Challenges ahead as LED lights meet ADAS

Two important trends are transforming the look and feel of today's cars. From the cockpit, Advanced Driver Assistance Systems (ADAS) ranging from simple parking sensors to autonomous braking help drivers handle the increasingly complex challenges of staying safe and legal.

On the outside, LED exterior lighting is inspiring new styles designed to enhance sales appeal and reinforce brand identity. The attractions of LED lighting are not limited to the car body however. LEDs are increasingly used in road signage, everywhere from traffic lights at intersections to road-side signs, motorway notifications, and emergency signals.

LED signage and lighting
LED technology has permeated the automotive space by delivering advantages for car makers, and also for highways authorities who are under pressure to control energy and maintenance costs.

The power consumption of an LED-based traffic-intersection signal is much less than that of a conventional fixture containing incandescent bulbs. Authorities that have converted to LED signals at intersections have reported electrical cost savings in the region of 60-70%.

According to at least one well-known LED traffic signal manufacturer, the latest lamps are as much as 90% more efficient than incandescent bulbs and 15% more efficient than the previous generation of LED lamps. In addition, the lifetime of the LED lamp can be as long as 10 years, whereas an incandescent bulb is expected to last for one year.

This significantly reduces signal maintenance and alleviates traffic disruptions. For a large town, the combined potential savings in utility and maintenance costs can run into millions of dollars over the life of the lamps.

LED exterior lighting for cars began with rear lamps and turn signals, and progressed towards daytime running lamps at the front of the vehicle as the performance and brightness of white LEDs improved sufficiently.

Superior reliability is a major advantage of LED lamps, as far as the automotive industry is concerned. Lamp units can be designed to last the lifetime of the vehicle, which helps to reduce design and production costs.

In addition, the compact dimensions of surface-mount LED emitters has given car stylists more freedom to adapt the size and shape of the lamps to create imaginative designs that meet all the applicable legal requirements.

Another advantage of LED-based lighting is that of easier electronic control, via semiconductors that are more reliable than conventional relays and can support multiple different operating modes such as context-dependent flashing and sequencing.

The outlook for LED lighting in cars and road signage is extremely positive.

Adoption of the technology is likely to continue, permeating an increasing number of signage applications and a wider variety of vehicle models.

ADAS, also, has been enthusiastically adopted both by car makers and end users. ADAS can provide a vital tool to help drivers respond correctly to the large quantities of information typically presented to them during any given journey, as well as helping to deal with traffic conditions and improve comfort and safety.

For car manufacturers, innovative ADAS features can provide a highly visible means of making a vehicle stand out against its competition, as so many aspects of today's cars become standardised according to legal requirements. Manufacturers can also use ADAS to differentiate models within their own ranges.

Vision-based driver assistance
A variety of systems come under the heading of ADAS, including vision-based systems such as rearward parking assistance, blind-spot detection, virtual mirrors, autonomous emergency braking, and traffic-sign recognition.

The number of vision "nodes" per car is expected to rise from the current level of one or two cameras to well into double digits.

The annual global automotive vision systems market is expected to exceed 140 million camera module shipments in 2020, according to Research and Markets' Global and China Vision ADAS Industry Report, 2015-2020. The market for traffic-sign recognition systems in the US alone is predicted to rise from $175 million in 2015 to almost $380 million in 2020.