A brief description is given of the history and early application of light coagulation in ophthalmology. The technique was originally developed by Meyer-Schwickerath in 1949 following clinical observation of macular damage sustained from watching an eclipse. A variety of different light sources were attempted in the prototype instruments before Carl Zeiss (Oberkochen) developed the first commercial model using a high-pressure Xenon lamp in combination with an ophthalmoscopic view of the funds. The ophthalmological clinical procedure originally advocated by Meyer-Schwickerath for light coagulation is briefly outlined and its potential application as a prophylactic treatment in certain specified pathologies is indicated.