10 results about "Bidirectional reflectance distribution function" patented technology

A neural process prediction method for surface reflection characteristics based on micro-surface model guidance is proposed. Current BRDF representations based on analytical models or deterministic neural networks perform poorly in complex material modeling and sparse sampling scenarios. There is a lack of standardized and accurate probabilistic prediction methods for tasks related to quantifying prediction uncertainty and analyzing and controlling error propagation. This invention forms an initial model by training a network on a completed BRDF dataset and applying physical guidance constraints. Based on the initial model, a probabilistic model of the bidirectional reflection distribution function is formed to create a family of BRDF function probability distribution models. The prediction process for reflection characteristics in unobserved directions is then completed based on the established family of BRDF function probability distribution models.

This invention discloses an angle-resolved measurement device for spectral polarization-dependent reflection (SVBRDF) of a material surface, belonging to the field of SVBRDF measurement technology. It includes: a light source module, a rotating rocker arm, a three-dimensional moving platform, a spatially fixed detector module, a hollow rotating motor, a bottom rotating motor, a sample holder motor, a plane mirror, and a rocker arm support. The three-dimensional moving platform is mounted on the bottom rotating motor, and the sample holder motor is mounted on the three-dimensional moving platform. The sample is fixed on the sample holder motor and rotates around its own center. The plane mirror is embedded in the rotating rocker arm, which is mounted on the hollow rotating motor, forming a spatial reflection characteristic measurement module for different regions of the material surface. The three-dimensional moving platform changes different regions of the sample surface as measurement targets. The bottom rotating motor changes the zenith angle of the incident light, and the sample holder motor changes the azimuth angle of the incident light.

A filter with backscattering characteristics, wherein the filter has a linear transmittance of 60% or more for at least a portion of wavelengths in the wavelength range of 760 nm to 2000 nm. The bidirectional reflectance distribution function (BRDF) is defined as follows: BRDF(0°; 20°, -60°) is defined for the direction where the polar angle of the incident light's incident direction is 0° and the azimuth angle formed with the incident surface is 20° and the polar angle is -60°. Similarly, BRDF(30°; 20°, -60°) is defined for the direction where the polar angle of the incident light's incident direction is 30° and the azimuth angle formed with the incident surface is 20° and the polar angle is -60°. The value of the bidirectional reflectivity distribution function in the direction where the polar angle of the incident direction is 60°, the azimuth angle formed with the incident surface is 20°, and the polar angle is -60° is BRDF(60°; 20°, -60°), and when the incident light is light with at least a portion of the wavelengths within the visible light wavelength range, |BRDF(0°; 20°, -60°)-BRDF(30°; 20°, -60°)| / BRDF(0°; 20°, -60°) is 1.0 or less, and |BRDF(0°; 20°, -60°)-BRDF(60°; 20°, -60°)| / BRDF(0°; 20°, -60°) is 1.0 or less.

The present application relates to the technical field of laser transmission characteristic test, and more particularly to a kind of middle wave infrared laser long-distance transmission attenuation characteristic field test method and device.The method is indirect measurement method, by building diffuse reflection board at specified position of transmission path, laser arriving on diffuse reflection board is quantitatively measured using detector, combined with bidirectional reflection distribution function of diffuse reflection board, the power to target after long-distance atmospheric transmission of laser is obtained, by comparing with the laser output power of emission end, the long-distance transmission power attenuation characteristic of laser can be obtained, solve the current laser atmospheric transmission attenuation characteristic measurement, laser radar has no middle wave infrared measurement method, and the problem that direct measurement cannot be measured by detector directly receiving after long-distance transmission spot size is too large, cannot be measured by detector directly receiving the power of specified position of transmission path.The measuring device structure is simple, and the long-distance transmission power attenuation characteristic of middle wave infrared laser can be indirectly measured.

This invention belongs to the field of Earth science and remote sensing technology, and discloses a method and system for identifying lithium-bearing minerals in deeply incised terrain. The method utilizes UAVs to acquire hyperspectral imagery and LiDAR topographic data; calculates the true solar-sensor observation geometric parameters of the deeply incised surface; designs a terrain shadow reflectance recovery model (TSRR) to recover reflectance in shadowed areas, and constructs a multi-parameter atmospheric correction lookup table (LUT) based on model 6S; constructs a radiative transfer-bidirectional reflectance distribution function (DIT-BRDF) model to correct for surface angle variations in deeply incised areas, and obtains the corrected spectral and spatial information; and constructs a lithium-bearing mineral identification model (SST) to automatically identify spodumene, lepidolite, lithiometrazine, and phosphogypsum. This invention significantly improves the accuracy and efficiency of remote sensing detection of lithium deposits under complex terrain conditions, providing a new technical approach for the rapid identification and quantitative assessment of lithium deposits in deeply incised areas.

Optical sensors (e.g., cameras) and (e.g., IR) illumination sources may be distributed in an environment (e.g., an interior space such as a cabin or cockpit of an ego-machine) and synchronized to generate frames of sensor data. By positioning the optical sensors and assigning them corresponding frequency ranges, the resulting sensor data (e.g., images from different perspectives and with different illumination patterns) may be used to extract reflectance data, the reflectance data may be used to generate more accurate sensor data (e.g., HDR images, images re-rendered using an extracted bidirectional reflectance distribution function), and the resulting sensor data may be used in one or more downstream tasks, such as operator or occupant monitoring or detection tasks (e.g., gaze detection, pose detection, attentiveness or fatigue assessment, facial recognition, gesture recognition, occupant presence detection, child presence detection, seat belt detection, hands-on-wheel detection, etc.), generating visualizations (e.g., video conference calls), and / or otherwise.

This invention relates to the field of industrial automation measurement, and discloses a point spectral intelligent controller and its measurement method. The controller includes a communication interface module, a data acquisition and synchronization module, a storage module, and a data processing module. The method includes: S1, constructing an original measurement vector matrix containing distance information and multi-band light intensity information; S2, performing adaptive filtering on the original measurement vector matrix; S3, extracting the surface normal vector and calculating the spatial tilt angle; S4, performing inverse rotation correction of geometric height and bidirectional reflectance distribution function compensation of spectral intensity; S5, calculating the flatness index and outputting the measurement results. This invention uses an FPGA to construct a parallel I / O controller and global synchronization trigger logic in the data acquisition and synchronization module, combined with a direct memory access transmission mechanism, thereby enabling nanosecond-level synchronous exposure of all measurement points and achieving high-speed throughput of large-scale matrix data, effectively eliminating time distortion during dynamic measurement.