Apparatus and method of determining an eye prescription

Durr NJ, Lage E, Dave S
US Patent 9,854,965, WO Application PCT/US2014/045305 2014.
Google Patent Link

Abstract

Eye prescriptions may be determined by providing a simple, easy to use, portable device with a specially configured targeting light source that aligns the eye, mitigates accommodation, and provides accurate results. Unlike stationary, closed view autorefractors, this device typically is portable, self-usable, relatively inexpensive, enabling more widespread use across the world.