Patent ID: 8552440
Filing Date: 2013-10-08
Classification: H01L

Abstract:
1. A lighting device comprising: plural stages of light-emitting element units; a first wiring in contact with a first-stage light-emitting element unit of the plural stages of light-emitting element units; and a second wiring in contact with a last-stage light-emitting element unit of the plural stages of light-emitting element units, wherein the first-stage light-emitting element unit includes at least a first light-emitting element and a second light-emitting element which are connected in parallel, wherein a light-emitting element unit adjacent to the first-stage light-emitting element unit includes at least a third light-emitting element and a fourth light-emitting element which are connected in parallel, wherein the first light-emitting element, the second light-emitting element, the third light-emitting element, and the fourth light-emitting element each include a first electrode layer with a light-transmitting property, an organic compound-containing layer which is in contact with the first electrode layer, a second electrode layer with reflectivity which is in contact with the organic compound-containing layer, and an auxiliary wiring which is in contact with the first electrode layer and has a narrower width than the first wiring and the second wiring, wherein the second electrode layer of the first light-emitting element and the auxiliary wiring of the third light-emitting element are connected to each other, so that the first light-emitting element and the third light-emitting element are connected in series, wherein the second electrode layer of the second light-emitting element and the auxiliary wiring of the fourth light-emitting element are connected to each other, so that the second light-emitting element and the fourth light-emitting element are connected in series, wherein the auxiliary wiring of each of the light-emitting elements in the first-stage light-emitting element unit is in contact with the first wiring, and wherein the second electrode layer of each of the light-emitting elements in the last-stage light-emitting element unit is in contact with the second wiring.