| 摘要 |
<p>PROBLEM TO BE SOLVED: To compensate electricity consumption by efficient use of a light source as well as external light and allow an electronic apparatus using a secondary battery to be used for longer continuous time, with a simple configuration.SOLUTION: A back surface of a housing 201 of a mobile phone has a light source 204, a conductive key sheet 203 having a plurality of operation keys 206, and a solar cell 202, which are stacked and arranged. Each of the operation keys 206 is exposed outside through a through-hole 208 of the solar cell 202 and a through-hole 207 of the housing 201. The key sheet 203 guides light from the light source 204 and light from the external space of the housing 201 to the solar cell 202, and guides light from the light source 204 to the operation keys 206. The solar cell 202 receives the light from the light source 204 and from the external space of the housing 201 through the key sheet 203 and converts the same into an electric energy to be charged to a secondary battery.</p> |
