Ch35_Lecture_Notesb

# Ch35_Lecture_Notesb - 1 Chapter 35 The concept of optical...

This preview shows pages 1–8. Sign up to view the full content.

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

View Full Document

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

View Full Document

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

View Full Document

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.

Unformatted text preview: 1 Chapter 35 The concept of optical interference is critical to understanding many natural phenomena, ranging from color shifting in butterfly wings to intensity patterns formed by small apertures. These phenomena cannot be explained using simple geometrical optics, and are based on the wave nature of light. In this chapter we explore the wave nature of light and examine several key optical interference phenomena. Interference 35- 2 Huygen’s Principle: All points on a wavefront serve as point sources of spherical secondary wavelets. After time t , the new position of the wavefront will be that of a surface tangent to these secondary wavelets. Light as a Wave 35- Fig. 35-2 Animation 3 Law of Refraction 35- Index of Refraction: c n v = Fig. 35-3 1 2 1 1 1 2 2 2 v t v v v λ λ λ λ = = = 1 1 2 2 sin (for triangle hce) sin (for triangle hcg) hc hc λ θ λ θ = = 1 1 1 2 2 2 sin sin v v θ λ θ λ = = 1 2 1 2 and c c n n v v = = 1 1 2 2 2 1 sin sin c n n c n n θ θ = = Law of Refraction: 1 1 2 2 sin sin n n θ θ = 4 35- Checkpoint 1 Monochromatic light ray travels through layers of materials. In which materials does light travel slowest? i i c v n = In which materials does light travel fastest? 5 Wavelength and Index of Refraction 35- Fig. 35-4 n n n v v c c n λ λ λ λ λ λ =0 = = n n v c n c f f n λ λ λ = = = = The frequency of light in a medium is the same as it is in vacuum Since wavelengths in n 1 and n 2 are different, the two beams may no longer be in phase 1 1 1 1 1 Number of wavelengths in : n L L Ln n N n λ λ λ = = = 2 2 2 2 2 Number of wavelengths in : n L L Ln n N n λ λ λ = = = ( 29 2 1 2 1 2 1 2 1 Assuming : Ln Ln L n n N N n n λ λ λ- =- =- 2 1 1/2 wavelength destructive interference N N- = 6 The geometrical explanation of rainbows given in Ch. 34 is incomplete. Interference, constructive for some colors at certain angles, destructive for other colors at the same angles is an important component of rainbows Rainbows and Optical Interference 35- Fig. 35-5 7 35- Fig. 35-4 Checkpoint 2 Light waves of rays in Fig. 35-4 have same wavelength and amplitude and enter slabs in phase....
View Full Document

## This note was uploaded on 04/08/2008 for the course PHY 207 taught by Professor Berim during the Spring '08 term at SUNY Buffalo.

### Page1 / 27

Ch35_Lecture_Notesb - 1 Chapter 35 The concept of optical...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online