Vision enhancement: defocus correction via optical see-through head-mounted displays

Vision is our primary, essential sense to perceive the real world. Human beings have been keen to enhance the limit of the eye function by inventing various vision devices such as corrective glasses, sunglasses, telescopes, and night vision goggles. Recently, Optical See-Through Head-Mounted Displays (OST-HMD) have penetrated in the commercial market. While the traditional devices have improved our vision by altering or replacing it, OST-HMDs can augment and mediate it. We believe that future OST-HMDs will dramatically improve our vision capability, combined with wearable sensing systems including image sensors. For taking a step toward this future, this paper investigates Vision Enhancement (VE) techniques via OST-HMDs. We aim at correcting optical defects of human eyes, especially defocus, by overlaying a compensation image on the user's actual view so that the filter cancels the aberration. Our contributions are threefold. Firstly, we formulate our method by taking the optical relationships between OST-HMD and human eye into consideration. Secondly, we demonstrate the method in proof-of-concept experiments. Lastly and most importantly, we provide a thorough analysis of the results including limitations of the current system, potential research issues necessary for realizing practical VE systems, and possible solutions for the issues for future research.