Definition of the cut-off of vehicle headlights

CIE 183:2008
Division 4
978 3 901906 64 0

A precise objective definition of low-beam visual cut-off is necessary, since a requirement for correct aiming of these beams is specified within all the existing regulations.

At present, aiming of low-beam headlamps is performed visually in Europe and USA (since 1997), using the cut-off line in the beam pattern. A good definition of a visual cut-off is required to allow uniformity in interpretations.

This report provides a survey of studies into low beam visual cut-off that have been carried out in Europe and North America. Based on these studies, a recommendation is made for the definition and measurement of the cut-off line of a low-beam headlamp by photometric means.

The publication is written in English, with a short summary in French and German. It consists of 19 pages with 6 figures.

The following members and advisors of TC 4-10 "Automobile Lighting Systems" took part in the preparation of this Technical Report:


  • J.L. Banks, Great Britain
  • J. Bergin, USA
  • M.A.R. Bernhard, Switzerland
  • J.Th. Bindels, The Netherlands
  • L. de Brabander, Belgium
  • M. Cejnek, Czech Republic
  • G. Dorleans, France
  • G.R. Draper, Great Britain
  • A.J. Fisher, Australia
  • G. Furlan, Italy
  • K. Honda, Japan
  • H.G. Hornig, Germany
  • H. Löfgren, Sweden
  • D. Moore, USA
  • W. Pollack, Germany
  • R. Rendu, France
  • W.H.J. Sator, South Africa
  • Chr. Schmidt, Germany
  • H.J. Schmidt-Clausen, Germany
  • N. Stepanov, Russian Federation
  • G. Székács, Hungary
  • F. Takata, Japan
  • H. Westermann, Germany
  • Tai-Ming Zhou, China


  • Th. Althoff, Germany
  • Rong An Liu, China
  • V.D. Bhise, USA
  • S. Holló, Hungary
  • S. Ottó, Hungary
  • B. Tansley, Canada
  • J.G. White, Canada
  • K. Yokoi, Japan

The final draft was prepared by:

  • K. Manz, Germany
  • A.C.M. de Visser, The Netherlands (chair from 2003)