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Light emitting diode (LED) modules (standardized light sources) for use in automotive illumination design will soon become available in production volumes. Designing products with these devices is not the same as working with conventional tungsten halogen or high intensity discharge (HID or Xenon) light sources. There are a number of LED module characteristics which must be kept in mind when designing lighting systems.

Light Emitting Diodes (LEDs) are commonly used for signaling and marking functions on commercial vehicles. Recent work on new LED modules will allow the use of LEDs for illumination functions.

This document explains the rationale for a number of confusing provisions found in lighting Regulations and Standards.

Headlights with Light Emitting Diodes (LEDs) as the light source have come on the market but are complex and expensive. Recent work on new LED modules for headlights will allow a single LED module for each function, making LED headlights practical for mass market vehicles.

This report consists of an investigation of human perceptions of narrow band width coloured light sources (Light Emitting Diode or LED) and wide band width coloured light sources (filtered incandescent). Any difference in perception of these light sources has many implications for design of lighting devices. Testing was performed to evaluate the differences, if any.

It is well known that if there is too much light intensity too close to the vehicle, the driver's eye adapts to the high intensity. The driver's ability to see obstacles far away is then decreased. This is why headlamp intensities are limited at 4D. The 1.5D, 2R headlamp test point with no maximum values specified may or may not be located low enough in the pattern to cause this phenomenon with current passenger car headlamp mounting heights. Discussions with engineers who have been involved in headlamp optical design for many decades (Reference 1) indicates that the original function of the 1.5D, 2R test point was to find the maximum candela (cd) contained within the beam. Searching for the maximum cd with a hand crank goniometer was a difficult and lengthy job. With the filament sizes and focal lengths used in headlamps in the US in past years, the maximum was always found in close proximity to this point. I, too, observed this in the early years of my career.

A lower beam light distribution which is optimized for pedestrian detection has been devised. This paper examines the effects of the change to opposing driver glare.