Study on how to improve visibility of transparent display for augmented reality under various environment conditions

In this paper, a psychophysical investigation to improve a visibility of a transparent display is presented. A new illuminance measurement method for the transparent display, named eye illuminance, is proposed. Through a psychophysical experiment, it is found that the eye illuminance is strongly related with the visibility of the transparent display regardless of its background condition. This paper finds out the optimum emission luminance range of the transparent display under various illuminant conditions. Also, the contrast ratio for visibility is analyzed and it is found that a higher contrast ratio is not needed to provide a visually better image under a brighter ambient environment. In conclusion, our findings will contribute to an auto brightness control technology to improve the visibility of the transparent display for augmented reality devices.