Wide-angle noncontact and small-angle contact cameras.

The theoretical wide-angle model of the human eye and the principle of separation of ophthalmoscopic illumination and observation apertures have been used to design two fundamentally different ophthalmoscopic cameras: a 90 degree wide-angle, noncontact camera and a high-resolution macula-disc camera. The chief advantage of the 90 degree noncontact camera is the increase in contrast achieved by eliminating from the retinal image light reflections off corneal and lenticular surfaces. This contrast increase is obtained in addition to a wide-angle field, while the resolution of current fundus cameras is maintained. The chief advantage of the macula-disk camera is that it records the first image of the patient's fundus and thus permits an actual increase in resolution of retinal detail not obtainable with current fundus cameras. This additional detail should greatly facilitate future clinical study and treatment of macular disease.