The optical detector 7 converts {TAIL ~ the amplitude} of the cantilever represented by the reflected light into {HEAD ~ an electrical signal} 
The optical detector 7 converts { TAIL ~ the amplitude } of the cantilever represented by the reflected light into { HEAD ~ an electrical signal }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD