Low-Voltage Electron Diffraction Tube

Abstract

A SEALED-OFF cathode ray tube for demonstration of electron diffraction patterns at low voltages (6,000–7,000 volts) has already been described by me¹. We have recently carried out experiments with this tube at lower voltages and have found that the electron diffraction patterns are quite visible on the fluorescent screen down to 4,000 volts and just visible down to 2,000 volts. Photographic records of electron diffraction patterns could therefore be made using electrons of only 2,000 volts energy.