enow.com Web Search

Search results

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

    en.wikipedia.org/wiki/Prism_correction

    Yoked prism can move the image away from primary gaze without the need for a constant head tilt or turn. Prism correction is measured in prism dioptres. A prescription that specifies prism correction will also specify the "base". The base is the thickest part of the lens and is opposite from the apex.

  3. Presbyopia - Wikipedia

    en.wikipedia.org/wiki/Presbyopia

    Presbyopia is a typical part of the aging process. [4] It occurs due to age related changes in the lens (decreased elasticity and increased hardness) and ciliary muscle (decreased strength and ability to move the lens), causing the eye to focus right behind rather than on the retina when looking at close objects. [4]

  4. List of optics equations - Wikipedia

    en.wikipedia.org/wiki/List_of_optics_equations

    Visulization of flux through differential area and solid angle. As always ^ is the unit normal to the incident surface A, = ^, and ^ is a unit vector in the direction of incident flux on the area element, θ is the angle between them.

  5. Prism (optics) - Wikipedia

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

    Prism spectacles with a single prism perform a relative displacement of the two eyes, thereby correcting eso-, exo, hyper- or hypotropia. In contrast, spectacles with prisms of equal power for both eyes, called yoked prisms (also: conjugate prisms, ambient lenses or performance glasses) shift the visual field of both eyes to the same extent.

  6. Cauchy's equation - Wikipedia

    en.wikipedia.org/wiki/Cauchy's_equation

    It deviates in the ultraviolet and infrared regions. In optics, Cauchy's transmission equation is an empirical relationship between the refractive index and wavelength of light for a particular transparent material. It is named for the mathematician Augustin-Louis Cauchy, who originally defined it in 1830 in his article "The refraction and ...

  7. Chromatic aberration - Wikipedia

    en.wikipedia.org/wiki/Chromatic_aberration

    If the focal lengths of the two lenses for light at the yellow Fraunhofer D-line (589.2 nm) are f 1 and f 2, then best correction occurs for the condition: f 1 ⋅ V 1 + f 2 ⋅ V 2 = 0 {\displaystyle f_{1}\cdot V_{1}+f_{2}\cdot V_{2}=0}

  8. Dispersion (optics) - Wikipedia

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

    Dispersion (optics) In a dispersive prism, material dispersion (a wavelength -dependent refractive index) causes different colors to refract at different angles, splitting white light into a spectrum. In optics and in wave propagation in general, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency; [1 ...

  9. Lens - Wikipedia

    en.wikipedia.org/wiki/Lens

    A burning apparatus consisting of two biconvex lens. A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction.A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis.

  10. Dispersion relation - Wikipedia

    en.wikipedia.org/wiki/Dispersion_relation

    In a prism, dispersion causes different colors to refract at different angles, splitting white light into a rainbow of colors. In the physical sciences and electrical engineering , dispersion relations describe the effect of dispersion on the properties of waves in a medium.

  11. Perturbation theory (quantum mechanics) - Wikipedia

    en.wikipedia.org/wiki/Perturbation_theory...

    Assuming also that the degeneracy is completely lifted to the first order, i.e. that () if , we have the following formulae for the energy correction to the second order in