13 results about "High spatial frequency" patented technology

A glass article is provided that includes: a glass substrate comprising a thickness and a primary surface; and a textured region defined by the primary surface. The textured region comprises a low spatial frequency region and a high spatial frequency region substantially superimposed within the low spatial frequency region. Further, the low spatial frequency region comprises an average lateral feature size that exceeds an average lateral feature size of the high spatial frequency region. In addition, the textured region comprises a surface roughness (Ra) from about 10 nm to about 1000 nm.

A method for generating an earth model is disclosed. The method includes receiving input data. The input data includes an initial earth model and observed seismic data. The method also includes determining a high spatial frequency component and a low spatial frequency component based on the input data. The method further includes preparing a full bandwidth model based on the high spatial frequency component and the low spatial frequency component. The method also includes generating synthetic seismic data using the full bandwidth model. The method also includes generating the earth model based on the synthetic seismic data and the observed seismic data.

A virtual reality head-mounted display device and a method for myopia control by stimulating small cell pathways are disclosed, relating to the fields of virtual reality (VR) technology and visual health intervention technology. The device includes: a display; a memory storing a computer program; and a processor coupled to the display and the memory for executing the computer program to control the display to present visual stimuli. The visual stimuli are configured to present dynamic patterns with first color-opposites characteristics within at least a portion of the visual field to selectively activate small cell pathways in the user's visual system. The intervention time of the dynamic patterns ranges from 3 to 30 minutes, and the time frequency ranges from 5 to 10 Hz. Through high spatial frequency (≥2 cpd) radial targets with red-green opposition, the device selectively stimulates retinal small cell ganglion cells and subsequent small cell visual nerve conduction pathways, significantly increasing the choroidal thickness near the fovea, thereby inhibiting myopia progression.

Various methods and systems are provided for selective recombination of reconstructed nuclear medicine (NM) image regions. The method may include acquiring and sorting imaging scan data that includes data elements having different accuracy properties into two or more different groups using an anticipated accuracy metric, reconstructing a first initial image volume from a first group having a highest anticipated accuracy metric of the two or more different groups, reconstructing a second initial image volume from a combined data group comprising data of the first group and a second group of the two or more different groups, wherein the second group has a lower anticipated accuracy metric compared to the first group, and generating an optimized image volume using corresponding image values from the first initial image volume, the second initial image volume, and an output of a high spatial frequencies detection (HSFD) operator applied to the first initial image volume.

To appropriately execute a CI method by increasing a change from a base image even when an image with a strong visual feature such as a face image of a specific individual is used as the base image.SOLUTION: The disclosed method is a method of generating a CI from a base image by a classificationimage (hereinafter referred to as "CI") method, and includes performing, on a first face image, preprocessing of removing a high spatial frequency component of an image by a spatial filter to obtain a second face image obtained by removing the high spatial frequency component of the first face image, and using the second face image as the base image to obtain the CI by the CI method.SELECTED DRAWING: Figure 1

An optical lens for augmented visual perception of a scene, the optical lens comprising a bandpass filter or a blurring filter, so as to lower contrast and high spatial frequencies of the scene. Also, methods for improving visual perception and treating an impairment of the magnocellular and / or parvocellular visual pathway with this optical lens. Also, a method for selecting optical lenses for improving visual perception of a scene.

The invention discloses an intermediate infrared star light interference fringe generation and aberration suppression evaluation system and method based on 4F system spatial filtering. The system is applied to coherent interference measurement of mid-infrared band fixed star light in astronomical observation. The system comprises a telescope collimation unit, an aberration equivalent unit, a 4F relay light path unit, an adjustable pinhole spatial filtering unit arranged on a 4F middle focal plane, a reference light generation and phase tilt modulation unit and a coherent superposition and interferogram output unit. By arranging the pinhole, the wavefront high-spatial-frequency component of the test arm is cut, so that the influence of atmospheric turbulence or high-order aberration on interference fringes is reduced, and the regularity of the fringes is improved. The system further provides a parameterization strategy for setting the pinhole size with the Airy spot radius as a scale, and interference fringes under different pinhole multiplying power can be subjected to comparative analysis and wavefront diagram PV value calculation. The method is suitable for the scenes of intermediate infrared coherent imaging, wavefront shaping, spatial filtering teaching demonstration and the like.

The invention belongs to the information security related fields of identity authentication, anti-counterfeiting, encryption, random number generation and the like, and particularly relates to an ultra-low authentication error rate Hash authentication method based on an optical physical unclonable function (PUF), which comprises the following steps of: obtaining a binary coded image taking zero as a threshold value by using resampling and a DoG filtering method based on two-dimensional speckles generated by the optical PUF; the internal correlation of a binary coded image is reduced through a method of combining image pixels and removing image edge pixels, so that the randomness of a hash key is improved; through adjustment of filtering kernel parameters, low spatial frequency components and high spatial frequency components of speckles collected under different environment noise and shot noise conditions are adaptively filtered. According to the invention, while the randomness of the excitation-response characteristics of the optical PUF is ensured, the authentication error rate can be reduced, and the authentication reliability is enhanced.

The invention belongs to the technical field of biomedical engineering, and particularly relates to a skin image collecting and processing method and an optical instrument system.The method comprises the steps that a feature image of a skin area irradiated by structured light is obtained; wherein the feature image comprises a plurality of low-spatial-frequency images and high-spatial-frequency images with different phases; calculating an absorption coefficient and a reduced scattering coefficient of a skin area in the feature image as corresponding optical features; calculating a height modulation phase difference and / or a width modulation phase difference of the skin area in the feature image as a corresponding contour feature; and generating a quasi-projection pattern for phototherapy according to the optical features and the contour features of the skin area. According to the invention, the skin of the patient is irradiated by the structured light and the corresponding feature image is collected, so that the optical features and the contour features of the skin tissue in the image are extracted to define the diseased area, and objective, high-sensitivity and automatic chronic skin disease diagnosis and optical treatment are realized.

The invention relates to a solar temperature measuring device for an outdoor cable and a monitoring system thereof, and relates to the technical field of temperature measuring equipment, the device is configured to receive Raman backscattering light obtained by inputting pulsed light into an optical fiber cable and measure temperature distribution in the length direction of the optical fiber cable, and the device comprises a first filtering mechanism, a second filtering mechanism and a third filtering mechanism, and the first filtering mechanism is used for receiving and filtering the measurement signal. A second measurement signal processed by a filter or a first measurement signal not processed by the filter is selected and synthesized according to measurement signals of intensity distribution or temperature distribution of Raman backscattered light in the length direction of the optical fiber cable. And a corresponding threshold value is set along the length direction of the optical fiber cable according to the change of the amount of noise overlapped with the measurement signal. Therefore, under the condition that the waveform of the signal component is not reduced, the noise component with high spatial frequency is effectively reduced, and the temperature resolution can be improved.

An apparatus for characterizing a light source has an aperture having a light-transmitting area defining a light path from the light source and a field of view at a first image plane and a diffraction grating forming a light pattern having at least two diffraction orders of light from the light source. An image sensing system has an image sensor array of pixels to provide image data from the light pattern and a control logic processor. The image sensing system identifies and reports angular direction of the light source, based on the position of the diffraction orders in the light pattern and a diffraction signature of the light source, having high spatial frequency intensity oscillations within at least one non-zero diffraction order. Features sensed by the pixel array are smaller than the light-transmitting area of the aperture. The diffraction signature exhibits light emission peak and light source spectral characteristics.

The application provides a guided quantum visual image recognition method and device, the method comprising: designing a guided paradigm based on a visual high-low frequency complementary mechanism; constructing an enhanced quantum-classical hybrid model based on the guided paradigm for quantum image recognition. The enhanced quantum-classical hybrid model comprises: an early visual cortex module for extracting low spatial frequency (LSF) information of an input image; an orbitofrontal cortex module for generating an initial prediction based on the LSF information and locating a potential high spatial frequency (HSF) region based on an attention mechanism; a ventral visual pathway module for identifying the HSF region based on a high-frequency complexity index of two-dimensional discrete Fourier transform; and a fusiform gyrus module for combining the HSF region obtained by the orbitofrontal cortex module and the ventral visual pathway module and identifying high spatial frequency (HSF) information by using a quantum re-uploading circuit. The application can improve the efficiency and accuracy of image classification.

The invention discloses a fluorescence microscopic image enhancement method based on spatial frequency domain modulation, which comprises the following steps of: starting from a physical imaging model, constructing a low-pass filter and a band-pass filter according to physical parameters of a fluorescence microscope by utilizing the difference of out-of-focus information and in-focus information in a fluorescence microscopic image of a sample to be detected in a spatial frequency domain; according to the method, low-spatial-frequency distribution information is attenuated, high-spatial-frequency distribution information is enhanced, shot noise with higher frequency is filtered out, so that a fluorescence microscopic image with the signal-to-noise ratio and the resolution ratio comprehensively enhanced is obtained, hardware does not need to be modified, and the method can be universally used for a wide-field fluorescence microscope and a confocal scanning fluorescence microscope.