Search results
Results from the WOW.Com Content Network
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)
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.
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]
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 ...
The mathematical derivation for the Eötvös effect for motion along the Equator explains the factor 2 in the first term of the Eötvös correction formula. What remains to be explained is the cosine factor.
N = 1 μ 0 E × B = E × H {\displaystyle \mathbf {N} = {\frac {1} {\mu _ {0}}}\mathbf {E} \times \mathbf {B} =\mathbf {E} \times \mathbf {H} \,\!} Φ N = ∫ S N ⋅ d S {\displaystyle \Phi _ {N}=\int _ {S}\mathbf {N} \cdot \mathrm {d} \mathbf {S} \,\!}
The formula may appear simpler in terms of renamed simple values = / and =, avoiding any appearance of trig function names or angle names: v → r e f r a c t = r l → + ( r c − 1 − r 2 ( 1 − c 2 ) ) n → {\displaystyle {\vec {v}}_{\mathrm {refract} }=r{\vec {l}}+\left(rc-{\sqrt {1-r^{2}\left(1-c^{2}\right)}}\right){\vec {n}}}
Formula. In minimum deviation, the refracted ray in the prism is parallel to its base. In other words, the light ray is symmetrical about the axis of symmetry of the prism. [1] [2] [3] Also, the angles of refractions are equal i.e. r1 = r2. The angle of incidence and angle of emergence equal each other ( i = e ).
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.
The Prentice position is an orientation of a prism, used in optics, optometry and ophthalmology. 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 takes ...