Search results
Results from the WOW.Com Content Network
An Abbe–Koenig prism is a type of reflecting prism, used to invert an image (rotate it by 180°). They are commonly used in binoculars and some telescopes for this purpose. The prism is named after Ernst Abbe and Albert Koenig . The prism is made from two glass prisms, which are optically cemented together to form a symmetric, shallow Vee ...
Prism adaptation. Prism adaptation is a sensory-motor adaptation that occurs after the visual field has been artificially shifted laterally or vertically. It was first introduced by Hermann von Helmholtz in late 19th-century Germany as supportive evidence for his perceptual learning theory (Helmholtz, 1909/1962). [1]
Visual perception is the ability to interpret the surrounding environment through photopic vision (daytime vision), color vision, scotopic vision (night vision), and mesopic vision (twilight vision), using light in the visible spectrum reflected by objects in the environment. This is different from visual acuity, which refers to how clearly a ...
The extraocular muscles, or extrinsic ocular muscles, are the seven extrinsic muscles of the eye in humans and other animals. [1] Six of the extraocular muscles, the four recti muscles, and the superior and inferior oblique muscles, control movement of the eye. The other muscle, the levator palpebrae superioris, controls eyelid elevation.
An Uppendahl prism [1] is an erecting prism, i.e. a special reflection prism that is used to invert an image (rotation by 180°). The erecting system consists of three partial prisms made of optical glass with a high refractive index cemented together to form a symmetric assembly and is [2] used in microscopy as well as in binoculars technology.
Purpose. assess alignment of both eyes. The Four Prism Dioptre Reflex Test (also known as the 4 PRT, or 4 Prism Dioptre Base-out Test) is an objective, non-dissociative test used to prove the alignment of both eyes (i.e. the presence of binocular single vision) by assessing motor fusion. [1] Through the use of a 4 dioptre base out prism ...
The Eye of Horus, also known as left wedjat eye or udjat eye, specular to the Eye of Ra (right wedjat eye), is a concept and symbol in ancient Egyptian religion that represents well-being, healing, and protection. It derives from the mythical conflict between the god Horus with his rival Set, in which Set tore out or destroyed one or both of ...
Sixth nerve palsy, or abducens nerve palsy, is a disorder associated with dysfunction of cranial nerve VI (the abducens nerve ), which is responsible for causing contraction of the lateral rectus muscle to abduct (i.e., turn out) the eye. [1] The inability of an eye to turn outward, results in a convergent strabismus or esotropia of which the ...