The development of flat panel PMT

In High Energy Physics (HEP) experiment and scintillation counting application, a photodetector, which can cover large area and has small dead space, has been desired. It should be compact and should have multi-anode in some cases. Hamamatsu has developed a Flat Panel Photomultiplier (PMT) to meet the demand. If many of Flat Panel PMTs are placed closely, they can cover large area as one photodetector. The Flat Panel PMT has 51.7×51.7×12.4 mm metal package and 8×8 matrix multi-anode. Some prototypes were made, and it was confirmed that a ratio between external size and useful area was 90% and gain of 3×10⁵ was achieved. Its structure and basic feature are discussed in this paper