Note: Lateral force microscope calibration using multiple location pivot loading of rectangular cantilevers

This note outlines a calibration method for atomic force microscope friction measurement that uses the pivot method of [Bogdanovic , Colloids Surf. B 19, 397 (2000)] to generate optical lever sensitivities for known torque applied to rectangular cantilevers. We demonstrate the key calibration parameter to be a linear function of the position at which it is determined along the length of the cantilevers. In this way the optical lever system can be calibrated for cantilever torque by applying loads at locations along the length of a cantilever, away from the integrated tip, so that issues such as tip damage or interference can be avoided.