PURPOSE: To enable the incidence position of secondary electrons to be detected with high accuracy by causing the secondary-electron-discharging surface of a final stage dynode to have uniform sheet resistivity and connecting electrodes for supplying a current to the final stage dynode to it thereby producing positional signals.
CONSTITUTION: Photoelectrons produced by photons becoming incident upon a photoelectric screen 2 are intensified by a transmission-type dynode group 3 before becoming incident upon a final stage dynode 5. Since the secondary- electron-discharging surface of the dynode 5 has uniform sheet resistivity, the signal outputs produced by electrodes 11, 12, 13 and 14 contain information about the incidence positions of the intensified secondary electrons. The outputs of charge amplifiers 21 and 22 are connected to an adder 25 and a subtractor 26 and the output terminals of the adder 25 and the subtractor 26 are connected to a divider 27. The output of the divider 27 is represented by the signal of the X-axis on the coordinates.
KUME HIDEHIRO
MURAMATSU SHINICHI
IIDA MASAHIRO
