A precise laser for detection of tiny objects

ifm efector’s national product and brand manager, Glenn Thornton, spoke to Manufacturers’ Monthly about the company’s latest addition to the family of photoelectric sensors.


Photoelectric sensors are used in a variety of industrial processes, including packaging, manufacturing and componentry assembly – to discover the distance, absence, or presence of an object.

The global photoelectric sensors market size has been growing in recent year, with more companies realising the power of automation in improving efficiency in their manufacturing processes.

According to a recent report by the US-based Grand View Research consulting company, the global photoelectric sensors market size is expected to reach US$2.09 billion ($2.83 billion) by 2025.

The growing demand for photoelectric sensors is attributed to the rising penetration of Industrial Internet of Things (IIoT) and the numerous benefits offered by the sensors – including maximising asset utilisation, improving productivity, and enhancing work safety.

ifm efector’s national product and brand manager, Glenn Thornton is also of the opinion that an uptake in the use of photoelectric sensors in Australia is inevitable.
“With the way the markets are going, the companies will be forced to use automation to enhance their efficiency and productivity,” he told Manufacturers’ Monthly.

ifm, a global manufacturer of sensors and controls for industrial automation, has developed a new O6 laser sensor to complement its O6 sensor family. The new O6 laser features a background suppression system that is colour-independent at 100mm range. This enables the laser sensor to detect tiny objects where conventional red light sensors reach their limits.

The laser is also equipped with IO-Link functionality, making it possible to automatically parameterise the sensors, diagnose plant states and transmit measured values without loss.

“The new O6 laser sensor has a very fine and uniform light spot, which enables it to provide precise detection and consistent laser alignment,” Thornton said.

The O6 Wetline family

ifm first introduced the O6 Wetline photoelectric sensor series about four years ago, growing the product suite over time.

The small rectangular design of the O6 was specifically designed for wet areas in the food industry. The stainless steel body offers the protection rating IP68/69K that is particularly suited to harsh wet environments in food production such as dairies, breweries and abattoirs.

ifm followed these product series with a new O6 range released in 2016 in a plastic body – offering the same optical performance as the lasers with the stainless steel body, but at a competitive price.

The new precise laser sensor with the 100mm detection range adds to the existing laser sensors in this family of products, which also include a through-beam laser with a range up to 15 metres and retro- reflective laser with a range up to 8 metres.

“The retro-reflective arrangement uses a reflector to bounce the inverted light beam back from the transmitter to the receiver. A through-beam arrangement consists of two sensors. One sensor acts as the power unit and sends the laser beam, while the other one acts as a receiver,” Thornton said.

With such a varied range, the need for consultancy services is apparent. “When the customers visit our service centres or approach us directly, we help them identify the best technology for their particular applications,” Thornton said. “We ask them questions to determine whether they need the sensor for packaging, manufacturing or parts assembly applications, to understand the challenges for mounting the sensors and to find out the required distances to the objects. Accordingly, we advise them on the suitable technology,” he said.

IO-Link opens up new perspectives

The O6 laser features IO-Link functionality, which is a worldwide open-standard protocol for connecting sensors and devices. Through this technology, a binary laser diffuse reflection sensor becomes a high-precision distance sensor. This creates new application possibilities, including length and height monitoring.

“The IO-Link technology allows for millimetre-scale accuracy, making the sensor suitable for measurements within the 100mm range,” Thornton said.

Precise distance measurement enables the sensors to detect the presence of very small parts, such as small seals, washers, screw heads, metal clips and electronic components.

IO-Link is a powerful, yet simple protocol, which enables smart connection of sensors
and substations to the control level. IO-Link uses standardised interfaces that work with all IO-Link technology. If a sensor fails, it can be replaced without interrupting the production line.

ifm offers a wide range of IO- Link enabled sensors, including capacitive sensors, flow sensors, level sensors, pressure sensors, optical distance detection sensors, and temperature sensors.

Using IO-Link also minimises the need for shut down of machines to change sensor parameters. IO-Link allows remote parameterisation without incurring unnecessary downtime.