BESTECH Australia has released the optoNCDT 2403 confocal chromatic sensor for displacement measurement from Micro-Epsilon, Germany.
The optoNCDT 2403 has an external diameter of 8mm, similar to the optoNCDT 2402 range of miniature sensors. However, due to its larger digital aperture, the sensor can receive significantly more reflected light than the smaller, 4mm diameter version.
Polychromatic white light is focused onto the target surface by a multi-lens optical system, which disperses it into a series of monochromatic light. A specific distance to the target is assigned to each wavelength by a factory calibration. The light reflected from the target surface is then read by a spectrometer which detects and processes the spectral changes.
This allows for displacement measurement in limited space, with sub-micron accuracy and extreme spatial resolution. The confocal displacement measurement system also allows for the one-sided thickness measurement of transparent materials.
In the new sensor an ancillary lens is positioned before this optical system, and due to its greater divergence, the so-called relay lens enables significantly more reflected light from the target to be detected. This is particularly beneficial if the sensor has to be tilted or if the target is non-planar, so that the reflected light is only reflected back by an angular deviation in the sensor. In this way, due to its larger opening angle, the optoNCDT 2403 can perform more stable displacement measurements on poorly reflecting and tilted surfaces than the optoNCDT 2402. The relay lens also increases the base distance of the sensor, which means it can be placed further away from the measurement object.
Typical applications for the this new displacement measurement sensor are installations in which space is restricted and where the required base distance is not ideal for reflecting target surfaces. For the launch, four sensor versions are available with measuring ranges between 0.4mm and 10mm and axial beam output.