detector so that only a small portion of the electron image hits the detector at any given moment. As time passes the electron image is deflected back and forth and up and down so that the entire image, portion by portion, can be read by the detector. The output from the detector is an electric current whose magnitude(/)is a measure of brightness at a specific point on the image. Electrons that do not hit the single detector are wasted, rather than stored on the target as in the image orthic。n摄象管 which accounts in part for its low sensitivity. It has no"storage characteristic The image orthicon tube ( often abbreviated as lO)was common until the 1960s. A com bination of Farnsworth's image dissector and RCAs orthicon technologies, it replaced the iconoscope光电析象 Orthicon, which required a great deal of light to work adequately While the iconoscope and the intermediate orthicon used capacitance(*)between a multitude of small but discrete light sensitive collectors and an isolated signal plate for reading video 2021/220P12021/2/20 P.11 detector so that only a small portion of the electron image hits the detector at any given moment. As time passes the electron image is deflected back and forth and up and down so that the entire image, portion by portion, can be read by the detector. The output from the detector is an electric current whose magnitude (大小)is a measure of brightness at a specific point on the image. Electrons that do not hit the single detector are wasted, rather than stored on the target as in the image orthicon(摄象管)which accounts in part for its low sensitivity. It has no "storage characteristic". The image orthicon tube (often abbreviated as IO) was common until the 1960s. A combination of Farnsworth's image dissector and RCA's orthicon technologies, it replaced the iconoscope(光电析象 管)/orthicon, which required a great deal of light to work adequately. While the iconoscope and the intermediate orthicon used capacitance(电容) between a multitude of small but discrete light sensitive collectors and an isolated signal plate for reading video