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Updated: Feb 2, 2026

How to Build a Laser Speckle Contrast Imaging LSCI System to Monitor Blood Flow
Published on: November 11, 2010
Experimental demonstration of a flexible DOE loop with wideband speckle suppression for laser pico-projectors
Abstract:
The compact and straightforward construction of a pico-projector using an original method for speckle suppression via a simple 1D diffractive optical element (DOE) structure on a loop of flexible film with tracked motion is demonstrated. The 1D-DOE structure is based on binary pseudorandom sequences. The method requires very little energy and space and can decrease speckle noise to levels below the detection sensitivity of the human eye. Large speckle suppression coefficients and low speckle contrasts are obtained for blue, green, and red lasers. Speckle suppression efficiency will be further significantly improved by optimization of the DOE structure and film material.
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