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Proven effective in numerous applications, our PMD distance sensors of the OGD series are highly versatile problem-solvers. The photoelectric sensors deliver stable and accurate results even in challenging environments.

Find out which key benefits the OGD sensors from ifm offer. In the following, we explain what reflectance is and how time-of-flight measurement works. The application examples listed below illustrate how you can use the OGD to your advantage.

What is reflectance?

The reflectance indicates the percentage of luminous flux reflected by a surface. The brighter the surface, the higher the reflectance: A white wall reflects up to 85 percent of the light, bright wood panelling only up to 35 percent.

What are the advantages of time-of-flight measurement compared to conventional triangulation sensor technology?

  • The OGD sensor measures distances with PMD technology, a time-of-flight method that detects objects much more reliably than, for example, CMOS sensors. The sensor especially demonstrates its strength when detecting shiny surfaces or black surfaces with low reflectance. While the OGD can still detect the objects, an CMOS sensor will no longer provide a result.
  • Even multi-coloured objects such as chipboard or pieces of meat are reliably detected thanks to the PMD technology.
  • Background suppression and laser light make the OGD extremely reliable even if exposed to external interference such as movements and reflections.
  • The sensor can detect objects even at extreme alignment angles, while a triangulation sensor must be aligned at an angle of 90° to the object.

What are the advantages of OGD sensors compared to standard sensors?

  • The OGD eliminates the duplicated effort of mounting and wiring both a transmitter and a receiver (or reflector) - the total cost of your solution can be significantly reduced.
  • The window function, a user-definable object detection range, makes it possible to process objects of different sizes with a single device. Even with changing production lines, there is no need to reconfigure the sensors.

OGD Long Range in the field: conveying and packaging industry

Application example 1:
Verification of the correct sealing of packages

Based on the reflectance value, the OGD Long Range registers whether ready-to-ship packages have been properly sealed with adhesive tape. A signal can be output via IO-Link to feed sealed packages into the further shipping process. Even transparent adhesive tapes are reliably detected by the sensor.

Please note that the reflectance value can vary significantly due to deviations in materials or angles. Thus, tests under real operating conditions and a 90° alignment to the target are recommended.

Application example 2:
Two-stage conveyor belt stop function

Background suppression is yet another advantage the OGD provides. The feature comes in handy when implementing a stop function at the end of a conveyor belt. Reflections from metallic surfaces do not affect the sensor, which also reliably detects objects of different colours. The first switch point triggers a speed reduction of the belt. When the object reaches the second switch point, the belt is stopped.

Advantage: Replacing the two units which are typically required for a light barrier, the OGD helps to reduce the purchase, installation and wiring costs. In addition, it can be used in almost any mounting situation, as it can be aligned to the belt at an oblique angle.

Application example 3:
Monitoring the presence of seals in lids

The OGD can detect whether a seal is present in a packaging lid. Based on the reflectance value, it can also detect seals of different colours. This reduces the risk of entire product batches being spoiled in filling plants.

Parameter setting during operation possible via IO-Link, can be used for changing production lines

Food industry

Application example 1:
Object detection in product handling

The OGD Long Range reliably detects objects even in unfavourable lighting conditions. It does not even miss reflective or wrinkling materials such as foils, which also often come in colourful or dark designs.

The sensor detects dirt on the lens through the reflectance value via IO-Link and alerts the operator about cleaning. This reduces faulty measurements and increases process reliability.

In food industry processes, IP 69K and the use of plastic instead of glass are frequently a prerequisite. The OGD has IP 67 and a glass lens, but thanks to its long range it can also be placed outside the risk area in some applications.

Application example 2:
Production monitoring and product evaluation

In food processing applications, the OGD Long Range is used to monitor the handling technology. At the same time, it can be used for product evaluation. For example, pieces of meat have different colours and contrasts due to fat layers and bones and can therefore be evaluated in terms of quality and product size.

Metal working and mechanical engineering

Application example 1:
Level monitoring of oily liquids

The OGD Long Range can be used to detect levels of coarse-particle or not fully light-transmissive liquids such as oils or (foam-free) coolants. The sensor detects the distance to the surface, enabling exact level determination in the tank.

OGD Precision in the field: error proofing

Application example 1:
Quality assurance during production

The OGD Precision performs precise and reliable inline quality checks to monitor the correct position, orientation and quality of small shiny or black components such as O-rings or toothed wheels.

Assembly errors such as missing O-rings of 5 mm thickness or more are detected. This error proofing process during production and before final quality checks minimises the risk of costly consequential damage such as plant downtimes or batch failures. At the same time, the inline quality check contributes to long-term and efficient quality assurance. The earlier errors are discovered, the lower the consequential costs are and the sooner improvements can be made.

At an oblique angle, however, the reflectance value of the OGD is no longer reliable since too little light might be reflected.

Robotics and handling applications

Application example 1:
Quality assurance in fully automated production processes

In the fully automated production of electronic devices, it is essential to ensure the presence and correct assembly of parts from different angles with precision and reliability. Here, the OGD is used for production monitoring of white goods or electronic components such as PCBs and other electronic devices.

Product overview - Distance sensors

Reliable optical distance measurement with high ranges

The photoelectric sensors deliver stable and accurate results even in challenging environments.