Retinoscopy : (or shadow test) in the determination of refraction at one meter distance, with the plane mirror / by James Thorington.

  • Thorington, James, 1858-1944.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Retinoscopy : (or shadow test) in the determination of refraction at one meter distance, with the plane mirror / by James Thorington. Source: Wellcome Collection.

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    highly the shadow test, yet he would remind those who try retinoscopy, fail, and then ridicule it, that the fault with them is back and not in front of the mirror. Suggestions to the Beginner.—To obtain profi- ciency in retinoscopy there is much to be understood. Careful attention to details must be given, and not a little patience possessed, as it is not a method that is acquired in a day, and it is only after weeks of con- stant application that accuracy is acquired. There- fore the beginner is strongly advised to learn the major points from one of the many schematic eyes in the market before attempting the human eye. At the same time he should be perfectly familiar with the laws of refraction and dioptrics, as an understand- ing of conjugate foci is really the underlying prin- ciple of the method—i. e., a point on the retina being one focus and the myopic or artifically-made far- point the other focus. What is meant by major points applies more par- ticularly to the study of the retinal illumination, its direction and apparent rate of movement, also its form, the distance between the observer and the patient, how to handle the mirror, etc., all of which are referred to under their special headings.