Innovative applications for LEDs in automobiles

New applications for LED lighting in cars include a dome light with a removable flashlight, a wing mirror with an LED warning light, and an infrared driver monitoring system.

Aug 31st, 2006
Content Dam Leds En Articles 2006 08 Innovative Applications For Leds In Automobiles Leftcolumn Article Thumbnailimage File
CML builds LED flashlight into vehicle dome light

CML Innovative Technologies has developed an innovative interior light for automobiles that also incorporates a removable LED flashlight.

Dodge Caliber
The Dodge Caliber is the first car to incorporate the new interior light, which includes both a traditional dome light and a separate, removable flashlight. The cargo lamp uses an incandescent bulb.

CML dome light
The flashlight contains white LEDs, and can be operated at 100% or 50% brightness. Its rechargeable batteries provide one hour of autonomous operation once the flashlight is removed from the dome light.

CML's Fabien Noir says that the flashlight uses two standard through-hole 5mm-diameter LEDs, driven at 20-30 mA. "High power LEDs were not suitable due to cost and technical standpoint issue such as heat dissipation and integration with electronics," he says.

CML believes the flashlight will prove popular as it can be used in a variety of situations either inside or outside the car, for example to look for objects under the seat or in a handbag, to change a wheel, or to signal in case of emergency.

Audi wing mirror warning

Many cars have wing mirrors with built-in turn signal indicators, or with puddle lights to illuminate the ground as the driver exits.

Audi Q7 wing mirror system
The wing mirrors of the new Audi Q7 have a unique feature; an LED signal that warns the driver if another vehicle is approaching rapidly from behind.

As shown in the illustration, the light illuminates when a vehicle is approaching, and flashes when the driver uses the turn signal to indicate a change of lanes in dangerous circumstances.

Lexus focuses on safety

The new LS 460 flagship limousine from Lexus has (among many other features) LED brake, tail and license plate lights, a thin profile-integrated LED high-mount stop lamp, and LED interior lighting with spot-lamp illumination in front and rear.

Crash me if you can - Lexus LS460
However, a more unusual application for LEDs is the vehicle's Driver Monitoring System, designed to warn of dangers ahead if the driver takes his or her eyes off the road.

The system comprises a CCD camera mounted on top of the steering column along with six infrared LEDs. When the car starts up, the system plots the position of the driver's facial features and uses these as a reference to monitor head movements when the driver looks from side to side.

If an object is detected in front of the vehicle while the driver's head is turned, a warning light and buzzer are activated, and the next step is to briefly apply the brakes.

The car also has an Advanced Obstacle Detection System, which uses information gathered from both a millimetre-wave radar system and an infrared detection system. The infrared system has a twin-lens camera located at the top edge of the windscreen, which detects IR radiation reflected from objects up to 25 metres distant. The near-IR radiation is emitted from dedicated units in the car's headlamps.

More in Indoor Lighting