On-Line Measurement for Cs-O Layer Thickness of NEA Photocathode

A method of on-line thickness measurement for Cs-O for NEA photocathode is suggested. The structure of the evaluation system of Negative Electron Affinity photocathode is introduced. The change of the spectral response of NEA photo-cathode is tested during the process of manufacturing the NEA photo-cathode, the responding curves are obtained, the optimum thickness of Cs-O for NEA photocathode is achieved. At last the conclusion is given according to the experiment results.