Search results
Results From The WOW.Com Content Network
The exit pupil is the image of the aperture stop formed by the optics behind it, and the location and size of the pupil are determined by chief rays and marginal rays. The image side of the lens of an SLR camera; the exit pupil is the light area in the middle of the lens. In optics, the exit pupil is a virtual aperture in an
The entrance pupil is the image of the aperture stop viewed from the front of the optical system and here it is a virtual image. Chief rays and marginal rays determine the location and the size of the entrance pupil, respectively. A camera lens adjusted for large and small aperture. The visible opening is the entrance pupil of the lens.
The exit pupil is located at infinity, and chief rays after the objective are parallel to the optical axis. An image-space telecentric lens has the exit pupil (the image of the aperture stop formed by optics after it) at infinity and produces images of the same size regardless of the distance between the lens and the film or image sensor. This ...
Typical eye relief distances for telescopic sights are often between one and four inches (25 to 100 mm), as opposed to the much shorter 15 to 17 mm for typical binoculars. The exit pupil widths in rifle sights are designed to be larger than the eye's pupil, to allow for a range of motion without vignetting.
The pupil magnification of an optical system is the ratio of the diameter of the exit pupil to the diameter of the entrance pupil.The pupil magnification is used in calculations of the effective f-number, which affects a number of important elements related to optics, such as exposure, diffraction, and depth of field.
For example, if a lens's focal length were 100 mm and its entrance pupil's diameter were 50 mm, the f-number would be 2. This would be expressed as " f /2 " in a lens system. The aperture diameter would be equal to f/2. Camera lenses often include an adjustable diaphragm, which changes the size of the aperture stop and thus the entrance pupil ...
Another way of preventing myopia progression includes using low-dose atropine eye drops, which are typically used to help dilate pupils during an eye exam, according to HealthyChildren.org.
Since the entrance pupil and exit pupil are images of the aperture stop, for a real image pupil, the lateral distance of the marginal ray from the optical axis at the pupil location defines the pupil size. For a virtual image pupil, an extended line, forward along the marginal ray before the first optical element or backward along the marginal ...