Using a gas plasma as a source of free electrons. a brightness of 60 fL is obtained from an extended layer of ZnO phosphor with about 5 V applied to it. The phosphor efficiency. >10 Im/W, shows little change during 5000 h of operation. For display purposes devices have been constructed incorporating multiple phosphor-coated anodes whose potentials are controlled by low-voltage semiconductor circuits. © 1971, IEEE. All rights reserved.