Calculating Particle Spacing in a Lattice Using Fourier Transform

[indie452]

Homework Statement

Okay so i am applying a FT to an image of particles that are forming a lattice, and i need to find the average distance between the particles

because its not a perfect lattice, I am getting an airy pattern and i believe that the distance to the first ring is the average distance between the particle.

But, i don't know how to convert reciprocal space pixel size into normal space.
I believe i need to use the 2pi/d where d is the spacing between 2 particles, but i don't know how many pixels are in 2pi/d

note: i know the scale of my image width and height in pixels and microns

 

[marcusl]

An Airy disk results from transforming a circular disk. Are your particles contained within a disk? You may be looking at the envelope.

Is your lattice regular (e.g., rectangular, triangular, etc.)? If so, then you can find the spacing from the location of aliases, that is, replications of the primary Airy disk.