Remote HID Headlamp Systems

Solid State Lighting II

McColgan

2002

Considerations for the use of white light emitting diode (LED) sources to produce illumination for automotive forward lighting is presented. Due to their reliability, small size, lower power consumption, and lower heat generation LEDs are a natural source choice for automotive lighting systems. Currently, LEDs are being successfully employed in most vehicle signal lighting applications. In these applications the light levels, distributions, and colors needed are achievable by present LED technologies. However, for vehicle white light illumination applications LEDs are now only being considered for low light level applications, such as back-up lamps. This is due to the relatively low lumen output that has been available up to now in white LEDs.With the advent ofnew higher lumen packages, and with the promise of even higher light output in the near future, the use of white LEDs sources for all vehicle forward lighting applications is beginning to be considered. Through computer modeling and photometric evaluation this paper examines the possibilities of using currently available white LED technology for vehicle headlamps. It is apparent that optimal LED sources for vehicle forward lighting applications will be constructed with hereto undeveloped technology and packaging configurations. However, the intent here in exploring currently available products is to begin the discussion on the design possibilities and significant issues surrounding LEDs in order to aid in the design and development of future LED sources and systems. Considerations such as total light output, physical size, optical control, power consumption, color appearance, and the effects of white LED spectra on glare and peripheral vision are explored. Finally, conclusions of the feasibility of current LED technology being used in these applications and recommendations of technology advancements that may need to occur are made.

Section: Total Light Outputmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

White LED sources for vehicle forward lighting

Solid State Lighting II

McColgan

2002

“…Similar systems, typically of larger scale, are beginning to be used for general interior and exterior automotive lighting systems, including tail, puddle, and forward lighting applications. [1][2] [3] Since image formation is not the goal in these applications, the refraction and total internal reflection (TIR) properties of light pipes can be efficiently used to collect, transport, and output light. [4] Light pipes can also be used to tailor the output light distribution to the needs of the illumation task.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Fabrication Errors on the Performance of Injection Molded Light Pipes (Waveguides)

SAE Technical Paper Series

2001

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Analytical model of flux propagation in light-pipe systems

Hough

2004

Opt. Eng

An analytical model of light propagation in rectangular light pipes, termed the flux confinement diagram (FCD), is developed. Based on the edge ray concept of nonimaging optics, the FCD is a construction that describes the angular distribution of flux propagating in a light pipe depending on a light pipe's index of refraction and its geometry. With the FCD model, the angular ''mode'' of a ray can be defined at any plane in the system. The FCD model is developed here and used to describe flux input coupling, transport, and output coupling in light-pipe illumination systems. The practical example of a flux loss prediction due to a geometrical change (a bend) is examined using the FCD and compared to a ray-tracing analysis. We discuss how this model of flux propagation is a useful tool to aid in ''first-order'' design and layout of light-pipe illumination systems.