1. Textbook: Optics (3 rd or 4 th Ed.), Eugene Hecht 光学（改编版）高等教育出版社 Reference: Principles of Optics, M. Born & E. Wolf 物理光学，梁铨廷，电子工业出版社 光学 OPTICS 叶 贤 基 教授 yexianji@mail.hust.edu.cn Phone: 87558393

2. Assessment Homework (20-30%) A few for each chapter Only partial marks if submitting after due date Final exam (80-70%) Closed-book 2.5 hours 1 brief-explanation and/or 5-6 calculation questions

3. What is light? Particle? or Wave?

4. Inspired by The History of Optics

5. Illustrations of various optical instruments from the 1728 Cyclopedia Modern optics laboratory

6. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

7. Pierre de Fermat Fields: Mathematics and Law Known for: Analytic geometry Probability Fermat's Last Theorem (Singh, Simon (2002). Fermat's Last Theorem. Fourth Estate Ltd.) Fermat's principle is the principle that the path taken between two points by a ray of light is the path that can be traversed in the least time. This principle is sometimes taken as the definition of a ray of light. Fermat's principle of least time was the first variational principle enunciated in physics. In this way, Fermat is recognized as a key figure in the historical development of the fundamental principle of least action in physics.

8. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

9. Isaac Newton Fields: physics, mathematics, astronomy Known for: Newtonian mechanics, Universal gravitation, Calculus, Optics From 1670 to 1672, Newton lectured on optics. During this period he investigated the refraction of light. He observed that colour is the result of objects interacting with already-coloured light rather than objects generating the colour themselves. The first known functional reflecting telescope, today known as a Newtonian telescope. Using Newton's rings to judge the quality of the optics for his telescopes. In his Hypothesis of Light of 1675, Newton posited the existence of the ether to transmit forces between particles. The contact with the theosophist Henry More, revived his interest in alchemy. He replaced the ether with occult forces based on Hermetic ideas of attraction and repulsion between particles. In 1704 Newton published Opticks. He considered light to be made up of extremely subtle corpuscles, that ordinary matter was made of grosser corpuscles.

10. Elements of the Philosophy of Newton is a book written by the philosopher Voltaire in 1738 that helped to popularize the theories and thought of Isaac Newton. Chapter 1What Light is, and in What manner it comes to us. Chapter 2The Property, which Light has of reflecting itself, was not truly known. It is not reflected by the solid Parts of Bodies as vulgarly believed. Chapter 3Of the property which Light has of refracting in passing from one Substance into another, and of taking a new Course in its Progression. Chapter 4Of the Form of the Eye, and in what manner Light enters and acts in that Organ. Chapter 5Of Looking–Glasses, and Telescopes: Reasons given by Mathematicians for the Mysteries of Vision; that those Reasons are not altogether sufficient. Chapter 6In what Manner we know Distances, Magnitudes, Figures, and Situations. Chapter 7Of the Cause of the breaking of the Rays of Light in passing from one Medium to another; that this Cause is a general Law of Nature unknown before Newton; that the Inflection of Light is also an Effect of the same Cause. Chapter 8The wonderful Effects of the Refraction of Light. The several Rays of Light have all possible Colours in themselves; what Refrangibility is. New Discoveries. Chapter 9The Cause of Refrangibility; from which it appears that there are indivisible Bodies in Nature. Chapter 10Proof that there are indivisible Atoms, and that the simple Particles of Light are Atoms of that kind. Discoveries continued. Chapter 11Of the Rainbow; that Phenomenon a necessary Effect of the Laws of Refrangibility. Chapter 12New Discoveries touching the Cause of Colours, which confirm the preceding Doctrine; Demonstration that Colours are occasioned by the Density and Thickness of the Parts of which Bodies are composed (or the Thickness of the Parts that compose the Surfaces only). Chapter 13Consequences of these Discoveries. The mutual Action of Bodies upon Light. Chapter 14Of the Resemblance between the seven Primitive Colours and the seven Notes in Musick. Chapter 15Introductory Ideas concerning Gravity and the Laws of Attraction. … Chapter 25Of the second Inequalities of the Motion of the Satellites, and the Phaenomena that depend thereon.

11. Opticks is largely a record of experiments and the deductions made from them. This work is not focused only on geometrical optics, but also covering a wide range of topics in what was later to be known as physical optics. In this book Newton sets forth in full his experiments. His experiments on these subjects and on the problems of diffraction (which he never fully mastered) set the subject of optics on a new level. Opticks and the Principia Opticks differs in many aspects from the Principia. (1) Unlike the Principia, Opticks is not presented in a strictly geometric form, with propositions proved by mathematics from either previous propositions or lemmas or first principles (or axioms). It does not prove its propositions by the use of ratios or equations, or by the tools of mathematics. Rather, the proofs generally proceed "by Experiments." Other scientists followed Newton's lead. They saw that he had been setting forth a kind of exploratory natural philosophy in which the primary source of knowledge was experiment. This Newtonian tradition of experimental natural philosophy was different from the one based on mathematical deductions. Regarding Newton’s “Opticks”

12. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

13. Thomas Young Fields: Physics, Physiology, Egyptology Young established himself as a physician in London, so as Young published many of his first academic articles anonymously to protect his reputation as a physician. Wave theory of light In the early 1800s Young put forth a number of theoretical reasons supporting the wave theory of light, he must overcome the century-old view, expressed in the venerable Isaac Newton's "Optics", that light is a particle. Young's modulus Young described the characterization of elasticity that came to be known as Young's modulus, in 1807. Barr, E. Scott (1963). "Men and Milestones in Optics. II. Thomas Young". Applied Optics 2: 639-647. Robinson, Andrew (April 2006). "Thomas Young: The Man Who Knew Everything". History Today 56: 53-57.

14. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

15. Augustin-Jean Fresnel Fields: Physics Known for: wave optics His discoveries and mathematical deductions, building on experimental work by Thomas Young, extended the wave theory of light to a large class of optical phenomena. In 1818 Poisson deduced from Fresnel's theory the necessity of a bright spot at the centre of the shadow of a circular opaque obstacle. With his counterintuitive result, Poisson hoped to disprove the wave theory; however Dominique Arago experimentally verifed the prediction. The existence of the spot had previously been observed in 1723 by Giacomo F. Maraldi, but the work had been largely unrecognized. Fresnel wrote to Young in 1824: in himself “that sensibility, or that vanity, which people call love of glory, had been blunted.” … “All the compliments that I have received from Arago, Laplace and Biot never gave me so much pleasure as the discovery of a theoretic truth, or the confirmation of a calculation by experiment.”

16. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

17. James Clerk Maxwell Fields: Physics and Mathematics Known for: Maxwell's equations Maxwell distribution Maxwell material Around 1862, Maxwell calculated that the speed of propagation of an electromagnetic field is approximately that of the speed of light. He considered this to be more than just a coincidence. His famous equations, in their modern form of four partial differential equations, first appeared in his textbook “A Treatise on Electricity and Magnetism” in 1873. In 1866, he formulated statistically, independently of Boltzmann, the Maxwell– Boltzmann kinetic theory of gases. His formula, called the Maxwell distribution, gives the fraction of gas molecules moving at a specified velocity at any given temperature. Maxwell published a famous paper "On governors" in the Proceedings of Royal Society, vol. 16. This paper is quite frequently considered a classical paper of the early days of control theory.

18. Timeline of Optics ~ 400 BC Aristophanes Lens, glass … ~ 300 BC Euclid The first to write about reflection and refraction 130 C. Ptolemy In his work “Optics”: Reflection, refraction, color and tabulated angle of refraction 1611 J. Kepler How the light focuses light Laws of the rectilinear propagation of light Discover total internal reflection 1621 Willebrord Snellius Snell’s law 1657 Pierre Fermat Principle of least time 1704 Isaac Newton Opticks 1676 O. Roemer Measure the speed of light by observing Jupiter’s moon 1678 C. Hyugens Principle of wavefront sources 1746 L. Euler Wave theory of light refraction and dispersion 1873 J.C. Maxwell Light = e.m. wave 1801 Thomas Young Young’s exp. (wave nature of light, and interference) 1818 A.-J. Fresnel Diffraction of light wave Polarization (transverse wave) 1818 Simeon Poisson Poisson-Arago bright spot 1700180019001600 1862 Leon Foucault c=2.98  10 8 m/s

19. Timeline of Optics 1873 J.C. Maxwell Light = e.m. wave 190020001800 1879 A.A. Michelson Interferometer C=299,910  50km/s … C=299,774  11km/s 1905 A. Einstein Special relativity 1905 A. Einstein Photoelectric effect 1900 Max Planck Black body radiation 1953 C.H. Townes MASER 1960 T Maiman LASER Nonlinear optics Quantum optics Quantum informatics Quantum manipulation Quantum measurement Atom optics Space interferometry

20. Various aspects of the nature of light Thomas Kuhn, The structure of scientific revolutions “Paradigm”

21. Thomas Kuhn, The structure of scientific revolutions “Paradigm”

22. What are you looking at?

23. A Paradigm is...? Kuhn baptizes his famous notion of a scientific "paradigm" as originating from the "great works" of science, like Newton’s Principia. These great works became paradigms because they were sufficiently unprecedented to attract an enduring group of adherents away from competing modes of scientific activity. Discoveries are Rare Because Expectations Obscure our Vision. No Paradigm Change without Crisis. New Paradigms Place New Relations Amongst the Data. Science is Non-Cumulative Because Terms Change their Meanings. Paradigms Transform Scientists’ View of the World. Some key points of Kuhn’s “The Structure of Scientific Revolutions”

24. The development of science doesn’t follow the logic and sequence of the textbooks. Experiments is not only the primary source of knowledge but also the final judgment of a theory. Existence of various courses is a convenient way for teaching and learning, but nature is a complete reality that cannot be separated into pieces. That is, you must learn the connections among these courses and build up the structure beyond physical theories by yourself. Challenge authority (e.g. professors). Be the host of yourself (active & responsible)

25. Unique Properties of Laser Light High monochromaticity (treating as a single-frequency wave) High degree of both spatial and temporal coherence (strong correlation in phase) High directionality (small beam divergence) Frequency/Intensity Stabilized He-Ne Laser High Power Nd:glass Laser

26. Laser Machining & Manufacturing 40  m square holes drilled in human hair with an ArF excimer laser A medical stent micromachined from a biodegradable polymer using a femtosecond laser Laser cutting

27. Optical Tweezer and Laser Cooling

28. Gravitational Waves Detection The Laser Interferometer Space Antenna (LISA)

29. Wave’s aspect (Physical optics, wave optics) reflectionrefraction scattering Particle’s aspect (Geometrical optics) diffractioninterference Classical Optics at a First Glance

30. Schedule Chap. 1 Introduction& Light (2 hours) A brief history Chap. 2 Electromagnetic Theory & Light (6 hours) Harmonic waves Maxwell’s equations Photon energy & momentum Light in bulk matter

31. Schedule Chap. 3 The propagation of Light (6 hours) Scattering, reflection & refraction Snell’s law & Fresnel’s equations Total internal reflection Chap. 6 The Superposition of Waves (4 hours) Fourier series Coherence time & coherence length Chap. 9 Polarization (10 hours) Polarized light Scattering & polarization Reflection & polarization Polarizers, retarders, optical modulators

32. Schedule Chap. 7 Interference (10 hours) Required conditions Wavefront-splitting interferometers Amplitude-splitting interferometers Types of interference fringes Multi-beam interference Applications of interferometry Chap. 8 Diffraction (8 hours) Fraunhofer diffraction Fresnel diffraction Kirchhoff’s scalar diffraction theory