Design considerations and detection capability verification of an imaging Thomson scattering system based on an IEMCCD

摘要

An imaging Thomson scattering system has been designed and built to perform the spatial-resolution-oriented plasma electron temperature and density measurements, which incorporates a second generation image intensifier and an EMCCD as a detection system. In general, the characteristic of weak scattering of radiation is the most concern in Thomson scattering systems. Therefore, it's quite essential for the initial system design to avoid further loss of the amount of radiant power transferred from the source to the detector, and to perform the detection capability verification based on the designed setup. This paper will focus on three points. Firstly, The key design parameters including magnification and f number of the collection lens, the diameter and NA of the fiber, the entrance and exit slit area and f number of the spectrometer are designed interactively to maximize light throughput, with also beam quality taken into account. Then, the system setup is described and the expected photon number per pulse per scattering length is calculated. Finally, from the comparison between the measured radiation photons of a standard lamp and the calculated photons based on the designed condition, with both spatial binning and EM gain performed, the capability of the detection system is verified.