High Contrast Thin Film Electroluminescent Device

An at thin film electroluminescent display device with a structure of anti-reflection layer/glass/ITO/BaTiO₃ /ZnS:Mn/black insulator/Al has been developed which is applicable as an automobile dashboard display.

The device revealed high brightness and high contrast ratio which can be further improved by applying an anti-reflection coating (ARC) on the front glass surface. Under an ambient illumination of 10,000 ft-candle, with a brightness of 200 ft-L, the contrast ratio is 3.5 and increases to 4.5 when an anti-reflection coating is applied. There is a significant improvement compared to the formerly reported one (Contrast ratio = 2, brightness = 125 ft-L, under the same illumination).