By Shannon Ghorbani, Mad City Labs Inc.
Mad City Labs has demonstrated the capability to repeatably achieve a one-picometer movement with a piezo nanopositioner, and to accurately resolve that movement. The ability to achieve such high precision for a positioning device is largely dictated by the position sensor — in this case, Mad City Labs’ PicoQ sensor. Achieving high precision with repeatability is only possible with closed loop feedback, meaning the sensor value is fed back into the control system to maintain a position. The position noise level must be exceptionally low so the stage can maintain that change in distances of a single picometer.
A critical element of this demonstration is that it was performed in ambient conditions, without a specially designed room or customized software. It can be accomplished by anyone with a combination of low sensor noise, low-noise electronics, and a high-resolution interface.