Multi-beam scanning method, apparatus and multi-beam light source device achieving improved scanning line pitch using large light emitting points interval

A multi-beam scanning apparatus comprising:

• n number of semiconductor laser array units, each of the n number of semiconductor laser array units having m number of light emitting points, where n is greater than 1 and m is greater than 1;
• at least one coupling lens arranged to couple beams emitted from the light emitting points of the laser semiconductor array units;
• a beam synthesizing device arranged to synthesize the coupled beams to obtain m×n number of beams;
• and
• an optical deflector arranged to deflect the m×n number of beams at substantially the same time such that the deflected beams are impinged on a scanning surface,
• wherein the light emitting points of the semiconductor laser array units are inclined in a direction that coincides with the sub-scanning direction.

An image forming apparatus comprising:

• n number of semiconductor laser array units, each of the n number of semiconductor laser array units having m number of light emitting points, where n is greater than 1 and m is greater than 1;
• at least one coupling lens arranged to couple beams emitted from the light emitting points of the laser semiconductor array units;
• a beam synthesizing device arranged to synthesize the coupled beams to obtain m×n number of beams;
• and
• an optical deflector arranged to deflect the m×n number of beams at substantially the same time such that the deflected beams are impinged on a scanning surface,
• wherein the light emitting points of the semiconductor laser array units are inclined in a direction that coincides with the sub-scanning direction.