A composite light blocking sheet includes a first surface layer, a second surface layer, an inside substrate layer and a central axis. The first surface layer has a first opening and a first outer surface connected to the first opening. The second surface layer has a second opening and a second outer surface connected to the second opening. The inside substrate layer has a substrate opening and is disposed between the first surface layer and the second surface layer and connects the first surface layer and the second surface layer. The central axis is coaxial with the first opening, the second opening and the substrate opening. More than 95% of the first outer surface has a first gloss being GU1, more than 95% of the second outer surface has a second gloss being GU2, and the first gloss GU1 and the second gloss GU2 satisfy specific conditions.