4 results about "Optical absorption coefficient" patented technology

The invention belongs to the field of biomedical photonics, photoacoustic imaging and deep learning, and provides an optical absorption coefficient resolving system and method based on photoacoustic imaging and a non-training network, and the method comprises the steps: taking physically-driven Monte Carlo simulation as an optical forward model, and embedding the optical forward model into a neural network frame which does not need to be trained in advance, direct and high-precision inversion from a single initial sound pressure distribution image to optical absorption coefficient distribution is realized through a self-constraint resolving process.

Provided is an optical absorption coefficient calculation technique capable of calculating an optical absorption coefficient of any part of an object at high speed. An optical absorption coefficient calculation device A includes a global coordinate transform operator determination unit 3 that determines a global coordinate transform operator for transforming a specific coordinate in a specific region into a global coordinate value, a rotational transform operator determination unit 4 that determines a rotational transform operator for transforming the global coordinate value into a coordinate after relative rotation, a detector coordinate value determination unit 5 that determines a detector coordinate value based on a coordinate acquired by applying the global coordinate transform operator and the rotational transform operator to the specific coordinate, a convolution operation unit 6 that performs convolution operation with a filter function on transmission projection data, and an integration unit 7 that calculates the optical absorption coefficient of the specific coordinate by acquiring a calculated value of the convolution operation calculated based on the transmission projection data of the detector coordinate value for each rotation angle and accumulating the calculated value.

The present application belongs to the technical field of deep learning, and particularly relates to a two-stage blind image defogging method based on priori guiding diffusion, aiming at solving the distortion problem of traditional defogging methods in complex scenes. The method comprises constructing a two-stage blind image defogging model, which comprises a first stage and a second stage. The first stage is based on an improved atmospheric scattering model for physical modeling, and the improved atmospheric scattering model is an enhanced atmospheric scattering model with the introduction of an optical absorption coefficient. The first stage outputs a transmission map, a haze-free reference image and an atmospheric light parameter. The second stage is based on a diffusion model for generation optimization. The transmission map, the haze-free reference image and the atmospheric light parameter output by the first stage are used as physical priors to be integrated into the generation process of the diffusion model for image defogging. In the second stage, an adaptive difference fusion convolution is set, a fog domain multi-source fusion attention mechanism is set, and a pixel-level and wavelet domain dual-effect color correction strategy is adopted.

A system for in-situ monitoring of optical element health in a laser apparatus comprises direct measurement of optical element temperature and recording a history of variations of the optical element temperature during successive periods of irradiation and non-irradiation. The direct measurement may be achieved by a thermocouple inserted into the laser system and pace di contact with the optical element. The history of temperature variations may be used to calculate as trajectory of the change in optical absorption coefficient, which may be used to predict the remaining lifetime of the optical element and schedule service event.