Patent ID: 8632224
Filing Date: 2014-01-21
Classification: G02B,G03B,H01L,H04N

Abstract:
1. A light emitting device comprising: a first light emission element which has a first emission surface for emitting a first emission light, an a second emission surface for emitting a second emission light traveling in a direction opposite to the direction of the first emission light, and a first gain area that generates the first emission light and the second emission light and that is connected between the first emission surface and the second emission surface; a second light emission element which has a third emission surface for emitting a third emission light traveling in the same direction as the direction of the first emission light, a fourth emission surface for emitting a fourth emission light traveling in the direction opposite to the direction of the third emission light, and a second gain area that generates the third emission light and the fourth emission light and that is connected between the third emission surface and the fourth emission surface; a first reflection surface which reflects the first emission light emitted from the first light emission element; a second reflection surface which reflects the second emission light emitted from the first light emission element; a third reflection surface which reflects the third emission light emitted from the second light emission element; and a fourth reflection surface which reflects the fourth emission light emitted from the second light emission element; wherein the first light emission element and the second light emission element are laminated in a first direction, the first emission surface and the third emission surface are located within a first plane, the second emission surface and the fourth emission surface are located within a second plane, the first emission surface and the third emission surface are disposed in such positions as to be shifted from each other in the first direction in the first plane, the second emission surface and the fourth emission surface are disposed in such positions as to be shifted from each other in the first direction in the second plane, the first gain area and the second gain area do not overlap with each other as viewed in the first direction the first reflection surface and the third reflection surface are disposed in such positions that the optical path length of the first emission light between the first emission surface and the first reflection surface becomes equal to the optical path length of the third emission light between the third emission surface and the third reflection surface, the second reflection surface and the fourth reflection surface are disposed in such positions that the optical path length of the second emission light between the second emission surface and the second reflection surface becomes equal to the optical path length of the fourth emission light between the fourth emission surface and the fourth reflection surface, and a traveling direction of the first emission light reflected by the first reflection surface, a traveling direction of the second emission light reflected by the second reflection surface, a traveling direction of the third emission light reflected by the third reflection surface, and a traveling direction of the fourth emission light reflected by the fourth reflection surface are equalized.