Optical microscope objectives (A) can be used to stimulate blended organic photovoltaic films, while AFM topography (B) and electrical current (C) maps are recorded. The conductive AFM tip can be placed at specific locations (circle, square, and triangle) for localized current-voltage characterization (D). Imaged with the MFP-3D-BIO AFM. Ref. D.C. Coffey, O.G. Reid, D.B. Rodovsky, G.P. Bartholomew, D.S. Ginger, Mapping local photocurrents in polymer/fullerene solar cells with photoconductive atomic force microscopy, Nano. Lett. 7, 738 (2007).