a now obsolete picture pickup tube in a television camera; electrons emitted from a photoemissive surface in proportion to the intensity of the incident light are focused onto the target causing secondary emission of electrons
同义词：orthicon
英汉双解词典包含3185865条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。