A haploscope is an optical device for presenting one image to one
eye and another image to the other eye. The word derives from two
Greek root
The English language uses many Greek and Latin roots, stems, and prefixes. These roots are listed alphabetically on three pages:
* Greek and Latin roots from A to G
* Greek and Latin roots from H to O
* Greek and Latin roots from P to Z.
Some ...
s: ''haploieides'', single and ''skopeo'', to view. The word is often used interchangeably with
stereoscope
A stereoscope is a device for viewing a stereoscopic pair of separate images, depicting left-eye and right-eye views of the same scene, as a single three-dimensional image.
A typical stereoscope provides each eye with a lens that makes the ima ...
, but it is more general than that. A stereoscope is a type of haploscope, but not vice versa. The word has more currency in the
medical
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practic ...
field than elsewhere, where it refers to instruments designed to test
binocular vision
In biology, binocular vision is a type of vision in which an animal has two eyes capable of facing the same direction to perceive a single three-dimensional image of its surroundings. Binocular vision does not typically refer to vision where an ...
. These instruments include
Worth's amblyoscope and the
synoptophore.
Commonly haploscopes employ front-surfaced
mirror
A mirror or looking glass is an object that Reflection (physics), reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the ...
s placed at different angles close to the eyes to reflect the images into the eyes. Reputedly the largest haploscope, with images of over a meter (in fact, 4 feet) square and a viewing distance for each eye of nearly five meters (16 feet), was constructed by
Vaegan in about 1975 to research
stereoacuity.
The large images allowed very small
retinal disparities to be presented.
See also
*
Cheiroscope A cheiroscope (also: ''chiroscope'') is an optical device consisting of a viewing instrument equipped with a drawing pad, with the viewing instrument set up as a haploscope that blends a left and/or right image into view over the drawing.
The chei ...
*
Diplopia
Diplopia is the simultaneous perception of two images of a single object that may be displaced horizontally or vertically in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often v ...
*
Amblyopia
Amblyopia, also called lazy eye, is a disorder of sight in which the brain fails to fully process input from one eye and over time favors the other eye. It results in decreased vision in an eye that typically appears normal in other aspects. Amb ...
*
Orthoptist
Orthoptics is a profession allied to the eye care profession. Orthoptists are the experts in diagnosing and treating defects in eye movements and problems with how the eyes work together, called binocular vision. These can be caused by issues with ...
References
{{reflist
External links
International Orthoptics AssociationOrthoptics Association of Australia
Optical devices