More efficient than LED or Xenon headlamps, and using far less energy – the German manufacturer BMW claims laser light is the next logical development in car light development.
Laser light consumes over 50% less energy than LEDs, whilst generating more light per watt. Currently, laser headlights do not comply with US regulations, but it’s expected that Europe may be the first to approve them.
Lasers have the potential to be more powerful, more efficient, and smaller than other headlamp types – all at the same time.
Additionally, BMW lighting functions such as Adaptive Headlights, the “Dynamic Light Spot” spotlighting system and the “Anti-Dazzle High-Beam Assist” will be easy to implement using laser light. According to BMW, it will also be possible to use laser lighting to implement completely new functions, which will have only minimal power consumption.
An advantage of laser technology, and one which the BMW engineers intend to use to full effect, is its high efficiency.
Ordinary light, like sunlight, is made up of many different wavelengths, or colours, of light.
The light from a laser contains exactly one colour or wavelength rather than a lot of different wavelengths. Scientists say that laser light is ‘monochromatic’, meaning ‘of one colour’.
All the wavelengths are in phase. That is, they are all ‘waving’ together, like a well-timed audience ‘wave’ at a football game. All the wave crests (high points) and troughs (low points) are lined up.
While light waves from ordinary sources (such as torches, lightbulbs, or the sun) spread out in all directions, laser light waves all travel in the same direction, exactly parallel to one another. This means that laser light beams are very narrow and can be concentrated on one tiny spot.
Lasers are concentrated light of one frequency, which is focused in a tight beam. This can cause serious eye damage in seconds, as it is extremely powerful and highly targeted. According to BMW, “…the complete eye safety for all road users and the complete reliability of laser technology in day-to-day use has top priority.”
BMW’s experts assure us that “before the light from the tiny laser diodes is emitted on to the road, the originally bluish laser light beam is converted by means of a fluorescent phosphor material inside the headlight into a pure white light which is very bright and ‘pleasant to the eye’.”