A light emission device comprising two or more semiconductor light emitting elements flip-chip mounted in a line form on a supporting substrate, each of the semiconductor light emitting elements comprising a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type arranged in order on a transparent substrate, a first electrode arranged on an exposure part of the first semiconductor layer, a second electrode arranged on the second semiconductor layer, and a light emitting layer between the first semiconductor layer and the second semiconductor layer, an end face of the light emitting layer being exposed between the exposure part of the first semiconductor layer and the second semiconductor layer arranged with the second electrode; wherein one of the semiconductor light emitting elements, referred to as said semiconductor light emitting element, has in a plan view a rectangular shape including a first side having a length L 1, a second side having a length L 2, a third side which is an opposing side of the first side, and a fourth side which is an opposing side of the second side; the second electrode surrounds the exposure part; the first side of the light emitting element directly faces the exposure part of the first semiconductor layer and the third side of the light emitting element when seen from the first side in the direction of the third side, wherein the region of the second electrode which is, in plan view, between the first side and the portions of the third side and of the exposure part which are directly faced by the first side, has a surface area R 1; the second side of the light emitting element directly faces the exposure part of the first semiconductor layer and the fourth side of the light emitting element when seen from the second side in the direction of the fourth side,wherein the region of the second electrode which is, in plan view, between the second side and the portions of the fourth side and of the exposure part which are directly faced by the second side, has a surface area R 2; a ratio R 1 /L 1 of R 1 and L 1 is smaller than a ratio R 2 /L 2 of R 2 and L 2 whereby light exited from an element end face on the first side is stronger than light exited from an element end face on the second side; the light emission device comprises another semiconductor light emitting element having the same construction as said semiconductor light emitting element; and said semiconductor light emitting element and said another semiconductor light emitting element are arranged so that the first side of said semiconductor light emitting element and the first side of said another semiconductor light emitting element face each other substantially in parallel and so that the second side of said semiconductor light emitting element does not face an adjacent semiconductor light emitting element. a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type arranged in order on a transparent substrate, a first electrode arranged on an exposure part of the first semiconductor layer, a second electrode arranged on the second semiconductor layer, and a light emitting layer between the first semiconductor layer and the second semiconductor layer, an end face of the light emitting layer being exposed between the exposure part of the first semiconductor layer and the second semiconductor layer arranged with the second electrode; wherein