apetsiuk / 4f-optical-correlator-simulation

A Matlab simulation for a 4F Correlator system which is based on the Fourier transforming properties of lenses.

4F Optical Correlator Simulation

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

Matlab Setup

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

Simulation Results

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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