To expand the degree of freedom of designing by forming a solar cell on the reverse side of a clock dial.

A total of 25 solar cells 12 (each five solar cells vertically and horizontally) are formed on an alumina substrate 11 that is in 6 inch square and × 0.2 mm thickness. The alumina substrate 11 has a 50% visible light transmittance. The solar cells 12 are divided into four portions by a cross split line and four stages are connected in series. An indium tin oxide transparent conductive film with a film thickness of 1000 is formed on the substrate 11. Then, a photoresist is formed in an electrode shape by the photolithography process. Then, p-i-n type amorphous silicon lamination is formed by the plasma CVD method and the solar cell parts 12 are formed by the photolithography process and the reactive ion etching method. Then, a counter electrode that also plays a role of the reflection plate of incidence light to the solar cells 12 is formed. An epoxy resin where carbon black powder is mixed is applied to the entire batteries 12 with a film thickness of 50 μm for covering and is burned to form a protection film 13.