Surface + Light = Function

A modern control element is there when you need it. But what about when you don’t? Then, it elegantly vanishes into thin air. While this has nothing to do with hocus pocus, it has a lot to do with infrared light – but let’s start at the beginning: “We at Marquardt had the idea of no longer seeing a control element as a classic function key,” explains Dr. Martin Goetz. “Instead, we wanted the control element to appear situationally, or, to put it another way, only when the user really wants to operate it.” The systems engineer gives a car interior as an example: when a hand approaches the glove compartment, a switch pictogram lights up on the smooth surface. When the virtual button is touched, the compartment opens gently. This feature can also be expanded – so that the compartment can be locked with a numerical code. Depending on the situation, it also only appears, when the glove compartment is closed. 

The new module is a true gentleman: distinguished and reserved, with a sleek appearance, and present when it matters. It makes you wonder – what technology is hidden behind the stylish surface? Dr. Martin Goetz smiles: “Strictly speaking, none, because the surface itself only serves as a kind of screen for our projection. There’s no need for any additional detection electronics on or below the surface.” To make this work, Marquardt works with infrared light (IR). While it’s invisible to the human eye, it proves to be an effective tool when it comes to measuring movements and distances. For instance, in the case of the glove compartment the approaching finger’s position is detected by evaluating the IR light, and the distance from the user interface is determined. This is how the system “sees” when the finger touches the control knob. The reflected IR light, and with it the information, is processed by a sensor and the desired function – in this case opening or closing of the compartment – is triggered. This technology creates a major advantage for manufacturers, that can use IR light to position functions on surfaces with limited room for electronic components, or where they are out of reach, e.g. on the floor.

These new control panels are suitable for in-car applications that are not constantly used while driving – such as the Start / Stop button, adjusting the exterior mirrors or seats, and opening the fuel cap or even the glove compartment. If the control element is no longer needed, Materials like wood, leather and high-quality fabrics can keep their clean appearance. Product Manager Stefan Ruf believes there’s method in this minimalism: “In both cars and kitchen appliances, the trend is moving toward clean surfaces without any visible functions. We’re developing the appropriate control elements for this purpose. They’re not overloaded with an excessive number of applications, but rather guide the user without imposing themselves.” Particularly in kitchens, Marquardt is thus addressing the needs of end consumers who’d like clear and simple control of the appliances. 

This technology can be projected outside of a vehicle as well, such as a symbol appearing on the road: the trunk opens when touched with a foot. Or a garage door that uses a GPS system to detect when a car is approaching. The control element in the cockpit could also be connected to a garage via Bluetooth, and only light up when the car moves towards it. There are also a wide range of possible applications for this technology in home appliances - including the fume extraction hood above the stove, a refrigerator, the washing machine, a boiler in the basement or the control station in the lounge. IR technology is also in demand in medical technology, because where there are special hygienic requirements, smooth surfaces are more than just aesthetically significant. This much is true of devices in the OR, the step adjustment of a nursing bed, or the position and light regulation of the dentist’s chair. Indeed, the easier the surfaces are to clean, the more difficult it is for germs that are harmful to health to thrive.  

For manufacturers, infrared light evaluation is far more affordable than a camera solution, not to mention a more an expensive color display or touch screen. Marquardt’s aim is to cut the module’s production costs by reducing it to the essentials, thus enabling long production runs. The technology, for which a patent application has now been filed, is also undergoing continuous further development, as Dr. Martin Goetz reports: “In the future, we want to display not just one but several pictures by using a kind of slide changer that can play through several pictures, so we can build a simple menu structure.” To ensure the technology can even be used in strong sunlight, Marquardt is also working on projection with different colors. This increases the applications’ contrast and visibility.

Taking customer requirements into account, the projection module is now being refined to market maturity. Meanwhile, Dr. Martin Goetz and his colleagues are working on further innovations. “A lot will happen in the field of light and lighting in the future, especially in terms of new products focusing on smart, situation-dependent lighting in car interiors. This will be a big issue, not least in autonomous driving.” In principle, the developers at Marquardt follow the approach that every surface can be a control element – and the way to get there is through light!