See-Through Image Blurring of Transparent Organic Light-Emitting Diodes Display: Calculation Method Based on Diffraction and Analysis of Pixel Structures

In this paper, the issue of see-through image blurring of transparent organic light-emitting diodes display is demonstrated, and a systematic method is proposed to calculate blurred see-through image based on diffraction theory. In the calculation, distances of background object and the viewer are considered to correct Fresnel diffraction and chromatic image can be finally synthesized. Calculated and actually captured see-through images match well by using different background distances and pixel structures to verify, as error ratio of only 2.3% and 4.3%, respectively, in the term of blurred image's fringe length. Based on the calculation results, see-through image qualities corresponding to four pixel structures are evaluated and two structures are verified to have better image quality. Finally, higher resolutions that lead to much more significant see-through image blurring are discussed.

I. Introduction

Recent years, organic light-emitting diodes (OLED) technology has gained increasing attentions because it enables vivid, thin and bright panel for next-generation display [1], [2]. In addition to these attractive features, OLED display can be made flexible and transparent to provide possibilities of new applications [2] –[5]. Especially, transparent OLED display can be adopted in some emerging applications, like showcase window, eyeglasses, full-windshield head-up display etc. [6], [7], which makes a large amount of research dedicated to it these years. While discussing transparent OLED display, displayed image (foreground) and see-through image (background) are both desired to be with high quality. For this purpose, there has been plenty of research focused on displayed image quality, like its resolution, brightness, contrast, saturation etc. [2], [8], [9]. However, see-through image quality has gained much less attention whereas it is indispensable to determine the overall quality of transparent OLED display.