Emission of dispersed‐type inorganic EL devices with frequency‐variable high‐voltage oscillation circuit. Issue 1 (9th November 2018)

• Record Type: Journal Article
• Authors: Sato, Shuichi; Shimizu, Tomohisa; Ohuchi, Mikio
• Is Part Of: Journal of the Society for Information Display. Volume 27:Issue 1(2019)
• Page Start: 3
• Page End: 12
• Publication Date: 2018-11-09
• Subjects: driver circuit -- electroluminescence -- inorganic -- organic dye -- oscillation circuit -- ZnS:Cu, Cl; Information display systems -- Periodicals; 621.38154205
• DOI: 10.1002/jsid.744
• Languages: English
• ISSNs: 1071-0922

Abstract

Abstract: Dispersed‐type inorganic electroluminescent (EL) devices composed of a transparent electrode, a phosphor, a dielectric, and a back electrode were prepared under various conditions using a zinc sulfide (ZnS)‐based phosphor. Additionally, a voltage/frequency variable circuit was designed. A compact high‐voltage/frequency variable circuit including three modules for boosting, frequency conversion, and voltage conversion was designed. A 140 Vpp voltage and a frequency in the range of 270 Hz to 2.4 kHz can be controlled by this circuit. The emission has begun to be observed at a voltage about 60 Vpp and a frequency of 400 Hz, at a voltage about 40 Vpp and a frequency of 1.4 kHz, 2.4 kHz, respectively. The emission intensity increased with an increase in frequency; emission with a wavelength of 450 nm was strongly influenced by the frequency. The luminescence and the electrical properties were affected by the preparation conditions including device structures, dispersion of ZnS:Cu, and Cl particles because of the current path generated by defects in the EL cell. Abstract : Dispersed‐type inorganic electroluminescent devices were prepared under various conditions using a zinc sulfide‐based phosphor including organic dye. Additionally, a compact voltage/frequency variable circuit was designed. The driving characteristics were systematically investigated including their luminescence and electrical properties.