Queensgate Instruments Digital Piezo Translator (DPT) nanopositioning actuators

Queensgate Instruments’ Digital Piezo Translator (DPT) series of actuators incorporates capacitive sensors in order to deliver precise positioning and rapid settling. The actuators can be implemented in a wide variety of applications, including interferometry, semiconductor mask-wafer chuck alignment, beam alignment, cavity tuning, adaptive optics, scanning probe microscopy and a multitude of different metrology tasks.

The DPT-D series is said to feature best-in-class positioning performance, while the more compact DPT-E is a low-voltage replacement for the previous generation DPT-C series. Air and ultrahigh-vacuum variants are also available.

The units’ Super-Invar construction provides good thermal properties (with a thermal expansion coefficient of 0.25 nm/K), which enhances position stability. Position resolutions down to 0.09 nm (RMS) are offered as each unit delivers <2 ms response time, 0.5 nm (RMS) repeatability. They are able to move loads of up to 60 kg across their entire closed-loop range, with closed-loop ranges from 20 to 110 μm.

DPT devices benefit from a built-in calibration function derived from the Queensgate ID chip arrangement. The ID chips store calibration data on the actuator itself and thereby facilitate plug-and-play operation with the digital controller. Controllers and actuators can be interchanged as required, avoiding the need for recalibration, which is important when the actuator is incorporated into a mechanism or is inaccessible.

Accessories include various end pieces, mirror holders and mounting blocks. An operational temperature range of -30 to 80°C is supported, but higher temperature variants can be offered.