Optics

114 Pages·2000·12.006 MB·English

by  Benjamin Crowell

Book 5 in the Light and Matter series of free introductory physics textbooks
www.lightandmatter.com

The Light and Matter series of
introductory physics textbooks:
1 Newtonian Physics
2 Conservation Laws
3 Vibrations and Waves
4 Electricity and Magnetism
5 Optics
6 The Modern Revolution in Physics
Benjamin Crowell
www.lightandmatter.com
Fullerton, California
www.lightandmatter.com
copyright 1999-2006 Benjamin Crowell
edition 2.2
rev. September 1, 2007
This book is licensed under the Creative Com-
mons Attribution-ShareAlike license, version 1.0,
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for those photographs and drawings of which I am not
the author, as listed in the photo credits. If you agree
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copy this book under the GNU Free Documentation
License version 1.2, http://www.gnu.org/licenses/fdl.txt,
with no invariant sections, no front-cover texts, and no
back-cover texts.
ISBN 0-9704670-5-2
Brief Contents
1 The Ray Model of Light 11
2 Images by Reflection 31
3 Images, Quantitatively 43
4 Refraction 59
5 Wave Optics 77
Contents
Problems . . . . . . . . . . . . . 41
1 The Ray Model of Light
1.1 The Nature of Light . . . . . . . 12
Thecauseandeffectrelationshipinvision,
3 Images, Quantitatively
12.—Light is a thing, and it travels from
onepointtoanother.,13.—Lightcantravel 3.1 A Real Image Formed by a Converg-
through a vacuum., 14. ing Mirror . . . . . . . . . . . . . 44
1.2 Interaction of Light with Matter. . . 15 Locationoftheimage,44.—Magnification,
Absorption of light, 15.—How we see non- 47.
luminous objects, 15.—Numerical mea- 3.2 Other Cases With Curved Mirrors . 47
surement of the brightness of light, 17.
3.3 ? Aberrations. . . . . . . . . . 52
1.3 The Ray Model of Light . . . . . 18
Summary . . . . . . . . . . . . . 54
Models of light, 18.—Ray diagrams, 19.
Problems . . . . . . . . . . . . . 56
1.4 Geometry of Specular Reflection . 22
Reversibility of light rays, 23.
1.5 ? The Principle of Least Time for
Reflection . . . . . . . . . . . . . 25
Summary . . . . . . . . . . . . . 27
Problems . . . . . . . . . . . . . 28
4 Refraction
4.1 Refraction . . . . . . . . . . . 60
Refraction, 60.—Refractive properties of
media, 61.—Snell’s law, 62.—The index
of refraction is related to the speed of
2 Images by Reflection light., 63.—A mechanical model of Snell’s
law,64.—AderivationofSnell’slaw,64.—
2.1 A Virtual Image . . . . . . . . . 32
Color andrefraction, 65.—How much light
2.2 Curved Mirrors . . . . . . . . . 34 isreflected,andhowmuchistransmitted?,
2.3 A Real Image. . . . . . . . . . 35 65.
2.4 Images of Images . . . . . . . . 36 4.2 Lenses . . . . . . . . . . . . 68
Summary . . . . . . . . . . . . . 40 4.3 ? The Lensmaker’s Equation . . . 70
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4.4 ? The Principle of Least Time for 5.5 Double-Slit Diffraction . . . . . . 82
Refraction . . . . . . . . . . . . . 70 5.6 Repetition . . . . . . . . . . . 86
Summary . . . . . . . . . . . . . 71 5.7 Single-Slit Diffraction . . . . . . 87
R
Problems . . . . . . . . . . . . . 72 5.8 ? The Principle of Least Time . . 89
Summary . . . . . . . . . . . . . 91
Problems . . . . . . . . . . . . . 93
5 Wave Optics
5.1 Diffraction . . . . . . . . . . . 78
5.2 Scaling of Diffraction. . . . . . . 79 Appendix 1: Exercises 97
5.3 The Correspondence Principle . . 80 Appendix 2: Photo Credits 105
5.4 Huygens’ Principle . . . . . . . 81 Appendix 3: Hints and Solutions 106
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