Design of scattering sampling attenuation unit for detector array target

The detector array target is a common equipment for measuring the spatial and temporal distribution of laser intensity. In order to achieve high-precision measurement of target laser parameters, the sampling attenuation method is its key point. Aiming at scattering sampling attenuation technology for detector array target, based on the bidirectional transmission distribution function, the transmission and scattering characteristics of ground glass and other materials were studied. And the calculation formula of the laser intensity attenuation magnification which was scattered to the photosensitive surface of the detector was deduced. The scattering sampling attenuation unit combined with ground glass and engineering diffuser was designed. Combined with the ABg scattering model, the simulation model of scattering sampling attenuation materials were established by TracePro software. The results show that the designed sampling attenuation structure is able to withstand the power density of 2 000 W/cm² laser irradiation for 20 s; within the scattering emission angle of ±5.44°, the sampling unevenness of the detection surface is about 3.34%; the attenuation magnification simulation design result and experimental measurement error is about 0.805%. The scattering sampling attenuation method has the advantages of strong resistance to laser damage, better spot homogenization effect, quantitative attenuation of laser intensity and broad spectral response. This manner has a good application prospect.