Retinoscopy has, over the years, become increasingly accepted as a valuable technique. Most refractionists employ it regularly, each putting more or less emphasis on it according to the scheme of refraction he follows. Even the arguments concerning the name of the process have died away and, in this country, voices are rarely lifted to point out the fallacy of the term "retinoscopy" and to advance some more rational name such as "skiascopy" or "korescopy." Once more usage has triumphed over purism.
In view of the great expenditure of time and effort made daily by refractionists plying retinoscopes, it is surprising that so little is written on the subject.
Duke-Elder1 characteristically gives an excellent presentation of the subject and indicates quite clearly the reasons for the alterations in speed of the reflex. He does not, however, set forth the equations which would allow one to calculate the speed. I shall
SAFIR A. The Speed of the Retinoscopic Reflex. Arch Ophthalmol. 1961;65(6):785-788. doi:10.1001/archopht.1961.01840020787005