Instantaneous speckle reduction? Yes, but there is no free lunch!
Häusler G, Dötzer F, Mantel K (2018)
Publication Type: Conference contribution
Publication year: 2018
Publisher: SPIE
Book Volume: 10834
Conference Proceedings Title: Proceedings of SPIE - The International Society for Optical Engineering
Event location: Janow Podlaski
ISBN: 9781510622975
DOI: 10.1117/12.2317925
Abstract
We are motivated by the question if scanning laser projection with low speckle noise is possible. Scanning laser projection requires "instantaneous" speckle reduction, within a few nanoseconds-meaning that no moving diffusors can be used. We will argue that instantaneous speckle reduction is possible by conversion of spatial coherence to spatial incoherence-but nature demands for a compensation. The cost can be estimated via the information theoretical concept "channel capacity", which incorporates the etendue as well as the signal-to-noise ratio. We will show that an optical system with low spatial coherence (=low speckle noise) must provide significantly more degrees of freedom than a coherent imaging system. The consequence for the technical optical system is serious: Significant speckle reduction can only be achieved by an excessively large projection aperture. This is not just a sophistic consideration, it seriously restricts the design of scanning laser projectors.
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Germany (DE)How to cite
APA:
Häusler, G., Dötzer, F., & Mantel, K. (2018). Instantaneous speckle reduction? Yes, but there is no free lunch! In Leszek R. Jaroszewicz, Malgorzata Kujawinska (Eds.), Proceedings of SPIE - The International Society for Optical Engineering. Janow Podlaski, PL: SPIE.
MLA:
Häusler, Gerd, Florian Dötzer, and Klaus Mantel. "Instantaneous speckle reduction? Yes, but there is no free lunch!" Proceedings of the 7th International Conference on Speckle Metrology, Speckle 2018, Janow Podlaski Ed. Leszek R. Jaroszewicz, Malgorzata Kujawinska, SPIE, 2018.
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