Fig. 1. Schematic diagrams of preparation of high temperature photocathodes. (a) Mono-evaporation technique; (b) co-evaporation preparation technique

Fig. 2. Performance comparison for high temperature PMTs prepared by two different techniques. (a) Quantum efficiency; (b) cathode integral sensitivity

Fig. 3. Energy resolution and quantum efficiency uniformity for high temperature PMTs prepared by two different techniques. (a) Energy resolution curves; quantum efficiency uniformity comparison of (b) mono-evaporation and (c) co-evaporation preparation techniques

Fig. 4. Plateau characteristic curves for high temperature PMTs prepared by two different techniques

Fig. 5. Comparison of spectral response curves for high temperature PMTs prepared by two different techniques

Fig. 6. Comparison of high and low temperature curves for high temperature PMTs prepared by two different techniques

Fig. 7. Thickness comparison at three different positions in light window of high temperature photocathode window. (a) Mono-evaporation preparation technique; (b) co-evaporation preparation technique

Fig. 8. Surface morphology comparison at center and edge of high temperature photocathode window. (a)(b) Mono-evaporation preparation technique; (c)(d) co-evaporation preparation technique

Fig. 9. Test results of high temperature PMTs in practical applications. (a) Energy resolution varying with temperature for high temperature PMTs from NNVT and similar products abroad; (b) plateau characteristic comparison at 25 ℃ and 175 ℃ for high temperature PMTs from NNVT and similar products abroad