3M Brandishes Automotive Light Saber

Darth Vader had the light saber; 3M Automotive has the Precision Lighting Element (PLE).

Both devices produce a soft but bright shaft of white light, but 3M's product wasn't dreamed up in a Hollywood studio and it doesn't buzz like a beehive, either.

The St. Paul, MN, supplier of all things adhesive is diversifying its portfolio, and the PLE is part of a corporate initiative to push innovation deeper into the automotive sector.

Most automotive lighting applications require conventional incandescent bulbs, but light-emitting diodes are taking over because they last longer, are easier to package and offer creative design alternatives. They're more expensive, however.

For the PLE, 3M molds a flexible urethane tube that can be produced in thicknesses between 0.078 in. and 0.46 in. (2 mm and 12 mm). One LED is placed at each end of the tube.

The tube looks as smooth as a neon light, except for tiny grooves molded into the surface at 90-degree angles. When the LEDs are illuminated, those surfaces act as mirrors, reflecting the light within the tube and intensifying the brightness.

This series of reflections allows a tube up to 2 ft. (61 cm) long to be just as bright in the middle as it is at the ends.

“It can be tied in a knot, and it still provides illumination,” says Brian Pospy, business development manager at the 3M Automotive Market Center in Livonia, MI.

Intended applications include center high-mounted stop lights (CHMSLs), cupholders, headliners, map pockets and grab handles. 3M also wants to use PLEs as reading lamps, mounted behind front-row head restraints, for second-row occupants.

At a recent customer event, 3M displays its Viki III concept car, which is a Lincoln MKX cross/utility vehicle loaded with these lighting applications.

3M removed the standard incandescent CHMSL on the MKX, which employs six incandescent bulbs, and replaced it with one PLE light tube with two 1-watt LEDs at either end. Pospy says the advantage of the LED CHMSL is it requires less power and can provide additional illumination. Plus, it lights faster, alerting trailing drivers of panic stops more rapidly.

Also, the PLE CHMSL requires 0.75 ins. (1.9 cm) of packaging space, compared with 2.5 ins. (6.3 cm) for the conventional CHMSL.

Another innovation on the Viki III concept car is “Light By Wire,” which uses LEDs placed along a copper cable. The flexible configuration allows “target placement” of lighting wherever the customer wants it — in a cupholder, map pocket or footwell — for ambient accent illumination, without distracting the driver.

Target lighting is possible with conventional incandescent lights, but Pospy says they are prone to burn out. Most incandescent lights are good for 1,500 hours of continuous use, compared with 80,000 hours for LEDs, he says.

And LEDs can be price competitive with incandescent lights, “as long as we are able to be involved in the engineering of the product,” Pospy says.

The Viki concept car also features Advanced Light Control Film, which is placed inside display screens to reduce unwanted reflections and glare by redirecting light away from the viewer.

Likewise, 3M's Brightness Enhancement Film offers design freedom for locating display screens and removing the brow over instrument clusters.

Another clever innovation is interior trim film that looks and feels like real wood or metal, with grain or texturing. The films are durable and resist scratching.