Summary

Proceedings of the 2012 International Symposium on Nonlinear Theory and its Applications

2012

Session Number:B3L-D

Session:

Number:450

Spatial Light Modulator Feedback System Configured as An Excitable Medium

Aaron M. Hagerstrom,  Thomas E. Murphy,  Rajarshi Roy,  

pp.450-453

Publication Date:

Online ISSN:2188-5079

DOI:10.15248/proc.1.450

PDF download (667.5KB)

Summary:
We construct a dynamical imaging system which includes a micromirror spatial light modulator (SLM) and camera, connected in a feedback loop. This system is configured as a cellular automaton which models an excitable medium. The cells in this automaton correspond to pixels on the SLM screen, and are updated according to the Greenberg-Hastings rules [1, 2]. The cells can be excited, refractory, or quiescent. If a cell is excited, a corresponding area of the camera's detector will be illuminated. Cells will be excited if they are in a quiescent state and the intensity detected by the corresponding camera pixel is above a threshold. After firing, a cell enters a refractory period, and must wait for some number of iterations before it can fire again. Due to optical spillover, which is a characteristic of the imaging system, there is coupling between adjacent cells. This system supports spiral waves, target waves, and incoherent and synchronized firing patterns. We see patterns which display propagating fronts which coexist with global oscillations.

References:

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