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:
1912
Catalogue details

Licence: In copyright

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

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    which is the usual condition; or a convex cylinder might be used in place of the concave cylinder if a higher error is desired. 6. It is obvious, also, that the scissor movement can be Fig. 6o. Fig. 6i. produced by a prism which is made to cover one-half of the pupillary area, but the resulting picture is not so satis- factory for demonstration as that given by the combination lens referred to in Figure 55.