Abstract: The present invention includes: a front-side positive trace (2P) disposed on a flexible substrate (5); a positive external connection line (12P) connected to the front-side positive trace (2P) to supply electric power; and LED chips (4) provided to the flexible substrate (5) and connected to the front-side positive trace (2P), wherein an electric resistance between the positive external connection line (12P) and one of the LED chips (4) which is farthest from the positive external connection line (12P) is less than an internal resistance of the one of the LED chips (4).