Fig. 1. Schematic diagram of spontaneous Brillouin scattering detection system and two-dimensional scanning method

Fig. 2. Measured results of Brillouin shift for water in a laboratory environment, with the gray area representing the 95% confidence interval. (a) Short-term Brillouin shift of water; (b) continuous 7 d Brillouin shift of water; (c) continuous 90 d Brillouin shift of water

Fig. 3. Lens of ex-vivo porcine eye. (a) Sample of lens in ex-vivo porcine eye; (b) detection of lens capsule in ex-vivo porcine eye; (c) detection of lens section in ex-vivo porcine eye

Fig. 4. Experimental detection spectra. (a) Brillouin spectrum of the lens capsule. (b) Brillouin spectrum of the lens section. (c) spectrum of Rayleigh signal

Fig. 5. Two-dimensional Brillouin shift and two-dimensional Brillouin longitudinal elastic modulus of the lens capsule of ex-vivo porcine eye. (a) Distribution of two-dimensional Brillouin shift; (b) distribution of two-dimensional Brillouin longitudinal elastic modulus

Fig. 6. Distributions of two-dimensional Brillouin shift and longitudinal elastic modulus of lens in ex-vivo porcine eye, and the Brillouin longitudinal elastic modulus distributions across different orientations in the nucleus-centered region. (a) Distribution of two-dimensional Brillouin shift; (b) distribution of two-dimensional Brillouin longitudinal elastic modulus; (c) Brillouin longitudinal elastic modulus distribution along the x-axis; (d) Brillouin longitudinal elastic modulus distribution along the y-axis