Improvement of equipment characteristics, using photodetectors, first of all is connected with increasing of the photocathode sensitivity and possibility to operate in new spectral ranges.

The last years' developments of Photomultiplier Tubes (PMTs) in the “Electron” National Research Institute are presented. There were a number of PMTs with superior characteristics developed during the last decade. Among these are such devices as PMTs with low radiation background, microchannel plate PMTs (MCP-PMT), PMTs with GaAs photocathodes. The latest developments of the new kind and innovative range of photodetectors, and such novel devices as Fine-Mesh PMTs for high magnetic field environment and proximity focused Hybrid PMTs (HPMT) with an electron bombarded p-i-n diode are also discussed.

Small grained maraging steel has a higher ductility than the large grained steel but in a number of cases the influence of the grain size is masked by other singularities of the steel.