Method for measuring absorption rates of cavities on basis of substitution process and efficiency of detectors

Abstract

The invention discloses a method for measuring absorption rates of cavities on the basis of a substitution process and the efficiency of detectors, and belongs to the field of optical radiation measurement. The method has the advantages that the standard uncertainty of the method is superior to 0.001%, and the method not only is applicable to measuring the absorption rates of the cavities with high absorption rates, but also is applicable to measuring the absorption rates of the common cavities; the measured absorption rates of the cavities with sloping bottoms are 0.999928+ / -0.000005; laser light is divided into measurement light beams and reference light beams by a partially-transparent and partially-reflecting mirror in measurement procedures, the stability of the laser light is monitored by a reference light path, signal voltages are measured, and ratios of the signal voltages of a signal light path to the signal voltages of the reference light path are defined as the efficiency of the detector; change trend of random errors due to drifting of the laser light has similar effects on the measurement light path and the reference light path, so that the random errors can be reduced by the aid of each ratio of two corresponding signals; the absorption rates of the cavities are measured by the aid of the efficiency of the detectors, accordingly, the standard uncertainty can be improved, and the absorption rates of the cavities with the high absorption rates can be measured.

Description

technical field [0001] The invention belongs to the field of optical radiation measurement, and in particular relates to a method for measuring the absorptivity of a cavity with high absorptivity through detector efficiency based on a substitution method. Background technique [0002] In order to establish a higher-precision on-board calibration radiometer, in view of the development trend of ground calibration and standard transfer routes, we proposed the project of developing the Absolute Radiance Calibration Primary Radiometer (ARCPR) in orbit. ARCPR is an electrical substitution radiometer working in a low temperature environment (20K), including a Total Solar Irradiation cavity (Total Solar Irradiation, TSI) and a High Response cavity (High Response, HS). Absorption rate is an important parameter in the calculation process of optical power. The TSI cavity is required to have an ultra-high absorptivity above 0.9999, and the measurement uncertainty of its absorptivity is ...

AI Technical Summary

Problems solved by technology

Commonly used measurement methods for absorptivity include substitution method and interchange method, but the random error caused by laser drift and other reasons increases the uncertainty of the measurement results, and the uncertainty is greater than 0.001%, which cannot meet the measurement of high absorptivity cavities need

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