Having eye problems? The ophthalmoscope is the tool the doctors use to check eyes. On the ophthalmoscope is a bright light that the doctor points at your eye to check it. It might be hard to keep your eyes open, but you have to try! The ophthalmoscope helps doctor detect external issues as well as internal problems in the eye such as internal bleeding or anything showing signs of diabetes. Yes, signs of diabetes can be detected from the eyes, and this is a big reason why doctors use an ophthalmoscope.