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  2. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    Prentice's rule, named so after the optician Charles F. Prentice, is a formula used to determine the amount of induced prism in a lens: = where: P is the amount of prism correction (in prism dioptres) c is decentration (the distance between the pupil centre and the lens's optical centre, in millimetres)

  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. Prism (optics) - Wikipedia

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

    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.

  5. Dioptre - Wikipedia

    en.wikipedia.org/wiki/Dioptre

    A dioptre ( British spelling) or diopter ( American spelling ), symbol dpt, is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dpt = 1 m−1. It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length ...

  6. 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 E n k = E n 0 + λ V n k , n k + λ 2 ∑ m ≠ n | V m , n k | 2 E n ( 0 ) − E m ( 0 ) + O ( λ 3 ) , {\displaystyle E_{nk}=E_{n}^{0}+\lambda V_{nk,nk}+\lambda ^{2}\sum ...

  7. 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.

  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. Geometrical optics - Wikipedia

    en.wikipedia.org/wiki/Geometrical_optics

    The first equation is known as the eikonal equation, which determines the eikonal is a Hamilton–Jacobi equation, written for example in Cartesian coordinates becomes ( ∂ S ∂ x ) 2 + ( ∂ S ∂ y ) 2 + ( ∂ S ∂ z ) 2 = n 2 . {\displaystyle \left({\frac {\partial S}{\partial x}}\right)^{2}+\left({\frac {\partial S}{\partial y}}\right ...

  11. List of equations in quantum mechanics - Wikipedia

    en.wikipedia.org/wiki/List_of_equations_in...

    Planck–Einstein equation and de Broglie wavelength relations. P = ( E/c, p) is the four-momentum, K = (ω/ c, k) is the four-wavevector, E = energy of particle. ω = 2π f is the angular frequency and frequency of the particle. ħ = h /2π are the Planck constants. c = speed of light. Schrödinger equation.