Relative radiometric calibration method for tdi scanning imaging system adapting to multi-channel bidirectional output

Abstract

The invention belongs to the technical field of relative radiation calibration, and in particular relates to a relative radiation calibration method for a TDI scanning imaging system adapting to multi-channel bidirectional output. The method includes recording the maximum radiance, recording luminance data at intervals, calculating multi-channel average radiation response data, linearly segmenting the collection points, performing two-point relative radiation calibration correction for each segment, and recording the average gray value of the first and last images of each segment. Steps such as typical values ​​of radiance, selection of corresponding relative radiation calibration coefficients, etc. Compared with the prior art, the present invention solves the problem of relative radiation calibration of a multi-channel TDI scanning imaging system, not only can control the relative radiation calibration accuracy in a single channel, but also can correct the relative radiation calibration accuracy between channels.

Description

technical field [0001] The invention belongs to the technical field of relative radiation calibration, and in particular relates to a relative radiation calibration method for a TDI scanning imaging system adapting to multi-channel bidirectional output. Background technique [0002] At present, the military and civilian aspects of optical remote sensing imaging systems are increasingly required to have the ability to acquire large-scale wide, high signal-to-noise ratio target images. In order to obtain large wide, high signal-to-noise ratio target images, TDI scanning imaging is usually used. The TDI scanning imaging system mainly includes an optical system and a photodetector device. On the one hand, there is vignetting in the optical system, that is, the uniform target is transformed by the optical system to redistribute the energy, resulting in the concentration of energy at the center of the focal plane and gradually decreasing to the edge, resulting in The energy distri...

AI Technical Summary

Problems solved by technology

The TDI scanning imaging system mainly includes an optical system and a photodetector device. On the one hand, there is vignetting in the optical system, that is, the uniform target is transformed by the optical system to redistribute the energy, resulting in the concentration of energy at the center of the focal plane and gradually decreasing to the edge, resulting in The energy distribution on the focal plane is uneven; on the other hand, due to the intrinsic characteristics of the material, the response characteristics of each detection pixel to the same energy input are different, resulting in uneven response; secondly, the data transfer rate of the TDI device is high, and the device often uses The multi-channel output structure meets the high-frequency data transfer, and the image produces channel block effect due to different channel signals passing through different paths and different operational amplifiers.

The inconsistency caused by the combined effects of these three factors will cause strong pattern noise in the acquired image, seriously affecting the imaging quality, and is an important and key factor restricting the multi-channel TDI scanning imaging system.

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