Next time you look at your rearview mirror, take a second look. It could incorporate a number of different features. Matthew Beecham reports on how the humble rearview mirror has been transformed over the last decade into a high-tech electronic module.

"Ten years ago, rearview mirrors were only a combination of plastic housing and glass," said Ramon Guixa, director of Ficosa's rearview systems business. "Today, the vehicle mirror includes a lot of new functions, like blinker, power folding, electrochromic glass, vision cameras, etc. We recently just set up a joint venture with Omron Corp to develop and supply ADAS [advanced driver assistance systems] to the OEMs. We are currently working on integrating antennae into the exterior rearview mirror. We expect to be in production next year. By integrating antennae and a number of other functions into the mirror, we can achieve considerable production cost savings for the OEMs. Some OEMs are even talking about an assembly cost saving in the region of 20 - 30% due to our approach."

Tomorrow's mirrors, say manufacturers, will feature fog sensing/signaling modules, gas sensing, occupant sensing, sign detection, pedestrian detection, etc. While more and more features are being packed into rearview mirrors, embedded camera technology is developing quickly. "Automotive camera technology has developed at such a fast pace that we are now believe some vehicle mirrors could eventually be replaced with cameras in the next five years," said Alf Liesener, marketing manager, Visiocorp Group Services GmbH. "Although we not aware of any contract, it is our clear impression of what is going on in the market today. "The early designs could resemble a combination of mirror and camera technology into one exterior unit, providing the driver with some level of security they can still see something in their rear view. While we don't know exactly how this market will take shape, we do expect to see more cameras for diverse applications on vehicles in the future, some of them even providing images that are displayed on a screen in the dashboard. Backing-up cameras are in the market already today and we made the experience that you get used to the new rear view device very quickly - and appreciate the advantages. We also see numerous advantages of cameras used to replace exterior mirrors potentially leading to the same level of acceptance." Last December, Schefenacker Plc was renamed Visiocorp Plc. The company designs and manufactures rearview mirrors and camera-based environmental sensor technologies. Visiocorp's core competencies include the design and manufacture of exterior and interior mirrors, injection molding and paint technology, electric drives and integrated automotive lighting.

While consumer demand for such highly featured rearview mirrors shows no sign of abatement in Europe, the prospects in North America also look rosy. "There is a trend in North America and globally toward additional features in rearview mirrors," said Enoch Jen, senior vice president, Gentex Corp. "In 2007, 56% of our auto-dimming interior mirrors offered one or more electronic features. In the past, some of these primary features have been compass displays and telematics. Our two most recent features are SmartBeam and Rear Camera Display (RCD). So there continues to be an appetite for featured auto-dimming mirrors globally." Gentex's RCD mirror consists of a proprietary liquid crystal display device that shows a panoramic video view of objects behind the vehicle in real time. When reverse gear is selected, the display illuminates and automatically appears through the rearview mirror's reflective surface to give a clear image. The image is generated by a camera or cameras placed in a protected area at the rear of the vehicle. When a forward gear is selected, the display automatically disappears.

Meanwhile, in the US, there is currently pending legislation, entitled the Kids Transportation Safety Act of 2007 which passed in the US House of Representatives and was introduced into the US Senate on 19 December 2007. The Bill orders the Secretary of Transportation at the National Highway Traffic Safety Administration (NHTSA) to initiate rulemaking to revise the federal standard to expand the field of view on light vehicles in the US so that drivers can detect objects directly behind vehicles. The requirements may be met by the use of additional mirrors, sensors, cameras or other technology. "[The legislation] was signed into law by President Bush on 28 February 2008," said Connie Hamblin, corporate secretary and vice president, investor relations and corporate communications, Gentex Corp. "Automakers have until approximately 2016 to put some sort of rear back-up aid in their vehicles. The actual legislation reads 'rear visibility standard' and safety advocates say that, if you are talking about 'visibility', then it must feature a camera. Historically, NHTSA has been able to interpret the legislation rather broadly to provide automakers with a range of options. We think that NHTSA may allow a sensor-based system, such as a sonar sensor or radar sensor. If that is allowed, then it will probably be offered on the lowest 10 - 20% of the vehicle market. We think that other options could include camera displays embedded in either a rearview mirror, navigation screen or possibly another dedicated display. As far as camera-based applications are concerned, we think that the very high-end vehicles will likely already have a navigation system and could therefore display the image in the navigation screen. That would account for the top 10 - 20% of the vehicle market. We think that the middle portion of the market - maybe 50 - 60% of the vehicle market - could be very ripe to have an auto-dimming interior rearview mirror with a camera display."

Gentex's RCD mirror is currently offered as original equipment as a stand-alone option on four Ford and Lincoln programmes as well as on the Kia Mohave for the Korean market. Jen added: "The automakers that adopted our RCD mirror to date did that prior to any pending legislation. They felt that there was a consumer demand to warrant the product anyway. And now with this legislation in place, we expect the ramp-up of our RCD mirror will be faster than initially expected."

The popularlity of other rearview mirror features continue to grow. For instance, LED turn signals have quickly entered the vehicle market with no signs of slowing-up. According to Ficosa's Guixa, the power folding mirror market is also blossoming in Europe. He said: "In fact, it is exceeding our expectations. I would say that it has increased by more than 100% compared to three years ago. At this moment, we are strongly investing to increase our capacity to meet demand."

While the big manufacturers have the resources to push back the technical boundaries, some important advances are being made by smaller enterprises. For example, in terms of the novel use of alternative materials, US-based optical specialist VTEC Technologies has developed new materials and processes that make the mass manufacture of plastic exterior rearview mirrors economically feasible. Jeanne Housman, president and CEO, VTEC Technologies, explained the approach her company took: "VTEC's proprietary plastic first surface chrome rear view mirror uses acrylic, polycarbonate and other resin materials to produce a new chrome metallisation technology that meets and exceeds the auto specification for exterior mirrors, as well as the specification for all exterior and interior chrome components. Our first surface chrome plastic mirror called 'V-Chrome' with its superior abrasion resistance meets weatherability and durability standards for automotive exterior rear view mirrors." Housman says that V-Chrome plastic rearview mirrors do not exhibit any of the known performance limitations of ordinary plastic mirrors such as service life, image distortion or heat instability. "V-Chrome is a highly durable light plastic mirror with performance characteristics as robust as glass, while being more durable than glass as V-Chrome mirrors do not shatter or break."

See also: Global market review of automotive rearview mirrors - forecasts to 2014 (download)