TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Conditions: The resin is used as sealing material (520) of electricity generating element (510) in manufacture of solar cell module. The resin is used as a transparent substrate (530) provided in the light-receiving surface side of electricity generating element, and transmitting light. The resin is used as protective film (540) formed on the transparent substrate provided in the light-receiving surface side of electricity generating element, and transmitting light.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The wavelength conversion material is prepared in an inert atmosphere by baking a mixture containing a silicon source and a carbon source, obtaining a composite powder containing nano silicon fine particles by quenching the gas produced by baking, and obtaining nano silicon fine particles from the composite powder. The nano silicon fine particles are obtained from the composite powder by immersing the mixed powder in an etching solution containing hydrofluoric acid, and etching the mixed powder. The etching solution optionally contains an oxidizing agent. A portion of silicon monoxide and silicon dioxide are removed from the mixed powder. The mixed powder is then immersed in a solution containing an oxidizing agent and hydrofluoric acid. Light having larger energy than the band-gap energy of silicon fine particles is irradiated to the composite powder immersed in etching solution. The hydrogen atom added to the surface of the nano silicon fine particles is substituted by an organic monomer group having a hydrophilic group or a hydrophobic group. In an oxidizing atmosphere, the composite powder is heated and nano silicon fine particles are obtained from the heated composite powder. The resin which dissolves in a solvent, and the nano silicon fine particles are added to the solvent while making the resin contain the wavelength conversion material.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The resin is thermoplastic or thermosetting.