Bestech Australia presents optoNCDT 2403 confocal chromatic displacement measurement sensors, from Micro-Epsilon, Germany.
With an external diameter of 8mm, the displacement measurement sensors are compact and slim and similar to the range of miniature sensors (optoNCDT 2402). However, due to its larger digital aperture, confocal displacement measurement sensors can receive more reflected light than the smaller, 4mm diameter version.
Polychromatic white light is focused onto the surface of the target 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. Confocal displacement measurement systems also allow for the one-sided thickness measurement of transparent materials.
An ancillary lens is positioned before this optical system in the sensor, and due to its greater divergence, the so-called relay lens enables significantly more reflected light to be detected from the target. This is especially beneficial if the displacement measurement 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.
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 displacement measurement sensor, which means it can be placed further away from the measurement object.
Typical applications for displacement measurement sensors include installations in which space is restricted and where the required base distance is not ideal for reflecting target surfaces. For the launch, four displacement measurement sensor versions are available with measuring ranges between 0.4mm and 10mm and axial beam output.