摘要: Photodetectors are classed here and treated together with their operational features. Various types of thermal detectors briefly examined. Photoemissive such as vacuum phototubes photomultipliers discussed in detail. Then CCD cameras, photodetectors the internal photoeffect, luminescence quantum counters, photoionization chambers discussed. The basic principles advantages well-established actinometers chemical shown here. Much attention is given to gas-phase operating visible, UV, especially UV spectral range.