Technology mitigates LED flicker for safer automotive image sensors

SmartSens Technology, a supplier of high-performance CMOS imaging systems, has released its proprietary LED Flicker Suppression (LFS) technology. With this technology implemented, SmartSens' CMOS image sensors can effectively mitigate the dangers that often accompany LED flicker, making AI-enabled Advanced Driver-Assistance Systems (or ADAS) and Autonomous Vehicles safer than before.

LEDs are providing a higher performance, longer life alternative to traditional lighting in automotive applications. However, because LED drivers often utilize Pulse Width Modulation (PWM) signals, LED lights actually "flicker" at frequencies imperceptible to the unaided eye. For CMOS image sensors that have even faster shutter speeds, the mismatch between exposure time and LED pulse could lead to sensors picking up inaccurate visual signals, creating safety concerns in automotive applications.

With autonomous vehicles globally attaining Level 4 and Level 5 capabilities, cars increasingly rely on CMOS image sensors making accurate readings to correctly assess road conditions, necessary for AI systems to compute optimal next steps. This means that automotive CMOS image sensors must adapt to modern traffic signal systems by being able to distinguish between the on and off states of LEDs.

To mitigate LED flickering, SmartSens is using its proprietary QCell technology to not only mitigate LED flickering, but also increase the sensor's sensitivity and dynamic range, making it ideal for dim or fluctuating lighting situations, such as the openings of carports and tunnels.

"LED Flicker Suppression is a feature that all automotive CMOS sensors should possess, but is in fact not so easy to achieve," said SmartSens CMO Chris Yiu, in a statement. "In the future, CMOS sensors that SmartSens produces for the automotive electronics market will all come equipped with LFS technology, upgrading our clients' systems to be much more adaptable – and safer."