Patent ID: 7699502

Claim:
A lighting device comprising: a light source that is an array comprising a plurality of light-emitting diode elements arranged in a row; and an optical member having a substantially rectangular parallelepiped shape elongated in a longitudinal direction of the array, the optical member comprising: an entrance bottom surface opposed to the light source and configured to receive light from the light source; an exit top surface opposite to the entrance bottom surface and configured to emit the light outside the optical member; an outer peripheral side surface disposed between the entrance bottom surface and the exit top surface; and a plurality of recessed surfaces formed on the outer peripheral side surface and extending in the longitudinal direction of the array in which the light-emitting elements are arranged, the plurality of recessed surfaces configured to totally reflect the entered light inwardly, the plurality of recessed surfaces comprising surfaces of a plurality of grooves each having a V-shaped sectional configuration, the grooves being formed on a pair of opposite side surfaces of the outer peripheral side surface and each extending in the longitudinal direction of the array.