Rotating objects tend to keep rotating while non-rotating objects tend to remain non-rotating.
Rotating Beams
description
Transcript of Rotating Beams
![Page 1: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/1.jpg)
Dept. Elect. Eng.Technion – Israel Institute of Technology
Rotating Beams
Yoav Y. Schechner
1
Joint studies with J. Shamir, R. Piestun, A. Greengard
![Page 2: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/2.jpg)
Yoav Schechner
Waves having a Phase Dislocation
propagation direction
a helical wavefront
![Page 3: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/3.jpg)
Yoav Schechner
propagation direction
helical wavefront surface
local k-vectors (normals to the wavefront surface) have azimuthal
component
local k-vectors
orbital angular
momentum in the
wave
k vector : momentu
m
Waves having a Phase Dislocation
![Page 4: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/4.jpg)
Schechner & Shamir
propagation direction
Isotropic dislocation: helical
wavefront
propagation directionAnisotropic dislocation
Parameterizations
Morphological:• Stretch angle
• Eccentricity
• Dark fringe: a limit of eccentricity
Physical:
• Superposition of
isotropic waves • Dark fringe:
annihilation of isotropic dislocations
• Angular momentum
Anisotropic Dislocations
![Page 5: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/5.jpg)
Rotating PSF
Schechner
![Page 6: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/6.jpg)
Schechner et. al, Physical Review E 1996
Computer-Generated Hologram
(Diffractive Optical Element)
![Page 7: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/7.jpg)
Utopian Geometric PSF
Width changes linearly with z
z
Yoav Schechner
![Page 8: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/8.jpg)
Standard PSF
Width changes with z
…by just a 2nd order
z
![Page 9: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/9.jpg)
Rotating PSF
Standard PSF
Greengard, Schechner, Piestun
![Page 10: Rotating Beams](https://reader036.fdocuments.in/reader036/viewer/2022062518/56814230550346895dae4813/html5/thumbnails/10.jpg)
Greengard, Schechner, Piestun: Depth from diffracted rotation