1. Waves, Light & Quanta Tim Freegarde
Web Gallery of Art; National Gallery, London

2. Young’s double slit diffraction x
amplitude
intensity

3. Single slit diffraction
amplitude x
intensity

4. Diffraction grating x place secondary sources along wavefront
...and trigger when wavefront arrives
apply to sinusoidal waves by taking into account the phase with which components arrive
INTERFERENCE
combine by adding the amplitudes
contributions may therefore interfere constructively or destructively

5. Grating spectrometer
scope.pari.edu

6. Michelson interferometerδx
interference by division of amplitude
beamsplitter
detector
source 6 6

7. Michelson interferometerδx δx
interference by division of amplitude
beamsplitter
detector
source 7 7

8. Michelson interferometerδx δx
interference by division of amplitude
beamsplitter
detector
FTIR: Fourier transform infrared
source
chemistry.oregonstate.edu
optique-ingenieur.org
sodium doublet

9. Newton’s rings beam-splitter diffuser lens plate
diffuser
lens
plate
apply to sinusoidal waves by taking into account the phase with which components arrive
combine by adding the amplitudes
contributions may therefore interfere constructively or destructively

10. Michelson stellar interferometer x
intensity

11. Michelson stellar interferometer   

12. Michelson stellar interferometer
Mount Wilson Observatory

13. Coherence NON-POINT OBJECTS
many independent emitters, e.g. different atoms in star
spatial extent (angular width) determines fringe visibility
partial visibility when phase difference partially defined
coherence is a measure of extent to which the phase difference is known
degree of coherence
(approximate expression – requires complex numbers)
complex degree of coherence

14. Light and optics RAYS straight propagation paths
least time (Fermat’s principle)
focus
reflection, refraction, lenses, telescopes, microscopes
directrix
WAVES
Huygens’ description of propagation, reflection, refraction
polarization, colour (wavelength, frequency)
diffraction, interference, beats, interferometers
Maxwell’s electromagnetism, Einstein’s relativity
PHOTONS
Planck, Compton, Einstein