Confocal displacement, distance, position and thickness sensors


The confocal measurement principle is designed for high accuracy, non contact displacement distance and position measurement against any surface: solid, transparent, polished mirrored surfaces, low reflective matt surfaces and even liquids. If a surface is transparent, a one sided thickness measurement can be achieved with inbuilt correction for the material refractive index.

Quite often confocal sensors are selected when laser triangulation or other optical sensors are not accurate or stable enough on the surface being measured. In addition, confocal sensors have an extremely small spot diameter, typically a few microns and measure in the vertical plane, so do not suffer from shadowing of the reflected light. This also enables measurement into small bores and holes.

Almost all industries benefit from this measurement principle as it can be used in both R&D and in-process measurements. In particular, the semiconductor, micro lens, automotive part, medical, glass, and MEMS industries use this sensor technology in many ways. 

  • Excellent signal-to-noise ratio
  • Industrial-grade controller
  • Extremely small and constant spot size
  • Almost surface-independent, also valid for mirrored and glass surfaces
  • Nanometre resolution
  • One-sided thickness measurement
  • Passive measuring system
  • Robust design

High precision displacement and distance measurement on practically all types of surfaces

The confocal chromatic measuring principle enables high precision displacement and distance measurements – on both diffuse and mirrored surfaces. Very small objects can be detected due to the small measurement spot size. Due to the axial beam path there are no shadowing effects. With the 90° version, geometrical features can be measured inside holes and recesses.

One-sided thickness measurement of transparent materials

The confocal chromatic measuring principle enables thickness measurements of transparent materials such as glass. The thickness value is detected to micrometre accuracy using only a single sensor. The controller provides an editable, expandable materials database. Material-specific parameters such as refractive indexes can be adapted using the web interface. Multi-peak measurements enable the evaluation of up to 6 peaks, which is how multi-layer objects such as laminated glass can be measured.

Controllers with high resolutions and high speeds

The confocal DT controllers provide an excellent signal-to-noise ratio enabling measurements at high accuracy and have been designed for industrial environments. The fast surface compensation regulates the exposure cycles in order to achieve high signal stability which is particularly for high speed scanning of surfaces with varying reflection characteristics. Interfaces are RS422, Ethernet, EtherCAT or Analogue Output.

Fastest measuring rates for dynamic measurement tasks

The confocalDT IFC2471HS controllers offer with 70 kHz the highest measuring rate in the world and are frequently used for dynamic monitoring tasks. In order to adapt the illumination to the respective surface, the controller dynamically regulates the exposure of the CCD line. This exposure control compensates for reflectivity changes of the measurement object much more faster than the conventional light source control. This is how the confocalDT controllers provide outstanding measurement accuracy with high measuring rates and changing surface colours.

Ultra-small light spot detects finest details and structures

Confocal sensors from Micro-Epsilon generate the smallest of light spots <3 µm due to their high Numerical aperture (NA). Therefore, the finest details and structures can be detected reliably.

Call 0151 355 6070 or email Micro Epsilon to help select the right product for your application.

Extremely large tilt angle

The confocalDT IFS sensors tolerate a large tilt angle up to 48°. Therefore curved and structured surfaces can be detected reliably to generate stable signals.

Ready for vacuum

The confocalDT sensors consist of passive components and do not give off heat. Particularly for use in vacuum applications, Micro-Epsilon offers sensors, cables and accessories which are suitable for the according specification.

Ease of use via web interface

Due to a user-friendly web interface, the entire configuration process is carried out without using any additional software. The web interface can be accessed via Ethernet and provides set up and configuration options. Materials are stored in an expandable materials database.


No.1 Shorelines Building
Shore Road
CH41 1AU
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+44 151 355 6070
+44 151 355 6075