The eye relief of an optical instrument (such as a telescope, a microscope, or binoculars) is the distance from the last surface of an eyepiece at which the user's eye can obtain the full viewing angle. If a viewer's eye is outside this distance, a reduced field of view will be obtained. The calculation of eye relief is complex, though generally, the higher the magnification and the larger the intended field-of-view, the shorter the eye relief.
Read more about Eye Relief: Eye Relief and Exit Pupil, Available Eye Relief, Adding Prescription Lenses
Famous quotes containing the words eye and/or relief:
“Nature seems to have taken a particular Care to disseminate her Blessings among the different Regions of the World, with an Eye to this mutual Intercourse and Traffick among Mankind, that the Natives of the several Parts of the Globe might have a kind of Dependance [sic] upon one another, and be united together by their common Interest.”
—Joseph Addison (1672–1719)
“Nowadays, if New York has a heart, it might be the Garden. Almost everyone goes there, for one purpose or another. There are dog shows, and Sonja Henie and mass meetings.”
—In New York City, U.S. public relief program (1935-1943)