Rear lamps have existed since very shortly after the dawn of the automobile. The first ones, like the cars they were attached to, were basic and addressed the need for nighttime conspicuity in a primitive manner. safety functions were progressively improved by adding new functions—reverse light, rear fog light—and more stringent requirements for the basic functions: larger lit areas, wider distributions of light, higher intensities. The introduction of LEDs with instant-on illumination and more stabilized beam has carried this trend forward. Regulation has also evolved to allow and then require high-mounted auxiliary stop lamps, emergency braking display, hazard warnings, and other suchlike. The still-optional adaptive rear-light systems seek to improve safety performance in difficult conditions.
Besides this important role for safety, rear lamps are currently considered as a priority design feature, and more precisely the most important element at the rear to express the signature of the car.
Design has in fact been the real engine for innovations at the rear in recent years and this will likely continue in the future.
Before the arrival of LEDs, the challenge was steep to be original. Bulb technology imposed severe design constraints. Nevertheless, engineers and designers are innovative, and figured out ways to have very homogeneous lit surface, a variety of unlit appearances (sometimes with colours totally different to those of the emitted light), perfect fit and finish, and other innovations with optical systems using reflectors, fresnel lenses, coloured internal filters, multicolour injection, new welding techniques, and other complex processes to fulfil these needs and wants.
The introduction of LEDs opened the gates to boundless opportunities by dint of compactness, low operating temperatures, pure colour, and the freedom to use as many LEDs as wished.
One of the most important new techniques is the light guide, either by tube or by surface, with so many abilities to produce thin, long, or decorated elements as in the Cadillac Lyriq shown here.
OLEDs recently joined in as an interesting addition, bringing new prospects for illuminated facets, as on this Audi Q5 tail lamp.
Thanks to this large spectrum of technical possibilities, the current trends from designers demands are orientated to thin lights, illuminated logos, full-width rear lamps as shown here on the Geely Xingyue, and precise internal decorations as on this Mercedes EQS.
Above all, the demand is to express a signature, and the tail function is the cornerstone for that specific function—whether or not the lamp is lit.
Animated light is another trend requested both by design and marketing. It is applied for turn indicators with a wiping effect, and more and more for numerous kinds of welcome scenarios profiting from the tolerance of regulation when the car is stopped.
In the foreseeable future, rear lamps play a central role in innovations for safer and more connected vehicles: rear lamps with displays, with road projection, perhaps with LiFi, will progressively morph from conspicuity devices to versatile communication tools, with the ability to provide granular messages to relevant traffic participants, including more and more autonomous vehicles.
Rear lamps occupy two of a vehicle’s four strategic corners, and sensors including cameras and radars will likely be increasingly integrated into rear lamps to offer optimal field of view and detection aptitude.
So, the future of rear lamps will prioritise style with unfettered imagination, while at the same time realising long-awaited features to enhance functional safety.