Study of active millimeter-wave image speckle reduction by Hadamard phase pattern illumination
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Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization
Published on: July 5, 2016
Gaetan Koers1, Ilja Ocket, Qi Feng
1Lab for Microelectronics and Photonelectronics, Electronics and Information Processing Department, Vrije Universiteit Brussel, Brussels, Belgium. gkoers@etro.vub.ac.be
Abstract:
Active millimeter-wave images typically exhibit characteristic speckle noise, due to the coherence of artificial millimeter-wave sources. We study the Hadamard speckle contrast reduction (SCR) technique, which has been successfully used in laser projection systems, in the context of millimeter-wave imaging. We show the impact of Hadamard pattern order and size and of image and pattern resolution on speckle reduction efficiency. Practical limitations of Hadamard pattern implementations and their effect on speckle reduction efficiency are also discussed.
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