Abstract: A multiple section photomultiplier tube. The tube is constructed essentially as a matrix of several independent tubes in one envelope. The photocathode of each individual section of the tube is formed into an independent surface, and the photocathode to dynode spacings are isolated by a configuration built with separator electrodes which connect to photocathode boundary dividers formed in the faceplate. The boundary dividers also isolate the independent photocathode regions. The boundary dividers can be either slots into which the separator electrodes fit or ribs with which the separator electrodes are engaged.

Abstract: A multiple section photomultiplier tube constructed as a matrix of several independent tubes in one envelope. The photocathode to dynode spacings are isolated by a separator configuration built with walls which interlock in cooperating slots, and each photocathode operates with its own independent dynode cage. One dynode in each cage is maintained electrically independent, and its connection is brought out of the envelope independently. This permits independent adjustment of the gain for each of the tube's multiple sections, so they can be adjusted to the same response for a standard radiation signal. The entire tube can then be used to monitor a large area for radiation, and will yield the same response over its entire cathode area.

Abstract: A focusing electrode structure for a photomultiplier tube which optimizes the tube operation. One or more focusing electrodes located between the photocathode and the first dynode are configured in the shape of substantial sections of a spheroid dome with the smaller opening nearer to the photocathode. In the preferred embodiment three focusing electrodes are used with their sizes increasing and their voltages decreasing as they approach the photocathode.

Abstract: A so-called "solar-blind" photomultiplier tube includes an envelope having a sidewall and an input faceplate formed from an ultraviolet transmitting filter. A photoemissive cathode is disposed within the envelope for providing photoelectrons in response to radiation incident thereon. The cathode has an intrinsic responsivity extending from the near-ultraviolet portion through the visible portion of the electromagnetic spectrum; however, the filter faceplate transmits only the ultraviolet portion of the spectrum to the photoemissive cathode. The combination of the filter faceplate and the photoemissive cathode therefore limits the tube to a responsivity within the wavelength range of about 300 to less than 400 nanometers.