SmarAct's sensor heads offer a range of customizable reference mirror options, ensuring compatibility with diverse applications and precise measurement needs. Featuring an intuitive alignment process and robust design, they deliver exceptional stability for long-term, reliable performance. These advantages make SmarAct sensor heads ideal for high-precision environments demanding consistent accuracy and ease of integration.

Michelson interferometer configurations

The different Michelson Interferometer configurations provided by SmarAct enable seamless integration into any setup by adjusting the position of the reference mirror. The different options are shown below:

Standard

In the standard configuration of a PICOSCALE sensor head, the reference mirror is coated to one of the side surfaces of the beam splitter cube.

 

Front reference - look around the corner

As a variant, the beam splitter can be coated to the front surface of the beam splitter cube. This can be advantagous in setups with certain space constraints as the sensor head can "look around the corner".

External reference - differential measurements

Another variant of PICOSCALE sensor heads do not have a reference mirror at all. This is unique for Michelson interferometers and allows to perform differential measurements of two targets with several advantages. Please also see our pre-aligned differential measurement head: Read more...

 

 

SmarAlign window

The standard PICOSCALE C01 Sensor Head has one port of the beam splitter unused for interferometer purposes. Typically, this part of the beam splitter has a coarse grinding so that one can use it as a view port for alignment (see schematic). This view port we call SmarAlign window in the following.

When the pilot laser beam of the PICOSCALE is activated, the visible light can be used to trace the propagation path to the target mirror as well as its reflection back to the sensor head. If the reflected beam hits the sensor head, one can see two spots in the SmarAlign window. By fine adjustment of the tip/tilt angle of the sensor head, these two spots can be overlapped which means the two beams can interfere.

Alignment not good; two spots are visible Alignment good; only one spot visible

 

Advantages of Michelson Interferometers

Michelson interferometers offer exceptional precision and reliability by splitting and recombining light to measure smallest displacements, vibrations, and refractive changes with nanometer or sub-nanometer accuracy. Their versatility, non-contact operation, and ability to perform in demanding environments like UHV or cryo-temperature make them indispensable for applications in metrology, optics, and advanced research.

Learn more about the advantages compared to other technologies in this article: Advantages of Michelson interferometers compared to other architectures

 

Easy Alignment