A biomicroscopy test is widely known as a slit lamp exam. In this test, your eyes are being examined microscopically. This helps your ophthalmologist to detect any problems or abnormalities that are there in your eye. It can be used to diagnose a range of problems such as detached retina, retinal vessel blockage, macular degeneration, cataracts, and cornea injury. There is not much risk involved with this type of test but if you do experience any type of discomfort then you should contact your ophthalmologist immediately. It is normal for you to feel increasingly sensitive to light.