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 PL

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.

Authors with CRIS profile

Gerd Häusler Naturwissenschaftliche Fakultät Florian Dötzer Lehrstuhl für Experimentalphysik (Optik)

Involved external institutions

Max-Planck-Institut für die Physik des Lichts (MPL) / Max Planck Institute for the Science of Light DE 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.

BibTeX: Download