Gonioscoper 3 Mirror is a small and compact optical tool which is commonly used by the ophthalmologist for the painless and easy examination of the drainage area of your eye which lies in between the iris and the cornea where aqueous humor drains out of your eye. This tool helps to check whether the drainage angle functions properly or not. Gonioscoper 3 Mirror is precisely designed and helps to overcome the problems occurred due to total internal reflection.