Evaluation of a Transparent Display's Pixel Structure Regarding Subjective Quality of Diffracted See-Through Images

Transparent displays utilizing transparent windows suffer from blurred see-through images caused by diffraction; however, current studies still rely on experiments with actual display panels and human observers to investigate see-through image quality. Moreover, the influence of pixel structure on subjective see-through image quality has not been clearly demonstrated. To improve the inefficient investigation methodology and quantitatively evaluate pixel structure, we first propose a simulation method for diffracted see-through images. Next, by testing six mainstream full-reference image quality assessment algorithms, multiscale structure similarity (MS-SSIM) is revealed to be the most suitable predictor of subjective image quality for our study. Based on public image databases, the influences of aperture ratio, resolution, and the geometry of the transparent window are evaluated by combining the proposed simulation method and MS-SSIM. As a result, an aperture ratio increase of 0.1 leads to a considerable increase of subjective image quality, as more than eight percentage points. Then, a resolution increase of 100PPI only leads to an approximately three percentage point decrease of image quality. Finally, little influence of the geometry of the transparent window is demonstrated. Additionally, physical reasons why these aspects of pixel structure perform in such a manner are also given.