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