shown that is proportional to the deflection of the cantilever the entire optical detection system is enclosed in a rigid stable capsule 40 the capsule is attached to the frame of the instrument 44 via flexible couplings or flexures 41 and 42 these couplings allow the capsule 40 to translate vertically with respect to the frame of the instrument 44 a piezo stack 43 is used to effect the translation and our improved lvdt sensor with the moving primary 15 attached to the moving capsule and the stationary secondaries 3 and 4 attached to the fixed frame of the instrument provides positional information fig1 shows the importance of the lvdt sensor in making force measurements both panels show a force curve made using a si cantilever nanosensors mesp over a mica surface in air panel a of fig1 is a plot of the cantilever deflection vs the voltage applied to the piezo the light trace 45 shows the approach curve and the dark trace 46 the retraction curve the adhesion between the tip and sample is evident in the retraction curve as is the u201c snap off u201d point 47 at approximately 5 5 volts as will be noted the contact portion of the approach and retraction curves do not have the same slope this can be explained as some sort of viscoelastic behavior of the tip or the sample or both however it can also be explained as an artifact of piezo hysteresis leaving.