All Optical Image Processing with the 4-f system
Kieran Metcalf BSc Ex
4-f Optical System
Equipment Set Up
f f f f
What is Spatial Frequency?
Representing the Fourier Components in Frequency Space
Space
Inte
nsi
ty
Space
Inte
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ty
Space
Inte
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ty
Frequency
Inte
nsity
Space
Inte
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ty
The spatial frequency plot is THE SAME as the image formed between the two lenses
f f f f
35mm Slide
The Physical Laws of the Diffraction Grating
sina
nm8.632
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Line Seperation / mm
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How the Image information is stored in the Fourier Transform
Spatial Frequency
How the Image information is stored in the Fourier Transform
Multiple Frequencies
How the Image information is stored in the Fourier Transform
Orientation
Filtering Out the Frequencies
References
• http://enteos2.area.trieste.it/russo/LabInfoMM2005-2006/ProgrammaEMaterialeDidattico/daStudiare/009-FourierInSpace.html
• http://www.physics.uq.edu.au/people/mcintyre/applets/grating/grating.html
• Eugene Hecht OPTICS Fourth Edition 13.2 Imagery – The Spatial Distribution of Optical Information
• http://enteos2.area.trieste.it/russo/LabInfoMM2005-2006/ProgrammaEMaterialeDidattico/daStudiare/009-FourierInSpace.html
• http://www.physics.uq.edu.au/people/mcintyre/applets/grating/grating.html
• Eugene Hecht OPTICS Fourth Edition 13.2 Imagery – The Spatial Distribution of Optical Information
