Optical force sensing can detect microscopic surface movement, offering a route to controls hidden behind metal, glass or decorative trim without relying solely on capacitive touch.
SOURCE ANNOUNCEMENT: 8 October 2026 | ams OSRAM
A new role for the surface
ams OSRAM’s 8 October technical story on optical force sensing describes a useful development in human-machine interaction: the surface itself can act as a control, even when it appears to be an uninterrupted piece of metal, glass or another decorative material. The company’s AS7160 analogue front end can read up to eight optical sensing points in parallel, while the system is described as detecting surface movements as small as 0.22 micrometres. That is a sensitivity claim for the sensing architecture, not a statement that a complete automotive switch has passed qualification.
How light detects pressure
The operating principle is optical rather than capacitive. A compact emitter sends pulses of light towards a nearby surface; a photodetector measures the reflected signal. Pressing the material
produces a minute deformation, changing the reflected light and allowing the electronics to infer the applied force. The approach can distinguish levels of pressure and, with suitable infrared-transparent materials, can also support touch or proximity interactions. This gives designers more options than a conventional on/off switch.
Why automotive interiors are interested
Vehicle cabins are full of awkward interfaces: glossy panels that show fingerprints, capacitive buttons that are difficult to use with gloves, and switch packs that interrupt otherwise clean trim. Force sensing offers a potential alternative. A driver could press a continuous surface and receive a deliberate tactile or illuminated response, while the control remains visually hidden at other times. In principle, the same surface could support both decorative lighting and functional input.
The difference between touch and intent
Capacitive sensing is good at detecting contact, but a driver often needs to distinguish an accidental brush from a deliberate command. Measuring force provides an additional signal that may help designers define more robust activation thresholds. It does not eliminate the need for haptic feedback or usability testing. A control can be technically reliable and still be hard to find or operate without looking away from the road.
The integration challenge
Optical force sensing must be tuned to the stiffness, geometry and finish of the cover material. Temperature, ageing, mechanical mounting and vibration can all change the way a surface deforms.
The engineering task is therefore a system-level one, involving trim design, electronics, calibration and validation. Its appeal is strongest where it can remove a conventional switch assembly while
preserving predictable operation and an elegant material surface.
A more deliberate interaction
A well-designed vehicle control needs to tell the occupant where it is, whether it has been activated and what action has followed. Hidden pressure sensing addresses only the middle part of that
sequence. A practical implementation could use a softly illuminated icon to reveal the target area, force sensing to confirm a deliberate press and a haptic pulse to acknowledge it. Each layer then has a defined job. Such a design could preserve the appearance of continuous trim while remaining usable in motion. The challenge is to calibrate all three elements together, so the control feels
dependable rather than mysterious.
The Lux View
The next generation of smart surfaces will need to do more than illuminate. It must also understand intent. Optical force sensing adds another useful layer to hidden-until-lit HMI:
a surface that can look passive, respond to pressure and give feedback only when a user deliberately engages with it.
Publishing information
Source and research links
PRIMARY SOURCE ams OSRAM – optical force sensing story, 8 October 2026
SUPPORTING SOURCE ams OSRAM – optical force sensing technical overview
https://ams-osram.com/innovation/technology/optical-force-sensing
SUPPORTING SOURCE Continental – hidden functional surfaces, design context