Dynamic image pre-compensation for computer access by individuals with ocular aberrations

Several image enhancement methods have been successfully used to improve the visual perception of patients with eye diseases, such as Age-related Macular Degeneration and Cataracts, on images displayed on TV and computers. However, few developments aim to enhance the visual performance of computer users with general ocular aberrations. This paper proposes an image enhancement approach based on dynamic pre-compensation for improving the visual performance of subjects with ocular aberrations, while interacting with computers. The degradation caused by ocular aberrations is counteracted through the pre-compensation performed on images displayed on the computer screen. As the ocular aberration initially measured as a priori information is related with a specific pupil size, real-time pupil size data are collected to recalculate and update the pre-compensation to match the corresponding aberrations. An icon recognition experiment, involving human subjects, was designed and implemented to evaluate the performance of the proposed method. The experimental results show that the proposed method significantly increased the number of icons correctly recognized, which confirmed that the dynamic pre-compensation is effective in improving the visual performance of computer users with ocular aberrations.

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