RaPiD: a Raspberry Pi-based optical fundoscope

fundus camera is one of the most widely used tools for retinal examination and is used for the diagnosis of several eye diseases. Most retinal fundus imaging devices operate within a laboratory environment. They are expensive and have limited reach in rural areas, particularly in developing countries. Making the fundus imaging devices low-cost, portable, and rugged would make access to eye care affordable. In this paper, we explain the development of a Raspberry Pi-based fundus imaging device equipped with an 8-megapixel sensor array and with a field of view of 45^∘ . The device operates in the mydriatic mode, i.e., it requires the pupil to be dilated. One of the shortcomings of a low-cost fundus imaging prototype is the reflection of the light source on the condenser lens, which we overcome using an innovative arrangement of the polarizers.