A second region (12) composed of a plane is formed around a first region (11) having a lens function, and a third region (13) is formed between the first region and the second region. A protection film (24) is formed on the surface of the first region 1. The first region is protruded relative to the second region, the third region is formed throughout the rim of the first region 1, and the surface of the third region is recessed relative to a virtual curved surface (11a) that is a curved surface along the surface shape of the first region being extended to the second region. Consequently, it is possible to form throughout the first region a protection film having a surface shape that substantially matches the surface shape of the first region.