And, when the subject is lasers, you cannot help but get excited. Immediately one thinks of that iconic exchange between James Bond and Goldfinger, ‘Do you expect me to talk?’ ‘No, Mr Bond. I expect you to die.’ But the reality of this laser technology is that it won’t kill you, in fact, quite the opposite, one day it could save your life.
In September 2008 the European Union Directive 2008/89/EC required all passenger cars and small vans built after February 2011, to be fitted with daytime running lights (DRL). This was a sign of the importance the industry was placing on lighting when it came to reducing the number of deaths in road accidents. While ratios have been reduced in the daytime, there is still a problem between the hours of dusk and dawn. This is where the new innovation of laser headlight technology could change, quite literally, the face of the automotive industry forever.
Halogen bulbs in cars were gradually replaced by LED technology by the end of 2008 but since then the industry has been looking for more innovation. Luckily, illumination wasn’t far away, with engineers developing a more efficient, lightweight, and adaptive headlight technology. It came in the form of laser headlights, the result of a global collaborative development within consumer electronics giant Sharp, which included Sharp’s European Research arm based in Oxford.
Jon Heffernan, Director at Sharp Labs, explains that it was a natural progression for Sharp, having mass-manufactured the laser for the CD and DVD in the eighties, as well as the development of LED technology over the last 40 years. Humans Invent profiled the Molecular Beam Epitaxy (MBE) machine that was used in the development of the lasers for DVD and Blu-Ray.
“Sharp has a long history of laser and LED manufacturing, and it was actually the first company to mass-produce lasers for the production of CDs back in 1982. We have seen LED lighting replace halogen and incandescent lighting in the automotive industry, in back-lighting for LCD TVs, and we are now seeing it emerge in household lighting. With this expertise to hand, we asked the simple question, could we apply laser technology to this revolution in lighting? The answer was yes.”
The innovative result is a laser headlight that is not only more efficient and lighter but brighter. “The advantage of a laser is that we can focus a lot of light into a small area and this light can be much more directed than a HID or LED,” Heffernan explains. “We use an array of 405nm lasers (those used in Blu-ray players), focussed on to a phosphor material that converts blue light to white. So this allows us to create a small, compact and very bright light source.
“The headlight consists of the light source and a lot of optics such as mirrors. So with a more compact laser source there is a lot more design freedom for the overall headlight optics”
Essentially, the light waves in the laser are a constant length, and have a constant phase difference. This result is a near parallel beam, with an intensity a 1000 times brighter than an LED source. This gives more flexibility in designing the headlights giving for example better visibility for the driver.
The belief is the technology will improve safety in cars for two reasons. Firstly, the brighter light source, and secondly, the potential to incorporate future sensory technologies.
“The light originates from a very small area and we can separate the main laser from the phosphor, which creates the white light,” Heffernan explains. “We then have the potential to make smaller and less bulky headlights at the front of the car reducing the impact of any kind of collision, especially on the safety of pedestrians.
“The second point is the adaptive element of the technology. Because you are able to make a smaller, more efficient system, you have the ability to control the light far more”, Heffernan says. “the source is more intense and directed so you can design the optic to feature better control methods – for example changing the direction of the beam. This gives the potential for easier application of adaptive front lighting”
The lightweight laser tech will be easier on impact during a crash, while also giving pedestrians a better chance of seeing an oncoming vehicle. Furthermore, in the future the headlights will be easily adaptable with sensors and remote reaction controls – smart tech.
“We are seeing a lot more smart technology in the automotive industry, particularly reactive technology,” Heffernan explains. “For example in the future, the car can sense and react to other cars on the road, and importantly any number of hazards that are on the road depending on road conditions.”
Heffernan believes in the not too distant future your car will automatically react to its surroundings – making clever decisions to aid the driver.
“A simple adaptive function would be high and low beam headlights. At the moment drivers have low beam and high beam functions, but there is a future push to have it automated. Sensors will pick-up what is on the road and who is on the road, reacting accordingly. You won’t just have high or low beam, you will have a gradient from high to low, and also some directional beaming appropriate to road conditions”.
“The advantages of the laser tech, is a system that doesn’t have any moving parts. Without lasers, you would have to put in mechanical parts, which effects the size and weight of the headlight. The laser advantage is we can change the profile by controlling the light beam itself because of the focusing properties of the laser. So this is a massive advantage in bringing infuture adaptive and responsive headlight technology.”
On a broader level, the development of the lasers means any area that is tricky to light could be installed with laser technology, because you can separate the light source and the laser using fibre optics.
“If we look at the unique advantages of laser lighting, such as the design flexibility, size, and weight, you move more to the idea of remote lighting,” Heffernan explains. “So, the source of the light can be separated from where the actual light comes out. An example of this would be delivery of the lights through an optical fibre.
“So, you would have the laser beam in one part, and you can then deliver the light source through the fibre, and the light actually comes out somewhere else. The light source can be located anywhere, and we are looking at areas in general lighting where you could have difficulty installing lighting – a tricky architectural design, or even an extreme build on the side of a mountain.”
So the future looks good for incorporating laser lighting across all parts of our life, at home and in the car. One area where we may see this technology sooner rather than later is in the electric car market.
“There is no doubt that the size, weight and efficiency could be of real help in the development of electric vehicles in the future,” Heffernan reveals. “There is quite a big growth in this market currently, and this would be a key future technology that could help with the development of the mass-produced electric car.”
There is no official time-scale on when we could see laser technology on the roads, but Heffernan did tell Humans Invent, “Sharp recently presented this work at an international automotive conference and received a lot of interest, so we will have to wait and see what the immediate future holds.” This is promising, and despite the unknown launch date, the fact that laser lighting could impact all forms of lighting in the future is an exciting thought.