Optimal preamplifier/drive configuration for Tuning Fork force signal detection
Abstract
Tuning forks are widely used in scanned force microscopy applications, shear force and atomic force. The tuning fork resonance is driven either electrically or mechanically, and the signal is detected with a preamplifier. The high impedance of the tuning fork combined with low signal levels can make signal detection difficult. In this poser we compare the signal to noise ratio for several different preamplifier/drive configurations-- current vs. voltage feedback as well as electric vs. mechanical drive. We find that a guarded voltage preamplifier gives the best signal to noise ratio, however, an electrically driven current preamplifier provides a simpler construction with only a 25reduction in signal to noise ratio on average.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MAR.R1171J