There is provides a wavelength conversion apparatus for converting a wavelength of input signal light and for outputting output signal light of the converted wavelength. The first frame is formed in a shape of a plate. The electricity collector is provided with a main plate joined to the bundles, a rib plate bent from the main plate and extending outward of the battery pack, a mounting plate extending along the inside of the battery lid, and a connecting plate bent from of the mounting plate and extending toward a bottom surface of the battery pack. One or more of the sections include bristles that extend to varying lengths from the base to form a contact surface that inclines or declines relative to the base. The flash memory device is byte-erasable and bit-programmable.