Distance Measurement

Absolute and contactless

The interferometric measuring technology used in the FDM Series delivers nanometer accuracy and absolute distance values of almost any type of surface. Combined with our miniaturized probes, the system has a wide range of potential applications, including within very small cavities.

High-precision position measurement

In the field of precision manufacturing, feeding and orienting workpieces requires the component’s position to be determined with high accuracy. Tolerances are in the micrometer range, and fionec’s fiber-optic distance measuring systems deliver highly accurate absolute position values.

Expansion, drift and vibration

Mechanical, thermal and dynamic effects on components and machine tools can have a tolerance-critical impact on quality and functionality. The distance-measuring sensors of the FDM systems allow changes to be detected in terms of nanometers and quickly compensated for as necessary.


The FDM-1 class measuring systems are characterized by especially high accuracies. Within a measuring range of 80 µm, the typical standard deviation is less than 3 nm.
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The FDM-2 class measuring systems feature a wide measuring range of 1 mm and high accuracies of under 10 nm. The system affords a great deal of flexibility for custom applications.
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The advantages

  • Nanometer precision

    The fiber-optic sensor measures distance, position and changes of position with an accuracy of just a few nanometers. Automatable calibration routines ensure that the values generated are reliable and consistent.

  • Absolute measurement values

    fionec’s fiber-optic distance-measuring systems deliver absolute values using the principle of white light interferometry. In contrast with laser interferometers, the measured value is not lost when the measuring process is interrupted with FDM technology.

  • Maximum flexibility

    The measured values are acquired and transmitted via fiber-optic cables. This makes it possible to place the probe and evaluation unit at almost any distance from one another.

  • Measuring in the smallest of cavities

    The probes can be miniaturized down to a diameter of 50 µm. This makes it possible to perform measurements in very tight spaces.

  • Fully automatable

    The fiber-optic distance measuring systems can be easily integrated into existing processes and machines using the integrated interfaces. This allows for component positions to be determined during production, including at production speed.