New cost-effective sensor for the characterization of automotive headlamps by measurements in the near field
| Autor: | Santiago Royo, Maria Jesus Arranz, Michel Cattoen, Josep Arasa, Thierry Bosch |
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| Přispěvatelé: | Universitat Politècnica de Catalunya. Departament d'Òptica i Optometria, Universitat Politècnica de Catalunya. GREO - Grup de Recerca en Enginyeria Òptica |
| Jazyk: | angličtina |
| Rok vydání: | 2006 |
| Předmět: |
Ciències de la visió::Òptica física [Àrees temàtiques de la UPC]
Computer science Headlamp Fotometria Automotive industry Automobile industry and trade Automotive Near and far field Imatges -- Processament Luminance Photometry (optics) Photometry Optics Image processing Calibration Astrophysics::Solar and Stellar Astrophysics Light beam Light sources Electrical and Electronic Engineering Instrumentation Remote sensing CCD business.industry Metals and Alloys Astrophysics::Instrumentation and Methods for Astrophysics Condensed Matter Physics Surfaces Coatings and Films Electronic Optical and Magnetic Materials Near-field Measuring principle Optical testing Headlamps business Automòbils -- Indústria i comerç |
| Zdroj: | UPCommons. Portal del coneixement obert de la UPC Universitat Politècnica de Catalunya (UPC) |
| Popis: | Nowadays, European Normative regarding headlamp validation evaluates the photometric distribution of the source as a series of illumination values measured at a plane placed 25 m away from the light source. An innovative and inexpensive approach to test this photometric distribution is presented. We propose to sample the luminance field at a plane placed a few centimetres in front of the headlamp displacing a CCD camera at an adjustable number of positions. A specific processing of the sequence images allows simultaneously measuring the direction of propagation through deflectometric techniques and the energy of the light beams leaving the source through photometric techniques. Image-processing techniques may then be applied to these data in order to evaluate the photometric distribution in any predefined distant surface. An overview of the unit, of the measurement principle, and of the main calibrations performed is presented along the paper. In particular, the techniques for the calibration of the global constant converting CCD grey level values into photometric units are described and applied to different distributions. Finally, the comparison of computed illumination maps using the unit with reference measurements at photometric tunnels is presented, showing good agreement and demonstrating the validity of the approach. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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