Streak cameras for soft X-ray and optical radiation

The principal component of a streak camera is the image converter tube. A slit shaped photocathode transforms the radiation into a proportional emission of electrons. An electron-optics arrangement accelerates the electrons and projects them into a phosphor screen creating the image of the slit. A pair of deflection plates deflects the electronic beam along a direction perpendicular to the main dimension of the slit. Different portions of the phosphor screen show the instantaneous image of the slit with brightness proportional to the number of emitted electrons and, consequently, to the intensity of the radiation. The RCA C73435A image conventer tube intended for the measurement of the radiation of light and modified to have an X-ray sensitive photocathode was used for X-ray streak cameras. Practical considerations lead to the use of transparent rather than reflecting photocathodes.