Space-saving high-performer: SICK’s next-gen miniature photoelectric sensor family W4S - Optical Experts sensors: Application-specific variants for unique challenges


Waldkirch, December 2023 – With the miniature photoelectric sensor W4S, which rounds out the versatile W4 product family, SICK presented the latest addition to its portfolio of innovative, next-generation photoelectric sensor families at the SPS 2023 (November 14 – 16, Hall 7A, Booth 340). Thanks to their compact but sturdy VISTAL housing with side scanning window, the sensors are especially well-suited for applications with limited space. The W4S Optical Standard segment, which includes photoelectric proximity sensors, retro-reflective proximity sensors and retro-reflective sensors, offers high ranges and switching reliability for a host of standard applications. In turn, the W4S Optical Expert sensors are specially designed for challenging tasks, e.g. detecting discontinuous, uneven, extremely flat, transparent, reflective or high-contrast surfaces. The W4S sensors’ high-performance Opto-ASIC digital filters ensure the reliable detection of optical interference in the operational environment and deliver likely the best ambient light suppression on today’s market – along with optimum availability and process stability. 

Together with innovative monitoring options, the user interface BluePilot – tried and proven in countless other SICK sensors – makes setting and monitoring the sensors child’s play and saves valuable setup time. An IO link and smart functions for sensor monitoring and diagnosis connect the sensors to the world of digitalized machinery and applications – which also goes a long way toward making them future-proof. All sensors in the W4S product family are available with an installation-friendly 1-inch hole slot and market-standard connectors. Accordingly, mechanical engineers and users who previously relied on other brands and miniature sensor families can easily switch to enjoy the higher performance of SICK’s next-generation slim, space-saving sensors.

W4S Optical Experts: Delivering perfect performance for challenging applications

In order to reliably address particularly challenging contexts, SICK has developed a range of application-specific W4S sensor variants – the Optical Experts. For example, there’s the DoubleLine sensor, which employs two line-shaped light spots to guarantee a consistent signal, even for objects with (bored) holes, recesses or uneven surfaces, or for objects on difficult surfaces, e.g. chain conveyors. In contrast, NarrowBeam sensors offer an especially focused beam and point geometry. This design yields high-precision background suppression and enables them to reliably detect pitch-black objects with a remission of less than one percent. And sensors with the ApplicationSelect feature are a real highlight among the Optical Experts. By integrating up to 32 incoming signals, they are extremely sensitive. This not only doubles their range, but also significantly reduces black/white shift and hysteresis. As a result, sensors with ApplicationSelect can more dependably be used in situations involving angled perspectives, low-remission surfaces and at large distances. A special algorithm in SICK’s proprietary fifth-generation ASIC is what makes this performance booster possible. 

The new W4S Multimode sensors are true allrounders: With two independent switching points for detecting objects at different distances, the option of setting different detection windows within the scanning range, background and foreground suppression for adapting to different operating conditions and object qualities, 2-point teach-in button for added detection reliability, and ApplicationSelect – thanks to a diverse range of features, the Optical Experts offer maximum flexibility. Depending on the operating mode, settings can be quickly and intuitively changed via the IO link or directly on the sensor using the BluePilot operating element concept: by selecting the mode, by pushing the teach-in button, or by using the push-and-turn mechanism.

W4S retro-reflective proximity sensors with Clearsense MultiMode help you “see through” the task at hand – for nearly any degree of object transparency. Opaque objects and semi-transparent materials like frosted glass can be just as reliably detected as transparent films and sheets of glass. In tear detection mode, the sensors can distinguish between a transparent film and an opening caused by tearing. Another special operating mode allows them to reliably detect transparent trays and bottles – even those filled with water. These sensors can be set just like the MultiMode sensors – and offer the same advantages for mechanical engineers and users who want to stock up on just one type of sensor that can offer a range of functions.

SICK is one of the world’s leading solutions providers for sensor-based applications in the industrial sector. Founded in 1946 by Dr.-Ing. e. h. Erwin Sick, the company with headquarters in Waldkirch, Breisgau near Freiburg ranks among the technological market leaders. With more than 50 subsidiaries and equity investments as well as numerous agencies, SICK maintains a presence around the globe. SICK has almost 12,000 employees worldwide and generated a group revenue of around EUR 2.2 billion in the 2022 fiscal year. Additional information about SICK is available at

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