PHY2049ch34B%284-9-10%290

PHY2049ch34B%284-9-10%290 - Thin Lenses Last time we...

This preview shows pages 1–6. Sign up to view the full content.

Thin Lenses Last time we considered image formation by a single spherical surface where the light rays are refracted (deviated) upon crossing the (spherical) interface. i θ r θ i r p 1 n 2 n 12 2 1 nn p ir += O If O faces ( r is + If O faces ) r is -

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
It is the deviation of the rays on refraction through the surface (in accord with Snell’s law) that causes the convergence or divergence of the rays that leads to image formation. r p 12 nn = If there is no change in refractive index no image can form.
Two spherical refracting surfaces of the same index of refraction, n , merged into one, make up a lens, which refracts at each interface. We consider two types: n Converging lens (object rays converge) Diverging lens (object rays diverge) nn > >

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
With T the thickest part of the lens if: 12 1n 1 1 1 fn r r ⎛⎞ =− ⎜⎟ ⎝⎠ T r,r ,p&i << The lens is a thin lens & obeys the lens maker’s formula: r 1 radius of side nearer object r 2 opposite side. Converging: + r 1 , – r 2 Diverging: – r 1 , + r 2 + f f n : refractive index of lens : refractive index of medium ( 1 for air) n signs: (real) (virtual)
11 1 p if += i m p =−

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/23/2010 for the course PHY 2049 taught by Professor Any during the Spring '08 term at University of Florida.

Page1 / 16

PHY2049ch34B%284-9-10%290 - Thin Lenses Last time we...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online