Fig. 1.

Azobenzene photoresponse and its force generation measured by a customized setup. (A) Chemical structures of the azobenzene compounds. (B) Photoresponse of the fixed azobenzene single crystals (the crystals correspond to the compounds in A; the direction of light irradiation is from the top for all crystals). (C) Cartoon showing the force-measurement setup used to track the deflection of the PDMS micropillar tips. (D) Displacement of the micropillar tips bent by azobenzene single crystals upon irradiation.