Noise in cathodoluminescence light

A theory is given of the noise in cathodoluminescence light and the results are compared with experiments on Sylvania 5BNP16 and RCA5WP11 cathode-ray tubes. The measurements indicate that the noise in cathodoluminescence is mainly caused by the shot noise of the primary beam. The noise intensity is proportional to the magnitude of the voltage applied to the tube for voltages above 10 kV. The spectral distribution of the noise corresponds to the square of the frequency response of the cathode-ray tube screen as expected theoretically. The application to light amplifiers is discussed.