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

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Space

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Space

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Frequency

Inte

nsity

Space

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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

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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