Biomed Opt Express. 2020 Oct 7;11(11):6108-6121. doi: 10.1364/BOE.400720. eCollection 2020 Nov 1.
Eccentric photorefraction is an objective technique to determine the refractive errors of the eye. To address the rise in prevalence of visual impairment, especially in rural areas, a minicomputer-based low-cost infrared photorefractor was developed using off-the-shelf hardware components. Clinical validation revealed that the developed infrared photorefractor demonstrated a linear working range between +4.0 D and -6.0 D at 50 cm. Further, measurement of astigmatism from human eye showed absolute error for cylinder of 0.3 D and high correlation for axis assessment. To conclude, feasibility was shown for a low-cost, portable and low-power driven stand-alone device to objectively determine refractive errors, showing potential for screening applications. The developed photorefractor creates a new avenue for telemedicine for ophthalmic measurements.