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Wave Optics Propagation, interference and diffraction of waves Axel Kuhn, Oxford 2016 Paul Ewart’s lecture notes and problem sets: https://www2.physics.ox.ac.uk/research/ combustion-physics-and-non-linear-optics/teaching Intro Brooker, Modern Classical Optics Hecht, Optics Klein and Furtak, Optics Smith, King & Wilkins, Optics and Photonics Born and Wolf, Principles of Optics Wave Optics – Literature Intro Wave Optics – Outline What’s it all about? Revision of geometrical optics Propagation of waves Fourier methods Fresnel-Kirchhoff integral, theory of imaging Diffraction-based optical instruments 2-slit, grating, Michelson and Fabry-Perot Interferometer Dielectric surfaces and boundaries multilayer (anti)reflection coatings Polarized Light Intro What’s it all about? Imaging Visualization (projection, lithography) Spectroscopy Matter-wave propagation & imaging Lasers and applications Modern devices (opto-electronics, display technology, optical coatings, telecommunication, consumer electronics) Intro

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Wave Optics Propagation, interference and diffraction of waves

Axel Kuhn, Oxford 2016

Paul Ewart’s lecture notes and problem sets:

https://www2.physics.ox.ac.uk/research/combustion-physics-and-non-linear-optics/teaching

Intro

Brooker, Modern Classical Optics Hecht, OpticsKlein and Furtak, OpticsSmith, King & Wilkins, Optics and PhotonicsBorn and Wolf, Principles of Optics

Wave Optics – Literature

Intro

Wave Optics – Outline

What’s it all about?Revision of geometrical opticsPropagation of waves Fourier methods

➙ Fresnel-Kirchhoff integral, theory of imaging

Diffraction-based optical instruments ➙ 2-slit, grating, Michelson and Fabry-Perot Interferometer

Dielectric surfaces and boundaries ➙ multilayer (anti)reflection coatings

Polarized Light

Intro

What’s it all about?

Imaging Visualization (projection, lithography)SpectroscopyMatter-wave propagation & imagingLasers and applicationsModern devices(opto-electronics, display technology, optical coatings, telecommunication, consumer electronics)

Intro

Astronomical observatory, Hawaii, 4200m above sea level.

What’s it all about?

Intro

Hubble space telescope, 2.4 m mirror

What’s it all about?

Intro

Classical Optics – Relevance

Optical Microscopefru

it fly

What’s it all about?

Intro

CD/DVD player optical pickup system

What’s it all about?

Intro

What’s it all about?

photo lithography

cutting & welding

Intro

Coherent Light ➙ Laser Physics

spectroscopymetrology (clocks)quantum opticsquantum computinglaser nuclear ignitionmedical applicationsengineeringtelecommunication

What’s it all about?

Intro

Geometrical Optics – Revision

Fermat’s principle (shortest path)reflection & refractionspherical & thin lensesparaxial approximationlensmaker’s formulacombining lensesprincipal planesoptical instrumentsAperture and field stopsPinhole camera ➙ wave optics

Geometric

Fermat‘s PrincipleLight propagating between two points follows a path, or paths, for which the time taken is an extremum (minimum)

Ignoring the wave nature of lightBasic theory for optical instruments

Geometrical Optics – Revision

Geometric

focussing with spherical surfaces

parallel bundles↓

image sphere

object sphere↓

image sphere

Geometrical Optics – Revision

Geometric

axis

Focal point

Focal point

u v

thin lens formula

Geometrical Optics – Revision

1u

+1v

=1f

Geometric

location of equivalent thin lens

Geometrical Optics – Instruments

Prin

cipa

l pla

nes

Geometric

location of equivalent thin lens

Prin

cipa

l pla

nes

Geometrical Optics – Instruments

Geometric

u v

lenssystem

1u

+1v

=1f

thin lens equation applies with u and vmeasured from the two principal planes

Geometrical Optics – Instruments

Prin

cipa

l pla

nes

Geometric

Objective magnification = v/u Eyepiece magnifies real image of object

Com

poun

d m

icro

scop

e

Geometrical Optics – Instruments

Geometric

angular magnification = β/α = fo/fE

Astro

nom

ical

tele

scop

e

Geometrical Optics – Instruments

Geometric

angular magnification = β/α = fo/fE

1.3.4 Telescope (Galilean)

!"!#

!

!Figure 1.6

"#$%&'(!)'$#*+*,'-*.#/!! $ " !!" " ! %!!# !!!

1.3.5 Telescope (Newtonian)

!

!%

!#

!Figure 1.7

"#$%&'(!)'$#*+*,'-*.#/!! $ " !!" " ! %!!# !!

! ! % !!*0!-12!+.,'&!&2#$-1!.+!-12!.342,-*52!)*((.(!'#6!7+.(!'!0812(*,'&!)*((.(!0%(+',29!2:%'&0!

1'&+!-12!('6*%0!.+!,%(5'-%(2;!

!

1.3.6 Compound Microscope

!" !#

!

!"

!Figure 1.8

!

<12!.342,-!'-!6*0-'#,2!&!+(.)!.342,-*52!=*-1!+.,'&!&2#$-1!!%!*0!*)'$26!'-!6*0-'#,2!';!>2'&!

*)'$2!*0!'-!+.,'&!&2#$-1!!#!+(.)!2?28*2,2!$*5*#$!'#$%&'(!)'$#*+*,'-*.#(!#$%!=12(2!$!!*0!-12!'#$&2!0%3-2#626!3?!-12!(2'&!*)'$2!*+!*-!='0!'-!-12!#2'(!8.*#-!.+!-12!2?2;!

!

Gal

ilean

tele

scop

eGeometrical Optics – Instruments

Geometric

Field stop

Apertures and Field Stops

limiting thefield-of-view

Aperture stop

limiting theIntensity

f/no. =

focal leng

th

entran

ce pupil dia

meter

Geometric

Camera Obscura

optimum pinhole size

contradicts expectations from geometrical optics

from Hecht, Optics

Geometric

Maxwell’s equations ⟼ waves

equivalence to matter waves

plane and spherical waves

energy flow / intensity

Huygen’s principle

The Wave Nature of Light

EM waves

Maxwell’s Equations

~r · ~B = 0 ~r⇥ ~H =d

dt~D

~r · ~D = 0 ~r⇥ ~E = � d

dt~B

linear isotropic medium⇢ = 0 ~J = 0

~D = ✏r✏0 ~E~B = µrµ0

~H

r2 ~E =⇣nc

⌘2 d2

dt2~E and r2 ~H =

⇣nc

⌘2 d2

dt2~H

EM waves

Plane and Spherical Waves

plane wave

spherical wave

n =p ✏rµr

c = 1/p ✏0µ0

vp= c/n

= !/k= ⌫�

~S =~E ⇥ ~H

k =2⇡

�= nk0

EM waves

u → amplitude of E, H, ψ …(�+ k2)u = 0

u(~r, t) = u0ei(~k~r�!t)

u(~r, t) = u0ei(kr�!t)/r

Huygen’s Principle

Huygens’ wavelet ebcid:com.britannica.oec2.identifier.AssemblyIdentifier?assemblyId=...

1 of 1 23.11.2008 19:56 Uhr

Figure 2: Huygens' wavelets. Originating along the fronts of (A) circular waves and (B) plane waves, wavelets recombine to produce the propagating wave front. (C) The diffraction of sound around a corner

arising from Huygens' wavelets.

Huygens’ wavelet

print articles

Every point on a wave frontcan be considered as a sourceof secondary spherical waves

u(~R) /Z

u(~r)eik|

~R�~r|

|~R� ~r|dS

Huygens

Interference of Waves