The apparatus 1, further comprising an amplitude detector that detects an amplitude of {HEAD ~ the torsional motion} of {TAIL ~ the cantilever} 
of
The apparatus 1 , further comprising an amplitude detector that detects an amplitude of { HEAD ~ the torsional motion } of { TAIL ~ the cantilever }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL