Temporal coherence properties of laser modules used in headlamps determined by a Michelson interferometer
-
Valerie Popp
,
Burkhard Fleck
Abstract
In this work, an investigation of the temporal coherence properties of radiation which is emitted by laser modules integrated in headlamps is presented. The motivation for these measurements was difficulties concerning the field of classification for laser products which function as conventional headlamps. Based on an experimental setup including a Michelson interferometer, a goniophotometer and a spectrometer, coherence lengths of 92.5 and 147.0 μm are obtained for two different laser modules. The results show that the temporal coherence of the examined radiation is appreciably higher than the temporal coherence of conventionally produced white light. Therefore, at this point in time, laser modules used in headlamps cannot be considered as customary white light sources.
About the authors
Valerie Popp studied Ophthalmic Optics/Optometry and Laser- and Optotechnologies at the University of Applied Sciences of Jena, Germany. During a student internship in the Development Innovations Light/Visibility department at Audi in Ingolstadt, Germany, she investigated the temporal coherence properties of laser modules used in headlamps. She wrote her master’s thesis in the field of refractive laser surgery at Technolas Perfect Vision in Munich, Germany. At the moment, she is on parental leave.
Philipp Ansorg studied Physics at the University of Göttingen, Germany. Afterwards he worked on his PhD at Audi and the Light Technology Institute at the Karlsruhe Institute of Technology, Germany. His research focuses on laser based headlamp systems. Since 2018 he works in the Light functions development department at Audi in Ingolstadt, Germany.
Burkhard Fleck studied Physics at the University of Jena. After completing his PhD, he worked in the field of coherent optical measurement technology. He habilitated in 2000 at the Faculty of Physics and Astronomy at the University of Jena. In 2001 he became professor for Technical Optics and Physics at the Ernst Abbe University (University of Applied Sciences) in Jena.
Cornelius Neumann studied Physics and Philosophy at the University of Bielefeld, Germany. After his PhD, he worked for the automotive supplier Hella in the advanced development for Automotive Lighting. During his time at Hella he was responsible for signal lighting, LED application and acted as a director of the L-LAB, a laboratory for lighting and mechatronics in public private partnership with the University of Paderborn, Germany. In 2009, he became Professor for Optical Technologies in Automotive and General Lighting and one of the two directors of the Light Technology Institute at the Karlsruhe Institute of Technology, Germany.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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© 2020 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Community
- News
- Topical Issue: Automotive Lighting; Guest Editor: Cornelius Neumann
- Editorial
- Automotive lighting
- Letter
- Development of HD-headlamps with high-performance projectors
- Research Articles
- Imaging vehicle-to-vehicle communication using visible light
- Manufacturing of volume holographic cell arrays for usage with uncollimated LEDs in automotive applications
- Personalised neural networks for a driver intention prediction: communication as enabler for automated driving
- Development of a high resolution scanning RGB laser headlamp
- Review articles
- Temporal coherence properties of laser modules used in headlamps determined by a Michelson interferometer
- Influence of the perceived size of a light source on non-visual effects in humans
Articles in the same Issue
- Frontmatter
- Community
- News
- Topical Issue: Automotive Lighting; Guest Editor: Cornelius Neumann
- Editorial
- Automotive lighting
- Letter
- Development of HD-headlamps with high-performance projectors
- Research Articles
- Imaging vehicle-to-vehicle communication using visible light
- Manufacturing of volume holographic cell arrays for usage with uncollimated LEDs in automotive applications
- Personalised neural networks for a driver intention prediction: communication as enabler for automated driving
- Development of a high resolution scanning RGB laser headlamp
- Review articles
- Temporal coherence properties of laser modules used in headlamps determined by a Michelson interferometer
- Influence of the perceived size of a light source on non-visual effects in humans
