Lecture 16 Prisms EXAM Next week. Prism Angles

Lecture 16

Prisms

EXAM Next week

Prism2

2

2 2

/) / (

)( 1 )

(e

o

o o

qE tn

N m

ò òò

Angles

Minimum Deviation

At minimum deviation, the ray travels parallel to the base

\2 \2

2 2i t

2 t

sin2 2

m nsin

Real Example

Prism spectrometer

Resolving Power

Recall OPL=ns F

T

W

G BFT TW nb b

F W

G Bb

( )s n bFT TW n

s b n

Resolving Power cont

b

s b n

ddns b

d

sd

Rayleigh Criterion

d

/ )()( min b dn d

Resolving power: ( )min

dnbd

Example

What is the resolving power and minimum resolvable wavelengthDifference for a prism made of flint glass with a base of 5cm?

4 11.19 10n

x nm

( )min

dnbd

@550nm

Other prism types

Pellin-BrocaAbbe

Reflecting prisms

Right Angle

Dove

Penta