Multi-beam light source device and optical scanning apparatus using the multi-beam source device

A multi-beam light source device comprising:

• a plurality of light emitting sources adjacent to each other, each of said light emitting sources emitting a light beam substantially in the same direction;
• a half mirror for splitting each light beam emitted by said plurality of light emitting sources into at least two split light beams;
• a light converging unit for converging one of said split light beams at a predetermined focal point with respect to a first direction corresponding to a direction in which said plurality of light emitting sources are aligned, said one of the split light beams converging at a position other than said predetermined focal point with respect to a second direction perpendicular to said first direction;
• a plurality of light receiving elements, positioned at said predetermined focal point of said light converging unit, for receiving said one of the split light beams, said plurality of light receiving elements corresponding to said light emitting sources, arranged in said first direction so that each split light beam which corresponds to the respective light beam emitted by said light emitting sources is received by corresponding one of said light receiving elements;
• and
• a controlling circuit for controlling an output of said plurality of light emitting sources in accordance with an amount of light of said one of the split light beams received by said plurality of light receiving elements so that said each light beam emitted by said light emitting sources is controlled separately.

An optical scanning apparatus comprising:

• a multi-beam light source device comprising a plurality of light emitting sources adjacent to each other, each of said light emitting sources emitting a light beam substantially in the same direction;
• a half mirror for splitting a light beam emitted by said plurality of light emitting sources into a first split light beam and a second split light beam;
• a light converging unit for converging said first split light beam at a predetermined focal point;
• a plurality of light receiving elements, positioned at said predetermined focal point of said light converging unit, for receiving said first split light beam, said plurality of light receiving elements corresponding to said light emitting sources;
• a controlling circuit for controlling an output of said plurality of light emitting sources in accordance with an amount of light received by said plurality of light receiving elements so that said each light beam emitted by said light emitting sources is controlled separately;
• a deflecting mirror for deflecting said second split light beam;
• a collimator lens positioned between said multi-beam light source device and said deflecting mirror;
• an aperture positioned between said collimator lens and said deflecting mirror;
• and
• a pair of cylindrical lenses, positioned between said collimator lens and said deflecting mirror, which cylindrical lenses have a curvature only in a direction corresponding to a direction perpendicular to a primary scanning direction of said optical scanning apparatus.