Accession Number : AD0475700

Title :   EL THIN FILM RESEARCH.

Descriptive Note : Rept. for 1 Mar 64-1 Mar 65,

Corporate Author : SIGMATRON INC SANTA BARBARA CA

Personal Author(s) : Soxman, E. J. ; Steele, G. N. ; Sharp, Winston N. ; King, Robert C. ; Schnabel, Lester

Report Date : 07 AUG 1965

Pagination or Media Count : 51

Abstract : An experimental program directed toward the development of large area, crossed electrode, electroluminescent (EL) display panels and emphasizing the use of refined vacuum deposition techniques is described. The ZnS:Mn thin film phosphor used was characterized by a very high sensitivity of EL brightness to applied voltage. In the investigation of deposition techniques, small test panels having a crossed electrode resolution of 33 lines per inch were made. These panels achieved EL brightnesses as high as 1000 Ft-Lamberts when driven continuously by 75 kc/s ac. voltages. By the examination of brightness, voltage and current waveforms over the frequency range of 50 cps to 75 kc/s, it was established that the emitted light consisted mainly of a steady state component with a smaller pulse component occurring when the metal electrode was driven positive. A special vacuum system was designed, assembled and used to develop improved fabrication techniques. These techniques made it possible to produce display panels having an active area of approximately 90 square inches and a crossed electrode resolution of 26-2/3 lines per inch. When driven continuously at 5 kc/s these panels generated 100 Ft-Lamberts. Continuous drive at frequencies exceeding about 15 kc/s resulted in appreciable heating at the ends of the stannic oxide electrodes. The display panels were, however, driven by ac voltages up to about 100 kc/s under pulsed or simulated scan conditions. (Author)

Descriptors :   (*ELECTROLUMINESCENCE, FILMS), PHOSPHORESCENT MATERIALS, BRIGHTNESS, EXCITATION, VOLTAGE, RESOLUTION, ELECTRODES, VAPOR PLATING, VACUUM APPARATUS, ZINC ALLOYS, MANGANESE ALLOYS, SULFIDES, DISPLAY SYSTEMS, SUBSTRATES, PHOTOMICROGRAPHY.

Subject Categories : Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE