fast and slow axis direction, which can affect the polarization state of light passing through the lens. In the embodiments provided by the application, the depolarizer component can rotate around the light beam propagation direction in the working state. When the light beam passes through the lens each time, the polarization direction of the light changes relative to the axis of the stress birefringence. The phase delay caused by the stress has different effects in different directions, and the effects are offset after time averaging, so that the negative influence of the birefringence effect caused by the lens stress on the depolarization effect of the depolarizer component can be reduced, and the speckle contrast can be greatly reduced, and the speckle suppression effect is improved.

The invention discloses a roadbed transverse and longitudinal slope laser ruler real-time detection and three-dimensional curve presentation method, and relates to the technical field of roadbed optical measurement, and the method comprises the steps: carrying out the local contrast value statistics of a laser speckle image sequence, and generating a laser speckle contrast spectrum; performing phase calculation and point cloud construction on the laser interference ranging phase signal to obtain a laser interference ranging phase residual error; performing spatial correlation and weight statistics on the laser speckle contrast spectrum and the laser interference ranging phase residual, and outputting a roadbed quality state diagram; performing superposition fusion on the roadbed quality state diagram and the three-dimensional point cloud data, and outputting a roadbed enhanced three-dimensional data set; and performing elevation curved surface reconstruction on the roadbed enhanced three-dimensional data set, and performing transverse and longitudinal slope feature line extraction and graphical rendering to complete presentation of a roadbed transverse and longitudinal slope three-dimensional curve. According to the invention, through double-mechanism cooperation of the laser speckle contrast spectrum and the laser interference ranging phase residual, integrated evaluation of the surface and inner quality of the roadbed and accurate presentation of the three-dimensional morphology are realized.

Embodiments of the present application provide a kind of laser speckle contrast image correction method, device and system, it is related to image processing technical field.The method includes: obtaining multiple speckle images;According to each speckle image, determine light intensity distribution diagram;Determine the original speckle contrast image of target speckle image;According to light intensity distribution diagram, determine local light intensity variation coefficient diagram, wherein each pixel point in local light intensity variation coefficient diagram is used to indicate the variation coefficient of pixel intensity in the neighborhood of pixel point in light intensity distribution diagram;According to the value of each pixel point in local light intensity variation coefficient diagram, the value of pixel point in corresponding position in original speckle contrast image is corrected, to obtain corrected speckle contrast image and output.Selecting the present application, can reduce the influence of uneven illumination on laser speckle image, so that blood flow image luminance is uniform and contrast is accurate, to improve the accuracy of blood flow velocity estimation.

The invention provides a method for testing dynamic speckles displayed by laser. The method comprises the following steps of: a) acquiring multiple frames of laser speckle images of an area to be detected by using an imaging device; b) calculating the average space speckle contrast ratio and the average time speckle contrast ratio of the area to be detected according to the multiple frames of laser speckle images; c) collecting the average static space speckle contrast ratio of the test system, and calculating system coherence parameters according to the average static space speckle contrast ratio; step d), according to the formula, calculating to obtain a dynamic component proportionality coefficient of the to-be-measured area; and e) according to the mixed scattering model formula, calculating to obtain the dynamic speckle index of the to-be-measured area.

This invention provides a method, apparatus, and system for correcting laser speckle contrast images, relating to the field of image processing technology. The method includes: acquiring multiple speckle images; determining a light intensity distribution map based on each speckle image; determining an original speckle contrast image of the target speckle image; determining a local light intensity variation coefficient map based on the light intensity distribution map, wherein each pixel in the local light intensity variation coefficient map represents the variation coefficient of pixel intensity in the neighborhood of the pixel in the light intensity distribution map; correcting the values ​​of corresponding pixels in the original speckle contrast image based on the values ​​of each pixel in the local light intensity variation coefficient map, obtaining and outputting a corrected speckle contrast image. Using this application can reduce the influence of uneven illumination on laser speckle images, resulting in more uniform brightness and accurate contrast in blood flow images, thereby improving the accuracy of blood flow velocity estimation.

The application provides a radial artery compressor control method and related equipment, which can be used in the field of image processing technology; the method comprises the following steps: acquiring a first laser blood image of a hand region of a target object collected by an image acquisition component; determining a target speckle contrast according to the pixel intensity of a pixel point in the first laser blood image, and determining the current blood flow rate of the hand region according to the target speckle contrast; in the case that the current blood flow rate indicates that the radial artery has an occlusion risk, controlling the ulnar artery balloon to deflate, and determining a target pressure according to the highest pressure pulse wave amplitude of the target object in the deflation process of the ulnar artery balloon; controlling the ulnar artery balloon to inflate until the pressure applied by the ulnar artery balloon to the ulnar artery reaches a blockage pressure, and controlling the radial artery balloon to inflate or deflate until the pressure applied by the radial artery balloon to the radial artery reaches the target pressure. In the application, the blood flow of the radial artery is ensured to be unobstructed to avoid radial artery occlusion.

The invention discloses a tongue picture texture analysis and phlegm-dampness constitution recognition method and device based on multispectral imaging and a storable medium, and belongs to the technical field of traditional Chinese medicine tongue diagnosis objectification and artificial intelligence application. In order to solve the problem of lack of objective and standardized quantitative analysis of tongue picture analysis at present, the device defines a tongue coating viscoelasticity index and a sublingual microcirculation response index by collecting a lingual surface multispectral image, tongue coating deformation recovery sequence data and sublingual speckle contrast sequence data; thick and greasy tongue coating, sticky and unsmooth tongue coating, phlegm-dampness blocking, qi and blood blocking and the like in traditional Chinese medicine are converted into quantitative indexes, classification and recognition are carried out on the phlegm-dampness constitution according to an AI recognition model, and results are output. According to the device, by fusing multispectral biological imaging and artificial intelligence analysis technologies, the conventional tongue diagnosis process depending on experience is objectively quantified, the physiological mechanism behind phlegm-dampness discrimination is disclosed, and the consistency and credibility of diagnosis results are improved.

The invention relates to a method of imaging by displaying variations in speckle contrast, which makes it possible to reveal more reliably the movements of parts of a scattering object (100) to be analyzed. The method comprises the use of a reference object (101) to verify that the illuminating laser source used does not undergo operational fluctuations during the execution of the method. The use of a reference object also makes it possible to know the maximum speckle contrast that the illuminating laser source is capable of producing. The method can also continue by constructing speckle contrast variation images by subtracting each contrast value calculated for the object to be analyzed from the average speckle contrast value calculated for the reference object. Thus, speckle contrast variation images constructed during repetitions of the method separated in time, using different laser sources, in particular with different spectral bandwidths, different imaging optics and different image sensors, can be effectively compared with one another. To this end, each speckle contrast image of the object to be analyzed is corrected by the specific contribution of the illuminating laser source and optionally also by another contribution caused by the image detection noise.

The invention is suitable for the technical field of computer vision, and provides a time self-correlation imaging method and system based on an adaptive orientation space window. The speckle contrast imaging and self-correlation imaging method comprises the following steps: acquiring continuous multi-frame speckle images; the method comprises the following steps: presetting a basic space window by taking a target pixel as a center, and giving a plurality of orientations; selecting a certain frame of speckle image, respectively extracting speckle light intensity sequences of corresponding orientations in the basic space window, and calculating the spatial domain variance of the light intensity sequence of each orientation; selecting the orientation with the maximum light intensity variance, and determining the orientation as an effective calculation window of the target pixel; and performing time autocorrelation function calculation based on the effective calculation window so as to solve a blood flow velocity parameter of the target pixel. According to the method, the noise of the blood flow area can be reduced, and the real-time monitoring requirement is met while the high spatial resolution is guaranteed.

The present invention relates to a device (100), systems (500, 500′, 500″) and a method for providing imaging of one or more aspects of blood perfusion induced by cardiac induced blood motion in a skin region (12) of a subject. Current perfusion imaging systems use either photoplethysmography (PPG) or speckle contrast (SC), but a problem of both techniques is that considerable ambiguity exists because the source of the signal (volume pulsatility in PPG or blood flow in SC) is unknown. The present invention is based on the idea of combining two different types of measurement, namely widefield imaging and radial imaging, in order to estimate the source depth (20) of the signal to provide more accurate PPG imaging and SC imaging.

The application provides a kind of microscopic imaging method and probe device based on laser illumination, belong to microscopic imaging technical field, the present application is generated laser by semiconductor laser and is conducted to lens system by optical fiber and forms transmission type illumination, utilizes rotation diffusion sheet and carries out speckle time domain average processing to reduce speckle contrast to threshold value below, adopts pulsed laser stroboscopic illumination mode to eliminate motion blur, by telecentric lens and industrial camera collection through the groove in the particle image, with high density particle adhesion segmentation processing based on graph cut accurately separates adhesion particle from high solid content image and extracts particle shape parameter and particle size distribution data, finally by laser power self-adaptive regulation and control artificial intelligence model, according to image quality evaluation function, realize illumination power closed loop control, solve the technical problem that particle adhesion segmentation precision is seriously reduced under high solid content scene caused by laser speckle noise.

An infinite impulse response filter includes at least one N x N multimode optical coupler and one or more mode scrambling loops. The at least one N x N multimode optical coupler has N input ports and N output ports. One of the N input ports is coupled to a laser source that generates a light beam. The at least one N x N multimode optical coupler splits the light beam into a plurality of sub-beams that are partitioned in an amplitude domain across the N output ports. One of the N output ports is coupled to a detection system. The one or more mode scrambling loops include a mode scrambler and couple one of the N output ports to one of the N input ports. The one or more mode scrambling loops produce temporal incoherence and spatial incoherence that reduce peak power and speckle contrast of the light beam.

This invention discloses an adaptively enhanced laser speckle contrast blood flow imaging method. It utilizes a laser speckle contrast imaging system to probe the surface of the tissue under test and acquires a sequence of original speckle images using a CMOS camera. An initial speckle contrast image is calculated based on the original speckle image sequence. The initial speckle contrast image is then segmented to obtain a segmented image. An adaptively enhanced speckle contrast image is calculated based on the original speckle image sequence and the segmented image. The laser speckle contrast blood flow imaging method provided by this invention can improve the imaging effect of blood vessel edges and microvessels, making the contrast image of blood vessels clearer and reflecting more details. In imaging deeper blood vessels, it can improve the visualization effect of blood vessels, with higher noise attenuation and better imaging quality.

An imaging system for viability assessment of a tissue of a living subject includes a light source for emitting a beam of light; a light delivery member coupled to the light source for delivering the beam of light onto a tissue surface of the living subject to illuminate the tissue surface; a light collection member configured to collect light from the illuminated tissue surface responsive to the illumination; a detector coupled to the collection member for acquiring images of the light from the illuminated tissue surface; and a controller arranged to operate the detector to acquire the images of the light from the illuminated tissue surface, receive the acquired images from the detector, and process the acquired images t for the intraoperative assessment of tissue viability.

A method for improving a lithographic process of imaging a portion of a design layout onto a substrate using a lithographic apparatus. The method includes computing a multi-variable cost function that is a function of: (i) a plurality of design variables that affect characteristics of the lithographic process and (ii) a radiation bandwidth of a radiation source of the lithographic apparatus; and reconfiguring one or more of the characteristics (e.g., EPE, image contrast, resist, etc.) of the lithographic process by adjusting one or more of the design variables (e.g., source, mask layout, bandwidth, etc.) until a termination condition is satisfied. The termination condition includes a speckle characteristic (e.g., a speckle contrast) maintained within a speckle specification associated with the radiation source and also maintaining an image contrast associated with the lithographic process within a desired range. The speckle characteristic being a function of the radiation bandwidth.

A combined auto-fluorescence imaging and laser speckle contrast imaging (LSCI) system to enable intra-operative parathyroid identification and viability assessment with the same tool. The system includes a light source for emitting a beam of light to illuminate a target of interest, and an imaging head positioned over the target of interest for individually acquiring auto-fluorescence images and LSCI images of light from the illuminated target of interest responsive to the illumination. Auto-fluorescence imaging helps identify the parathyroid, while LSCI helps assess its viability.

Laser-Speckle Contrast imaging apparatus configured to assess and quantify motion associated with an object and, in a specific case of an eye—retinal vascular anatomy and hemodynamics and generate substantially contrast-free maps of retinal blood flow over a wide field-of-view at up to 590 fps and under short exposure durations (>50 μs), is applicable for diagnosis, study, and management of neurodegenerative conditions (i.e. mild cognitive impairment and Alzheimer's disease) and systemic cardiovascular diseases (i.e. athero- and arteriosclerosis, coronary artery occlusion, and hypertension). The apparatus employs a) a set of apertures substantially blocking light, delivered from a source of light to an illumination arm of the apparatus, from impinging onto an axial point of the front surface of the lens of the illumination arm, and b) polarization gating between the illumination and light-collecting arms of the apparatus. In one implementation, the apparatus is configured to allow for irradiation of the object with an optical field a degree of coherence and / or spectral content of which are varied delivered through the same optical train including the set of apertures.

The utility model discloses a speckle-eliminating dodging device applied to a multimode fiber, which relates to the technical field of laser application and comprises a shell, an input flange plate, an output flange plate, a vibration component and a fiber extrusion component, the input flange plate and the output flange plate are respectively and fixedly arranged at two ends of the shell, the vibration component is fixedly arranged at the bottom of the shell, and the fiber extrusion component is fixedly arranged at the bottom of the shell. The optical fiber extrusion assemblies are connected with the shell in a sliding fit mode, the two optical fiber extrusion assemblies are the first extrusion assembly and the second extrusion assembly respectively, and the first extrusion assembly and the second extrusion assembly are arranged on the two sides of the vibration assembly respectively. Through the synergistic effect of vibration and stretching, speckles of an output light field are greatly reduced, the uniformity of the light field is improved, the speckle contrast ratio is remarkably reduced, and application scenes with high requirements for the quality of the light field can be effectively met. The vibration assembly and the optical fiber extrusion assembly are integrated in the limited shell, the structure is compact, a small space is utilized to achieve the function to the maximum extent, and miniaturization and integration of the device are facilitated.

Methods and systems for laser speckle contrast imaging with motion correction and motion compensation are disclosed. The method includes exposing a target region to coherent first light of a first wavelength, the target region including living tissue, and capturing at least one image sequence including first speckle images, and determining one or more transformation parameters of an image registration algorithm for registering the first speckle images to each other. The transformation parameters can be based on a similarity measure of pixel values of a group of pixels in a plurality of images of the at least one image sequence, the images in the plurality of images being selected from or associated with the first speckle images.