Photocell: or photoelectric cell, or electric eye; Solid-state device with a photosensitive cathode that emits electrons when illuminated and an anode for collecting the emitted electrons.

光电管：一种固体探测器，有一个对光灵敏的阴极，受到光照时能发射电子，还有一个用于收集所发射电子的阳极。

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Once an isotope causes the crystal to flash, a photosensitive cathode releases electrons into a vacuum tube where a chain reaction produces a cascade, as in the Geiger counter.

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