sentence: Eye relief can be particularly important for eyeglass wearers.
sentences_before: It is the distance the observer must position his or her eye behind the eyepiece in order to see the image. The longer the focal length of the eyepiece, the greater the eye relief. Binoculars may have eye relief ranging from a few millimeters to 2.5 centimeters or more.
concept_name: eye relief
headings: Binoculars Features
categories: Optics Tools