ABSTRACT
This chapter describes the mechanism of the photoconductive camera tube covering past types and the ultrahigh-sensitivity high-gain avalanche rushing amorphous photoconductor, HARP tube based on a new operating principle. Camera tubes come in two main types: an image camera tube that uses an external photoelectric effect and a photoconductive camera tube that uses the photoconducting effect, a type of internal photoelectric effect. The scanning electron beam system of the camera tube is classified in terms of electric-field/magnetic-field combinations used for focusing and deflecting the beam. The electron-injection-amplification target can be divided into injection type and blocking type. The chapter summarizes the research conducted so far into HARP camera tubes and describes the features of ultrahigh sensitivity cameras that use them. It describes the principal characteristics of the ultrahigh-sensitivity HARP camera tube with a target film thickness of 25µm.
