Search results
Results From The WOW.Com Content Network
Subscripts 1 and 2 refer to initial and final optical media respectively. These ratios are sometimes also used, following simply from other definitions of refractive index, wave phase velocity, and the luminal speed equation:
But, for optically transparent media, and for all other materials at optical frequencies (except possible metamaterials), μ rel is indeed very close to 1; that is, μ ≈ μ 0. In optics, one usually knows the refractive index n of the medium, which is the ratio of the speed of light in vacuum (c) to the speed of light
The aim of an accurate intraocular lens power calculation is to provide an intraocular lens (IOL) that fits the specific needs and desires of the individual patient. The development of better instrumentation for measuring the eye's axial length (AL) and the use of more precise mathematical formulas to perform the appropriate calculations have significantly improved the accuracy with which the ...
In solid-state physics, the k·p perturbation theory is an approximated semi-empirical approach for calculating the band structure (particularly effective mass) and optical properties of crystalline solids. [1] [2] [3] It is pronounced "k dot p", and is also called the k·p method.
A perfect optical system produces an image with the same etendue as the source. The etendue is related to the Lagrange invariant and the optical invariant, which also share the property of being constant in an ideal optical system. The radiance of an optical system is equal to the derivative of the radiant flux with respect to the etendue.
An expression for n as a function of photon energy, symbolically written as n(E), is then determined from the expression for k(E) in accordance to the Kramers–Kronig relations [4] which states that n(E) is the Hilbert transform of k(E). The Forouhi–Bloomer dispersion equations for n(E) and k(E) of amorphous materials are given as:
In computer vision, the Lucas–Kanade method is a widely used differential method for optical flow estimation developed by Bruce D. Lucas and Takeo Kanade.It assumes that the flow is essentially constant in a local neighbourhood of the pixel under consideration, and solves the basic optical flow equations for all the pixels in that neighbourhood, by the least squares criterion.
The function () expresses the dispersion relation of the given medium. Dispersion relations are more commonly expressed in terms of the angular frequency ω = 2 π f {\displaystyle \omega =2\pi f} and wavenumber k = 2 π / λ {\displaystyle k=2\pi /\lambda } .