Estimation of Spherical Refractive Errors Using Virtual Reality Headset

Refractive errors are the most common visual defects in humans. They are corrected using lenses whose power is determined using expensive and bulky devices operated by trained professionals. This limits the outreach of eye- health care. We exploit commercial virtual reality (VR) setup to create a portable and inexpensive system for subjective estimation of spherical refractive errors. In doing so, we aim to keep hardware additions simple and to a minimum. We add a plain reflecting mirror in a VR headset to project optotypes on programmable focal planes at varying distances from the subject's eye. An interactive interface uses feedback from the user to estimate accommodation range and spherical refractive errors automatically. We compute the range and precision of our system, and validate them in a user trial study. The proposed setup strongly agrees with clinical subjective refraction.