attocube's interferometric displacement sensors IDS and FPS (offering 1pm resolution and 10MHz bandwidth) are now available with new sensor heads. The existing portfolio already includes various options, each one optimised for specific measurement tasks: ultra-compact sensor heads (Ø 1.2 mm) for the use in very confined spaces; versions designed for easy alignment or enabling measurements on a wide variety of materials (glass, aluminum, ceramic etc.).

Two new heads have recently been added to the portfolio: The D12/F2.8 is designed for highly sensitive surface measurements offering a spot size of 2μm at a working distance of 2.8mm. Due to its sophisticated design, the M12/C7.6 completely eliminates signal intensity peaks even over large distances of up to 5m, and is therefore the perfect choice for long range measurements.

The advantage of both sensors lies in the highly flexible usage of their fibre-based sensor heads: the simple plug-and-play nature allows for various set-up configurations and the exchange of sensor heads within seconds. 

The company has also released the ECU (Environmental Compensation Unit), the first interferometer compensation unit providing fully automated air refractive index correction down to the subppm range.

When performing interferometric measurements in ambient conditions, air refractive index fluctuations can be a limiting factor: variations in surrounding pressure, temperature, and humidity can cause measurement inaccuracies in the tens of parts-per-million (ppm) range.  

When connected to the IDS interferometer, the ECU automatically detects the absolute sensor/target separation, calculates the actual air refractive index, and compensates any incremental measurement. In addition, the environmental are recorded and stored for future reference.