Energy spectral response of photocathode for soft X-ray streak camera

Based on the analysis of production process of the photoelectron of the streak camera photocathode during the photoemission, the formula of photocathode energy spectral response was obtained in the region of 0.1-10 keV. The effects of photocathode parameters on spectral response were discussed. Based on the model, energy spectral response curves of Au photocathode and CsI photocathode were obtained and analyzed. And the reliability of the formula was validated by the calibrated data. The results indicate that the best thicknesses of CsI and Au photocathodes are 60 nm and 10 nm. The energy spectral response of CsI is 1 to 2 orders higher than that of Au.