Optical cement, panel and substrate fitting method

The invention provides optical cement. The optical cement comprises a first surface, a second surface opposite to the first surface and a plurality of first strip-shaped sunk parts, wherein the penetration rate of the optical cement in a visible light range is greater than 80%; and the first strip-shaped sunk parts are arranged on the first surface. The invention furthermore provides a panel which comprises the optical cement and a substrate fitting method which carries out fitting by using the optical cement. By using the optical cement with a strip-shaped sunk structure, the bubbles are discharged along the strip-shaped sunk structure in the pressurizing process of substrate fitting, and the optical cement can be heated and pressurized, so that the optical cement deforms to tightly fit with the strip-shaped sunk structure.