Free guide to laser displacement sensors

Micro-Epsilon's optoNCDT laser-based displacement sensors suit a variety of industrial applications, from parts measurement, car body positioning in assembly lines and surface contour measurement, through to flatness measurement of integrated-circuit (IC) pins, roundness measurement of catalytic converters and thickness of sheet or web materials.

The sensors benefit from high speed and high resolution, provide a wide measurement range (large stand-off) and offer non-contact, wear-free sensing. Using the laser triangulation principle, the sensors operate with a laser diode that projects a visible light spot onto the surface of the measurement target. The light reflected from the spot is imaged by an optical receiving system onto a position-sensitive element. If the light spot changes its position, this change is imaged on the receiving element and evaluated.

Difficult target surfaces

Laser-based optical displacement sensors measure from a large distance to the target using a small spot size, which enables measurements to be made on very small parts. The large measurement distance, in turn, enables measurements to be taken against difficult target surfaces such as hot metals. Furthermore, the non-contact principle enables wear-free sensing. The laser triangulation principle is also suitable for very fast measurements with high accuracy and high resolution.

For demanding applications, Micro-Epsilon's optoNCDT 2200 range is claimed to be unbeatable, with the linearity and resolution representing the limits of laser triangulation sensor technology today. High measuring rates, extreme accuracy and constant signal stability are carried out at full speed without any signal averaging.

At the other end of the scale is the optoNCDT 1300, a very compact, low-cost sensor with integral electronics that is suitable for standard industrial and high-volume OEM applications. Due to the sensor's compact design, integration into tight spaces is possible - for example, on machines or in automation applications. Even though it is low cost, this sensor is still said to offer higher resolution than competing sensor products on the market.

Digital and analogue sensors

Chris Jones, Managing Director at Micro-Epsilon (UK), comments: "We are supplying UK customers in a diverse range of industries with our digital and analogue optoNCDT sensors. If required, we can customise a solution for an OEM application and we can provide a complete range of accessories, including digital processing and readout units, protective housings for harsh environments, set-up and configuration software and PCI interface cards that enable the customer to synchronise the acquisition of multiple sensor signals and an encoder. We have now gained an enviable reputation for specialising in high-accuracy thickness measurement applications and in high-speed, in-process, laser-based displacement measurement and inspection."

Another specialist application area for the optoNCDT sensor is in direct reflecting targets such as mirrored objects, glass or highly polished metals. Micro-Epsilon's optoNCDT 1700(001) sensor is suitable for these types of applications, compensating for the high intensity of the reflected light by using patented, high-speed software algorithm that dramatically reduces signal noise. Due to the algorithm's high processing speed, the sensor also measures with the same accuracy on dynamically changing surfaces. Furthermore, the unit size is identical to the standard optoNCDT 1700 Series and so is useful for integrating in restricted spaces.

For more information on Micro-Epsilon's optoNCDT range of laser-based displacement sensors, visit the company's website.