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that can improve safety for drivers
at night. This flexibility externally
also transfers to interior lighting
as LEDs are far easier to control
than incandescent lighting. Their
much lower size and weight also
means that implementation of
LEDs are simpler and they can be
mounted with standard fixings such
as clamps or adhesives - in fact in
any way that allows any thermal
build-up to dissipate evenly. LEDs
are also evolving themselves, with
new materials opening up new
applications for vehicles. Galium
Nitride technology, for instance,
now allows LEDs to operate at
greater efficiency and at higher
temperatures.
LEDs have had a profound
effect on lighting in vehicles.
These advantages are both in
the large range of options that
were unavailable using previous
technologies, and in the degree of
flexibility and control that they have
given automotive designers. LEDs
for interior use have presented
designers with a choice of colors,
brightness and intensity than
ever before, while allowing them
to account for changes in the
environment. External lighting
applications have also brought a
huge amount of choice to designers
for high power LEDs in a wide
variety of colors. To give an example
from one manufacturer, OSRAM
Opto Semiconductors manufactures
a wide range of LEDs and LED
modules in precise color options.
According to the manufacturer, the
company’s OSTAR Headlamp Pro,
“The color coordinates of the LEDs
correspond to the white field of ECE/
SAE, in which the red component
of the LED is greater than 5%.…".
Mercedes-Benz boast scientifically
optimal lighting that is designed
to enhance the brand, while giving
the best possible experience to the
driver. Lower-end manufacturers
are also starting to implement
some of the lessons learned from
premium manufacturers.
LED ambient lighting today has
evolved from what was once purely
cosmetic to improve the look and
feel of a car’s interior and make the
car “feel” that it is better quality, to
an integral part of the car’s safety
features. The ambient lighting can
be set up to assist the driver when
entering or leaving the car, easily
see and activate the controls of
the vehicle, while also helping the
driver feel more relaxed.
Of course, that is not to suggest that
ambient lighting is merely cosmetic,
it must be functional as well. For a
designer, there are other aspects
to consider in the design, such as
the optimal number of lights and
what the lighting will look like, both
internally and externally. How can
the lighting keep the driver alert,
without feeling strained? Can he/
she locate and apply the controls
easily?
Applications
LEDs are the main luminaire used
in vehicular lighting design because
of their long lifespan, low-power
use, flexibility and huge range of
coloring options. These lights can
be found in the roof light, behind
instrument and display panels,
in the controls and switches, and
even designed into door panels to
provide the lighting for the driver to
enter or leave the vehicle.
There have since been many studies
on every aspect of ambient lighting
on emotions and perceptions in both
vehicles and buildings, but the one
mentioned earlier by BMW in 2009
remains the most comprehensive to
date. This research has provided the
most data for manufacturers on the
psychology of automotive ambient
lighting. Many other automotive
manufacturers also use LED ambient
lighting to make their own offerings
stand out. Taking the lead for user
customization is Mercedes Benz.
The company’s high-end vehicles
can offer customers a choice of
seven different colors, five dimming
levels and four dimming zones.
LEDs have revolutionized almost
every area of car lighting, most
predominantly, so far, in headlights.
As well as giving the inherent
advantages we expect from solid
state lighting, such as longer
service life, higher efficiency and
higher reliability, LED headlights
provide a range of new features
Automotive
Special Edition
Figure 2: The OSRAM OSTAR
Headlamp Pro LED has
scalable brightness, adapts
to ambient conditions, and
mounts many ways, including
soldering to a flexible printed
circuit board as shown
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