The Future Of Automotive Lighting: Lasers Or LEDs?
By John Oncea, Editor
The future of automotive lighting is likely to involve both laser and LED technologies, with each offering distinct advantages for different applications. While LED technology is currently more widespread and offers numerous benefits, laser lighting shows great potential for specific applications, particularly in high-intensity headlamps.
Lasers and light-emitting diodes (LEDs) have existed for decades, each having evolved significantly since their arrival in the 1960s. Both have improved in efficiency, power output, and wavelength range while finding use in numerous applications across various fields.
For instance, lasers are used for optical storage, telecommunications, medicine, manufacturing, scientific research, defense, and consumer electronics. LEDs are used for lighting, displays, indicators on electronic devices, communications, horticulture, and UV disinfection.
Both have found use in the automotive industry, something we’ll cover later. But first, a quick look at these two lighting technologies.
Differences Between Lasers And LEDs
Lasers and LEDS have different properties that make them better suited for the different applications noted above. Lasers are more powerful and operate faster than LEDs, and they can transmit light farther with fewer errors. They also have more specific characteristics, such as size, shape, intensity, and wavelength, which can make them better for some applications.
For example, in bio-instrumentation applications, lasers can offer superior performance and lower overall cost per photon. In medical applications, low-level laser therapy can deliver more energy into tissue than LEDs, making it more effective for treating deeper tissue. However, lasers are more expensive than LEDs.
LEDs are the standard light source and are less expensive than lasers. They also have larger emitting regions and longer lifetimes. LEDs can be effective in some medical applications, such as treating inflammatory conditions, joint or muscle pain, and during pregnancy. For example, a dermatologist might prescribe an LED session after laser treatment to reduce inflammation and redness.
Other differences between lasers and LEDs are:
- Light Emission: Lasers emit light through stimulated emission. This results in a highly focused, coherent beam of light. LEDs, on the other hand, produce light through a process called spontaneous emission. When an electric current passes through the semiconductor material of an LED, electrons combine with holes and release energy in the form of light.
- Directionality: Lasers emit a straight beam that travels in a straight line. Unlike LEDs, lasers don’t scatter their light. LED light is dispersed and multidirectional. This means that LED rays spread as they travel farther from the light source.
- Applications: Lasers are specialized for specific tasks due to their focused beam. They find applications in medical surgeries, metal cutting, optical communication, and more. LEDs are commonly used for illumination in various applications. You’ll find them in indoor and outdoor lighting, TVs, smartphones, computers, and automotive lighting.
- Wavelength: Lasers produce a single-band wavelength, resulting in a monochromatic beam. LED rays cover a broad band of wavelengths, resulting in various colors (such as red, green, and blue).
- Speed: Laser beams travel at the speed of light in a straight line. LED rays travel slower than laser rays due to their dispersed nature.
- Output Power: Lasers have higher output powers compared to LEDs. LEDs operate at lower drive currents and are generally less powerful.
Long story short: if you see a focused, intense beam of light, it’s likely a laser. If the light is dispersed and coming from various directions, it’s probably an LED.
Lasers, LEDs, And Automotive Lighting
Lasers and LEDs are both being utilized in innovative ways for automotive lighting, each offering unique advantages. Let’s start with lasers and their use in high-intensity headlamps which can produce a high beam with a luminous intensity of around 100,000 candelas, significantly brighter than LED alternatives. Laser headlights also can be extremely compact, with some prototypes measuring only 30 mm in diameter.
Laser headlights can produce a much narrower light beam for long distances, improving visibility by producing light up to a thousand times brighter than an LED with less energy consumption.
Advanced safety features, such as improving visibility in treacherous conditions such as severe snow, rain, and especially fog, are another benefit provided by laser headlights. So too is their ability to minimize glare while being vision safe.
LEDs, on the other hand, are being used by Toyota, Lexus, Audi, BMW, Nissan, and Mercedes for various lighting functions, including headlights, taillights, and interior lighting. Part of the reason is their energy efficiency: LED lights consume less power than traditional options, reducing the load on a vehicle's electrical system.
LED lights also have a much longer lifespan compared to halogen bulbs and can be adjusted for different brightness levels to create dynamic lighting effects. They are also brighter than halogen lights, providing better road illumination, especially in poorly lit areas.
Of course, the two don’t exist apart from each other and some manufacturers are exploring hybrid applications. For example, BMW has developed headlights comprising a laser high beam and LED dipped beam. Both technologies are also being used to create high-resolution displays for dashboards, instrument clusters, and head-up displays, as well as for the development of adaptive lighting systems that can adjust to real-time road conditions.
Both laser and LED technologies are playing crucial roles in advancing automotive lighting, with LEDs currently being more widespread and lasers offering promising developments for specific high-performance applications. This fact is driven home by a MarketsandMarkets report that found the automotive lighting market, valued at $22.5 billion in 2023, is expected to reach $30.4 billion by 2030. “The market for automotive lighting has been pushed by government’s adoption of sophisticated safety measures and the rise in demand for luxury vehicles,” writes MarketsandMarkets.
Times Tech agrees that, while the future of automotive lighting will depend on continued innovation and integration of both technologies to enhance safety, efficiency, and design possibilities, government regulations will play an oversized role.
“Government regulations in Europe and North America are driving the Automotive Lighting Market growth,” writes Times Tech. “Strict lighting standards aim to enhance safety and visibility, crucial for reducing road accidents. Innovations such as LED and adaptive lighting systems, supported by significant R&D investments, are meeting these regulatory demands.”
What The Future Holds For Automotive Lighting
The future of automotive lighting will see a transition from fixed hardware to software-defined systems, according to the Automotive Skills Development Council (ASDC). “Digital micromirrors will grant real-time beam shaping for maximum visibility. Embedded laser arrays in lights and body panels will enable vehicle communication for early hazard warnings and signaling intent.
“Autonomous vehicles will leverage high-precision lighting for navigation. Interactive exterior and ambient interior lighting will facilitate communication with people sharing the road and create personalized spaces. Intelligent, adaptive lighting innovations will fundamentally transform how vehicles illuminate and interact with their surroundings.”
ASDC also anticipates higher efficiency, lower costs, and smaller LED packages and that, “Matrix LED headlights with over 1,000 controllable segments will become more common, enabling highly adaptive beams.” Look for lasers to evolve from limited high-beam applications to more widespread use cases like brake lights, turn signals, and accent lighting with costs dropping as adoption increases.
Other advancements to look forward to include:
- Digital micromirrors: Tiny addressable mirrors will grant digital control over light distribution and beam patterns. The software will be able to reshape beams in real time for maximized visibility.
- Embedded lighting: Light sources will integrate into headlight housings rather than protrude outward. This allows for slimmer, more aerodynamic designs. Lasers embedded into body panels could provide interactive exterior lighting.
- Vehicle communication: Headlights and taillights will talk to each other for early collision warnings and to coordinate beams. Vehicle-to-infrastructure communication also will become possible.
- Augmented reality: Lighting could project guides, alerts, and other information onto the road ahead. Laser-assisted vision may also enhance pedestrian detection capabilities.
- Self-driving adaptation: Fully autonomous vehicles won't need complex lighting. But programmable, interactive lights could communicate vehicle intentions to pedestrians.
- Personalized experiences: Customizable ambient lighting inside vehicles will create immersive, relaxing, or energizing environments. Exteriors could also be personalized.
The field of automotive lighting has advanced significantly, moving from traditional bulbs to cutting-edge technologies such as adaptive LEDs and laser headlights. These new technologies offer improved visibility, extended range, and enhanced safety features.
Looking ahead, the future of automotive lighting will involve software-defined lighting, advanced beam control, vehicle communication, and personalized lighting experiences. However, some challenges need to be addressed, including heat management, precise control, reliability, and cost reduction.
These advancements are reshaping the future of vehicle lighting, making it more intelligent, efficient, and customizable, while also enabling new forms of communication and augmented reality. Importantly, these lighting systems will need to adapt as cars transition from human-driven to fully autonomous.