![Binoviewer](https://upload.wikimedia.org/wikipedia/commons/c/c2/Binoviewer.png)
A binoviewer is an
optical
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...
device designed to enable
binocular
Binocular may refer to:
Science and technology
* Binocular vision, seeing with two eyes
* Binoculars, a telescopic tool
* Binocular microscope, binocular viewing of objects through a single objective lens
Other uses
* Binocular (horse), a thoroug ...
viewing through a single
objective
Objective may refer to:
* Objective (optics), an element in a camera or microscope
* ''The Objective'', a 2008 science fiction horror film
* Objective pronoun, a personal pronoun that is used as a grammatical object
* Objective Productions, a Brit ...
.
In contrast to
binoculars
Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. Most binoculars are sized to be held ...
, it allows partially
stereoscopic viewing and partially monoculair viewing, this because the eyes and brain still process the image binocularly, as both images are produced by the same objective and do not differ except for
aberrations induced by the binoviewer itself.
A binoviewer consists of a
beam splitter
A beam splitter or ''beamsplitter'' is an optical device that splits a beam of light into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding wide ...
which splits the image provided by the objective into two identical (but fainter) copies, and a system of
prisms or mirrors that relay the images to a pair of identical
eyepiece
An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as telescopes and microscopes. It is named because it is usually the lens that is closest to the eye when someone looks through the device. The ...
s.
Binoviewers are a standard component of laboratory
microscopes
A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisibl ...
and are also used with
optical telescope
An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electro ...
s, particularly in
amateur astronomy
Amateur astronomy is a hobby where participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes. Even though scientific research may not be their primary goal, some amateur astronomers m ...
.
Optical devices
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