# A study of the effects of Gaussian distribution of coherence length of   source on the diffraction of partial temporal coherence beam from multi   slits: Theory and simulation

**Authors:** E. Koushki, S. A. Alavi

arXiv: 1906.01330 · 2023-10-20

## TL;DR

This paper extends the theory of diffraction of partially coherent light through multiple slits to include Gaussian-distributed coherence lengths, analyzing how coherence affects diffraction patterns through simulations.

## Contribution

It generalizes the diffraction theory to arbitrary multi-slits with variable coherence lengths modeled by a Gaussian distribution, incorporating decoherence effects.

## Key findings

- Decoherence parameter ≥ 1 causes significant diffraction pattern changes.
- Results align with previous perfect coherence studies as coherence length approaches infinity.
- Gaussian distribution of coherence length influences far-field diffraction patterns.

## Abstract

First, we have generalized the notion of Franhoufer diffraction of temporal coherent light from a single slit to the case of arbitrary n-slits. The diffraction pattern is investigated for different values of recently [19] introduced parameter, decoherence parameter. It is shown that for multi-slits, the temporal decoherence effects appear for the values of decoherence parameter equal or bigger than 1 namely the coherence length is shorter that the size of the slits. Results of our study reproduce the previous studies for perfect temporal case, when coherence length tends to infinity. Then to bring the problem closer to reality, we do not fix the coherence length and consider a Gaussian distribution function for it. Numerical study of the effects of coherence parameters of Gaussian distribution on far field diffraction pattern is performed.

---
Source: https://tomesphere.com/paper/1906.01330