Abstract: The invention relates to a lead silicate glass, to the use thereof for the production of secondary electron multipliers, and to a process for setting a reduced surface resistance of a lead silicate glass of this type. The lead silicate glass has the following composition (in % by weight): SiO2 15-35, PbO 35-55, Bi2O3>20-29, BaO 0-10, Cs2O 0-10, BaO+Cs2O 2-13, CaO 0-10, SrO 0-10, CaO+SrO+BaO 0-10, and up to 1% by weight of conventional fining agents. The surface resistance of the lead silicate glass after reduction in a hydrogen atmosphere is from 0.1 to 60 M&OHgr;/sq.

Abstract: A photosensor comprises a cathode portion (111) sensitive to radiation and/or particles, an anode portion (114) receiving electrons, an evacuated channel (112, 113, 200) having the cathode portion attached to its one end portion in a vacuum-tight manner and the anode portion attached to its other end portion in a vacuum-tight manner, a conductive or semiconductive layer (107) at least partially covering the inner surface of the evacuated channel, wherein the channel is formed of a tubular member (106). A method of manufacturing a channel electron multiplier comprises the steps of forming a tubular member and a conductive or semiconductive layer at least on parts of its inner surface, forming an anode portion and sealing it to the tubular member, evacuating the tubular member, forming a cathode portion sensitive to radiation and/or particles, and sealing the cathode portion to the evacuated tubular member. The detector may at least partially be packed into a casting compound.