Fluorescent image correlation for nanoscale deformation measurements

The fluorescence-based digital image correlation (FDIC) technique for the measurement of nanoscale deformation in materials using fluorescent nanoparticles, was illustrated. The characterization of the complex deformation fields generated around silica microspheres embedded in an elastomer under tensile loading was conducted and displacement resolutions of 20 nm were obtained over a 100 × 100 μm field of view. The operational limit of the FDIC technique were determined through a series of rigid-body translation and uniaxial tension calibration experiments. The results show that FDIC provides a robust methodology for full-field, noncontact, real-time deformation measurements with nanoscale resolution.