ORGANIC ELECTROLUMINESCENCE DEVICE, ESPECIALLY OBTAINING THE UNIFORM CHROMATICITY OF THE LIGHT

摘要

PURPOSE: An organic electroluminescence device is provided to make the device capable of changing the gradation of a brightness of an emitted light without changing the chromaticity of the light. CONSTITUTION: An organic electroluminescence device(10) includes an organic electroluminescence element(1) and a drive unit(3). The organic electroluminescence element has a pair of electrode and an electroluminescence layer(13) provided between the electrodes. The electroluminescence layer contains at least two types of phosphorescent material, and each phosphorescent material emits color light which is different from color light emitted by the other phosphorescent material. The drive unit, which is electrically connected to the organic electroluminescence element, supplies the organic electroluminescence element a current having a modulated pulse width and a constant amplitude, and causes the organic electroluminescence element to emit light.