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ID seeks to reliably distinguish complex specified information from noise. Now Princeton Jason Fleischer and co-author Dmitry Dylov have discovered that there is residual information in “noise” that can be recovered using non-linear optical techniques by “stochastic resonance” with energy from added noise. See:
“Normally, noise is considered a bad thing,” said Jason Fleischer, an assistant professor of electrical engineering at Princeton. “But sometimes noise and signal can interact, and the energy from the noise can be used to amplify the signal. For weak signals, such as distant or dark images, actually adding noise can improve their quality.” . . . The findings were reported online March 14 in Nature Photonics.
“The crucial portion of the experiment came when Fleischer and Dylov placed another object in the path of the laser beam. Just in front of the receiver, they mounted a crystal of strontium barium niobate (SBN), a material that belongs to a class of substances known as “nonlinear” for their ability to alter the behavior of light in strange ways. In this case, the nonlinear crystal mixed different parts of the picture, allowing signal and noise to interact.
By adjusting an electrical voltage across the piece of SBN, the researchers were able to tune in a clear image on the monitor. . . .The contrast makes the person stand out.”
The technique, known as “stochastic resonance,” only works for the right amount of noise, as too much can overwhelm the signal. It has been observed in a variety of fields, ranging from neuroscience to energy harvesting, but never has been used this way for imaging.”
See full news article: Turning noise into vision
Nature Photonics Published online: 14 March 2010 | doi:10.1038/nphoton.2010.31
Dmitry V. Dylov & Jason W. Fleischer
Nonlinear self-filtering of noisy images via dynamical stochastic resonance
Abstract
From night vision and objects overwhelmed by sunlight to jammed signals and those that are purposely encrypted, detecting low-level or hidden signals is a fundamental problem in imaging. Here, we develop and exploit a new type of stochastic resonance, in which nonlinear coupling allows signals to grow at the expense of noise, to recover noise-hidden images propagating in a self-focusing medium. The growth rate is derived analytically by treating the signal–noise interaction as a photonic beam–plasma instability and matches experimentally measured resonances in coupling strength, noise statistics and modal content of the signal. This is the first observation of nonlinear intensity exchange between coherent and spatially incoherent light and the first demonstration of spatial coherence resonance for a dynamically evolving signal. The results suggest a general method of reconstructing images through seeded instability and confirm information limits predicted, but not yet observed, in nonlinear communications systems.
See also: United States Application US20100020204
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Now wonder if such methods can be used to remove the “noise” of evolution? Can “non-linear glasses” be used to improve insight?
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April 6, edited per discussion with pelagius at 2 below.