imaging with waves. how good is the eye? 100 - 50 m resolution
Post on 22-Dec-2015
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The diffraction limit
Objects spaced apart by less than d~/2NA cannot be resolved individually!
Ernst Abbe (1840-1905)
Imaging with the diffraction limit
Object ImageFocal spot
Images can be improved by using shorter wavelengths
CD versus DVD
7x more data on DVD because of different wavelength!
780 nm 650 nm
(Blu-Ray DVD uses 405 nm, 6x more data than DVD)
Seeing smaller thingsusing EM radiation using particles
of particles:
€
= hmv
Electron with v = 1.0 x 105 m/s:
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=6.626 ×10−34 Js
9.11×10−31kg( ) 1.0 ×105m /s( )
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€
=7.3×10−9m
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=7.3nm
What are X -rays?
Wilhelm Conrad Röntgen (1845-1923)
Electromagnetic radiation with wavelength of ~10-10 m