1 / 17

PC20312 Wave Optics

PC20312 Wave Optics. Section 2: Polarization. Polarization states. linear. circular. elliptical. Image from Wikipedia. Linear and circular polarization. http://physics-animations.com/Physics/AVI/ellf.avi. Dipole radiation. E. Optical E-field….

bewers
Download Presentation

PC20312 Wave Optics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PC20312 Wave Optics Section 2: Polarization

  2. Polarization states linear circular elliptical Image from Wikipedia

  3. Linear and circular polarization http://physics-animations.com/Physics/AVI/ellf.avi

  4. Dipole radiation E Optical E-field… …drives oscillating dipoles in the medium… …which radiate in all directions except parallel to E. http://www-antenna.ee.titech.ac.jp /~hira/hobby/edu/em/dipole2/dipole2.html http://physics.usask.ca/~hirose/ep225/radiation.htm www.harvard.edu/~efortin/thesis/html/EMR_light.shtml

  5. Ei Er Er Ei Et Et Polarization by reflection Click here for a web-based animation of Brewster’s angle • E parallel to plane of incidence • “p-polarised” • Emission amplitude varies with direction of Er • E perpendicular to plane of incidence • “s-polarised” • Emission always max in direction of Er

  6. Brewster’s angle, B P-polarised light Ei Er=0 B ni t nt Et Sir David Brewster 1781-1868

  7. Polarization by scattering Ein vertical  no vertical scattering Ein horiz.  no horiz. scattering polarised For unpolarised incident light the scattered light is: Completely polarised in vertical  horiz directions Partially polarised in intermediate directions partially polarised unpolarised Animation from http://www-antenna.ee.titech.ac.jp/~hira/hobby/edu/em/smalldipole/force.gif

  8. Polarized light in nature Unfiltered image Image seen through polarising filter Image from Wikipedia

  9. Polaroid E-field component aligned with long axis of molecule is absorbed E  E cos E sin E cos Polaroid sheet eg aligned PVA molecules PVA structure from http://wwwchem.csustan.edu/CHEM2000/EXP2/bkg.htm

  10. Malus’ Law Etienne-Louis Malus 1775-1812 http://physics-animations.com/Physics/AVI/polariz.avi

  11. Anisotropic Materials Ey Ex Py Px For calcite: Calcite CaCO3 no = 1.658 & ne=1.486 (at =590 nm) Image from Wikipedia

  12. Eo Eo Ee Birefringence Optic Axis z k  • Eo perpendicular to k & optic axis • Eeperpendicular to Eo  y x

  13. Double Refraction Optic Axis e-ray unpolarised light o-ray For calcite, typical angle between beams ~6 Image from Wikipedia

  14. Polarizing Beamsplitter calcite unpolarised light polarised light e-ray o-ray transparent glue polarised light Optic Axis points towards you Photo from http://www.lightmachinery.com

  15. Waveplates Optic Axis z no>ne : Optic Axis is ‘fast’ ne>no : Optic Axis is ‘slow’ y x d In this diagram, is the optic axis slow or fast? Photo from http://www.lightmachinery.com

  16. The Faraday Effect Image from http://en.wikipedia.org/wiki/Faraday_effect

  17. E P1 P1 45 45 B B P2 P2 Faraday Isolator E

More Related