Transparent thin-film EL display apparatus

Abstract

A transparent thin-film EL display apparatus has a transparent thin-film EL element formed on a glass substrate. A rear substrate consisting of photochromic glass and the glass substrate on which the EL element is formed are disposed facing each other with the EL element located in between. A light-transmitting insulation material is inserted in a space between the two substrates and hermetically sealed. When the display on the EL element becomes hard to see due to light entering from the rear of the display apparatus, the photochromic glass reacts in response to the light and darkens the rear of the EL element, thereby blocking the light. Accordingly, normally the display apparatus displays various items of information through the front substrate and ensures visibility of the background through the display apparatus, and when high-intensity external light enters through the rear, the display apparatus reacts and blocks this light by means of a light shutter function, thereby enabling reliable display of the information without impairment of display contrast, thus guaranteeing a stable and highly reliable display.

Dependencies are inferred from the claim text.