Phase shifters are used in laser measurement to align optical path
lengths. These move optics in the range of a wavelength, which
corresponds to an adjustment range of less than one micrometer. It is
crucial for the alignment to take place quickly and in a stable manner.
For the new S-303.BL phase shifter, PI (Physik Instrumente) replaces
classic piezo ceramic PZT actuators (made of lead titanate - lead
zirconate) with pico actuators made of a crystalline, lead-free
material. These pico actuators are characterized by a particularly high
linearity, so that precision positioning is also possible in open-loop
operation. With a travel range of 0.3 micrometers, they achieve a
precision of 6 nanometers, which corresponds to a linearity of 2%.
In comparison to classic piezo ceramics, however, pico actuators have a
smaller displacement. Ideal fields of application are therefore
wherever high dynamics, short travel ranges and high precision
requirements are necessary.
Open-loop operation does without the use of a position sensor in favor
of the system bandwidth and costs. This simplifies the mechanical
structure and the electronic control; servo cycle delays do not occur.
The S-303.BL is thus a precise yet dynamic drive for optics in the
range of a wavelength.
More information at www.physikinstrumente.de/