摘要 |
PROBLEM TO BE SOLVED: To provide a light diffusion variable device capable of simply and reversibly changing a light diffusion state.SOLUTION: A light diffusion variable device capable of reversibly changing a light diffusion state includes: a light diffusion laminate; and a distortion adjusting part for adjusting a surface direction distortion of the light diffusion laminate and capable of inducing a surface buckling uneven structure in the light diffusion laminate. The light diffusion laminate includes: a substrate having flexibility; and a thin film layer provided on the substrate. A modulus of elasticity of a material of the substrate is 0.1 to 10 MPa, a modulus of elasticity of a material of the thin film layer is 0.1 to 100 GPa, a ratio (Ea/Eb) of the modulus of elasticity (Ea) of the material of the substrate to the modulus of elasticity (Eb) of the material of the thin film layer is 10to 10, a thickness of the thin film layer is 0.0001 to 0.1 mm, a thickness of the substrate is 0.3 to 20 mm, the surface buckling uneven structure is not less than 0.1 mm and not more than 10 mm in uneven spatial period, and its aspect ratio (groove depth/uneven spatial period) changes within a range of 0 to 0.3 according to a surface direction distortion adjusted by the distortion adjusting part. |