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Prism dioptres. Prism correction is commonly specified in prism dioptres, a unit of angular measurement that is loosely related to the dioptre. Prism dioptres are represented by the Greek symbol delta (Δ) in superscript. A prism of power 1 Δ would produce 1 unit of displacement for an object held 100 units from the prism. [2]
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]
List of unsolved problems in physics. The following is a list of notable unsolved problems grouped into broad areas of physics. [1] Some of the major unsolved problems in physics are theoretical, meaning that existing theories seem incapable of explaining a certain observed phenomenon or experimental result. The others are experimental, meaning ...
Snell's law (also known as the Snell–Descartes law, the ibn-Sahl law, [1] and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.
List of equations in nuclear and particle physics; List of equations in quantum mechanics; List of equations in wave theory; List of relativistic equations; Sources. P.M. Whelan; M.J. Hodgeson (1978). Essential Principles of Physics (2nd ed.). John Murray. ISBN 0-7195-3382-1. G. Woan (2010). The Cambridge Handbook of Physics Formulas. Cambridge ...
Spherical aberration of collimated light incident on a concave spherical mirror. In optics, spherical aberration ( SA) is a type of aberration found in optical systems that have elements with spherical surfaces. This phenomenon commonly affects lenses and curved mirrors, as these components are often shaped in a spherical manner for ease of ...
Treatment options for esotropia include glasses to correct refractive errors (see accommodative esotropia below), the use of prisms, orthoptic exercises, or eye muscle surgery. The term is from Greek eso meaning "inward" and trope meaning "a turning".
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.
Aberration (astronomy) A diagram showing how the apparent position of a star viewed from the Earth can change depending on the Earth's velocity. The effect is typically much smaller than illustrated. In astronomy, aberration (also referred to as astronomical aberration, stellar aberration, or velocity aberration) is a phenomenon where celestial ...
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 ...