A Matlab simulation for a 4F Correlator system which is based on the Fourier transforming properties of lenses.
Aliaksei Petsiuk, 2019
The 4F Optical Correlator system is based on the Fourier transforming properties of lenses. According to the Diffraction theory, a convex lens of focal length f will produce the Fourier transform at a distance f behind the lens of an object placed at f distance in front of the lens. These properties give us an opportunity to implement direct and inverse Fourier transforms of two-dimensional objects and modify and analyze their spatial frequency spectra.
Figure 0. Model of the experiment
An input is a transparent image of a black letter "A". Matlab simulation was performed for the following filter parameters:
| Parameter | Value |
|---|---|
| Pinhole diameter | 255 microns |
| Band-pass filter | 500 microns/300 microns |
| Slit long side | 800 microns |
| Slits short side | 120 microns |
| Spacing between centers of the slits | 300 microns |
Figure 1. No Filter
Figure 2. Pinhole
Figure 3. Horizontal Single Slit
Figure 4. Horizontal Double Slit
Figure 5. Vertical Single Slit
Figure 6. Vertical Double Slit
Figure 7. Fresnel Zone
Figure 8. Mesh
Aliaksei Petsiuk, 2019
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