A first semiconductor laser element and a second semiconductor laser
element are arranged on an identical block, a first electrode of the
first semiconductor laser element is in direct contact with the block,
and heat radiating effect is high. A second electrode of the second
semiconductor laser element is arranged on an insulating dielectric
layer, and the block and second semiconductor laser element are
electrically insulated. Therefore, irrespective of the material to
compose the block, the first semiconductor laser element and the second
semiconductor laser element can be independently driven. In addition, the
light emitting point distance between the first semiconductor laser
element and second semiconductor laser element is limited only by the
distance between the electrodes of the respective semiconductor lasers
and the positions of light emitting points on the semiconductor laser
chip end face and can, therefore, be made as short as possible.