Anisotropic mechanical response of carbon fiber under the optical force of a tightly focused laser beam

The integration of bended carbon fiber into optical waveguides demonstrates potential for applications such as grip strength sensors and redirecting the light path. In this study, we investigated the anisotropic mechanical response of carbon fiber subjected to the optical force generated by a tightly focused laser beam. We used optical tweezers to apply a controlled optical force for bending the carbon fiber without inducing structural damage or fracture. This method enables precise manipulation of fiber while maintaining its structural integrity. Additionally, the bending mechanism including the bending moment, bending stress, and shear force were proposed on the basis of optical tweezers, which provide a non-invasive way to control a bending process. This approach may offer a promising route for future development of grip strength sensors by enabling large, detectable changes in light intensity through integrated bent carbon fibers.