PROBLEM TO BE SOLVED: To attain a wide light distribution at a road surface in an advancing direction while keeping vertical illumination with a plurality of light-emitting elements having equal irradiation directions or one light-emitting element being applied as a light source.SOLUTION: The present invention relates to a lens 15 arranged at a security light 1 for lighting a road surface 4 for expanding light from an LED 14 acting as a light source of the security light 1 in an advancing direction D1 at the road surface 4. A major light beam Cm directing toward the advancing direction D1 is distributed at a front surface side of the security light 1 under a prescribed angle α in respect to the advancing direction D1.
