Patent ID: 8217411

Claim:
A light emitting device including a first area and a second area adjacent to the first area in a plan view, the light emitting device comprising: a substrate formed in the first and second areas; a first cladding layer formed above the substrate in the first area; an active layer formed above the first cladding layer, the active layer having first and second side surfaces opposite to each other; a gain area formed in at least part of the active layer, the gain area having first and second end surfaces opposite to each other, the first end surface being provided at least along the second side surface; a second cladding layer formed above the active layer; a guide layer formed above the substrate in the second area; and a core layer formed above the guide layer, the core layer having third and fourth side surfaces opposite to each other, wherein the third side surface is adjacent to the first end surface, of the gain area, light produced in the gain area passes through the first end surface of the gain area, travels through the core layer to the fourth side surface, and exits through the fourth side surface, and the gain area extending from the first end surface to the second end surface is angled relative to a first normal direction of the first side surface, and the first end surface and the second end surface do not overlap each other in the first normal direction.