Abstract： The cornea has complex biomechanical properties such as anisotropy, nonlinearity and viscoelasticity. Corneal biomechanics plays an increasingly important role in the diagnosis and treatment of corneal diseases thanks to development in relevant basic and clinical research. There is a significant difference in mechanical properties between in vitro and in vivo corneas. Exploring methods to measure in vivo corneal biomechanics is of direct significance for the diagnosis and treatment of corneal diseases. At present, both of the two main in vivo measurement instruments, ocular response analyzer (ORA) and Corvis ST, only provide the biomechanical parameters of the whole cornea, failing to reveal local characteristics of corneal material properties. The Brillouin microscope focuses on corneal tissue with a low-power, near-infrared laser beam and determines the longitudinal modulus of the tissue by analyzing the return signal spectrum from the cornea, enabling in vivo and non-contact measurements of the biomechanical properties of various corneal regions. This paper summarizes the measurement principle and safety of the Brillouin microscope, and its comparison with other equipment and clinical applications.
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