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Unformatted text preview: 28 Physics Formulary by ir. J.C.A. Wevers The dispersion of a prism is deFned by: D = d δ d λ = d δ dn dn d λ where the Frst factor depends on the shape and the second on the composition of the prism. ¡or the Frst factor follows: d δ dn = 2 sin( 1 2 α ) cos( 1 2 ( δ min + α )) ¡or visible light usually holds dn/d λ < : shorter wavelengths are stronger bent than longer. The refractive index in this area can usually be approximated by Cauchy’s formula. 6.8 Diffraction ¡raunhofer diffraction occurs far away from the source(s). The ¡raunhofer diffraction of light passing through multiple slits is described by: I ( θ ) I = sin( u ) u 2 · sin( Nv ) sin( v ) 2 where u = π b sin( θ ) / λ , v = π d sin( θ ) / λ . N is the number of slits, b the width of a slit and d the distance between the slits. The maxima in intensity are given by d sin( θ ) = k λ . The diffraction through a spherical aperture with radius a is described by: I ( θ ) I = J 1 ( ka sin( θ )) ka sin( θ...
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This note was uploaded on 11/16/2010 for the course ENGR 201 taught by Professor Elder during the Spring '10 term at Blinn College.
- Spring '10