The Prentice position is an orientation of a prism, used in optics, optometry and ophthalmology.[1] In this position, named after the optician Charles F. Prentice, the prism is oriented such that light enters it at an angle of 90° to the first surface, so that the beam does not refract at that surface. All the deviation caused by the prism takes place at the exit surface.
![](http://up.wiki.x.io/wikipedia/commons/thumb/9/9b/Prentice_position.svg/220px-Prentice_position.svg.png)
In ophthalmology, glass prisms were classically calibrated for use in the Prentice position, while plastic prisms were calibrated for use in the frontal position.[2]
See also
editReferences
edit- ^ Elkington, A.R.; Frank, H.J.; Greaney, M.J. (25 August 1999). Clinical Optics (3 ed.). ISBN 0-632-04989-8.
- ^ Thompson, J.T.; Guyton, D.L. (March 1983). "Ophthalmic prisms. Measurement errors and how to minimize them". Ophthalmology. 90 (3): 204–10. doi:10.1016/S0161-6420(83)34572-3. PMID 6866442.