When we transform instantaneously the fundamental nature of the cornea from a reflecting into a diffusing surface, a new technique of photokeratoscopy is possible. One of the most important advantages of this method is that the localization of the photographed object on the surface can be easily located. The accuracy of this method will be proportional to dy/dx: that means it wilt increase from the center to the periphery contrary to most other methods in which the precision of the x coordinate decreases from the arbitrarily chosen point (center) to the periphery, due to stepwise integration. The accuracy of this technique is 0.05 mm at the extreme corneal periphery.