enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    The most common application for this is the treatment of strabismus. By moving the image in front of the deviated eye, double vision can be avoided and comfortable binocular vision can be achieved. Other applications include yoked prism where the image is shifted an equal amount in each eye.

  3. Prism cover test - Wikipedia

    en.wikipedia.org/wiki/Prism_Cover_Test

    The prism cover test ( PCT) is an objective measurement and the gold standard in measuring strabismus, i.e. ocular misalignment, or a deviation of the eye. [1] It is used by ophthalmologists and orthoptists in order to measure the vertical and horizontal deviation and includes both manifest and latent components. [1]

  4. Eyeglass prescription - Wikipedia

    en.wikipedia.org/wiki/Eyeglass_prescription

    Prism and Base Prism refers to a displacement of the image through the lens, often used to treat strabismus and other binocular vision disorders. The prism value is measured in prism diopters, and Base refers to the direction of displacement.

  5. Strabismus surgery - Wikipedia

    en.wikipedia.org/wiki/Strabismus_surgery

    Strabismus surgery (also: extraocular muscle surgery, eye muscle surgery, or eye alignment surgery) is surgery on the extraocular muscles to correct strabismus, the misalignment of the eyes. [1]

  6. Prism (optics) - Wikipedia

    en.wikipedia.org/wiki/Prism_(optics)

    An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides.

  7. Binoculars - Wikipedia

    en.wikipedia.org/wiki/Binoculars

    In roof prism designs, optically relevant prism angles must be correct within 2 arcseconds ( 1/1,800 of 1 degree) to avoid seeing an obstructive double image. Maintaining such tight production tolerances for the alignment of their optical elements by laser or interference (collimation) at an affordable price point is challenging.

  8. Refractometer - Wikipedia

    en.wikipedia.org/wiki/Refractometer

    A refractometer is a laboratory or field device for the measurement of an index of refraction ( refractometry ). The index of refraction is calculated from the observed refraction angle using Snell's law. For mixtures, the index of refraction then allows the concentration to be determined using mixing rules such as the Gladstone–Dale relation and Lorentz–Lorenz equation .

  9. Prentice position - Wikipedia

    en.wikipedia.org/wiki/Prentice_position

    The Prentice position is an orientation of a prism, used in optics, optometry and ophthalmology. [1] In this position, named after the optician Charles F. Prentice, the prism is oriented such that light enters it at an angle of 90° to the first surface, so that the beam does not refract at that surface. All the deviation caused by the prism ...

  10. Aberrations of the eye - Wikipedia

    en.wikipedia.org/wiki/Aberrations_of_the_eye

    Low order aberrations include Myopia (positive defocus), hyperopia (negative defocus), and regular astigmatism. Other lower-order aberrations are non- visually significant aberrations known as first order aberrations, such as prisms and zero-order aberrations (piston).

  11. Distortion (optics) - Wikipedia

    en.wikipedia.org/wiki/Distortion_(optics)

    Distortion (optics) In geometric optics, distortion is a deviation from rectilinear projection; a projection in which straight lines in a scene remain straight in an image. It is a form of optical aberration .