ABSTRACT
Therapeutic lasers were originally developed in the early 1960s as an effective alternative to a bright (xenon) light source used in ophthalmology for photocoagulation of the retina. The early ophthalmic ruby laser was little more than a prototype commercial or scientific laser connected inflexibly to a microscope to "cross hair site" the target. Even as the earliest devices provided a magnified field, the only mechanism to deliver the laser beam was by moving the patient under the cross hair.
