Laser diode

A laser diode comprising:

• a substrate;
• a plurality of strip-shaped laser structures arranged in parallel with respect to each other, each including a lower cladding layer, an active layer, and an upper cladding layer in this order on the substrate;
• grooves between the strip-shaped laser structures, the grooves extending into the substrate;
• a plurality of strip-shaped upper electrodes respectively formed on top faces of the laser structures, each electrode being electrically connected to the respective upper cladding layer;
• a plurality of wiring layers extending in a direction across the plurality of strip-shaped laser structures, each wiring layer electrically connected to a respective upper electrode;
• first and second pad electrode regions between which are located the strip-shaped laser structures and the grooves, each pad electrode region having a groove adjacent thereto;
• and
• a plurality of pad electrodes formed in the pad electrode regions, each pad electrode electrically connected to a respective upper electrode via a respective wiring layer such that the wiring layers alternately extend from a respective pad electrode in one pad electrode region to the other pad electrode region where it is not connected to a pad electrode,
• wherein,
• the grooves are effective to eliminate electrical crosstalk between adjacent laser structures,
• each wiring layer has an end in a region different from a region where the respective wiring layer is connected with its respective upper electrode, and
• the end of each wiring layer extends across the groove adjacent the other pad electrode region.