Patent ID: 8827503

Claim:
An optical lens for lighting fixture, comprising a body, said body comprising a bottom surface at a bottom side thereof, a light-exit surface at a top side thereof, an elongated groove being concave in the direction towards the inner side of the body formed in said bottom surface for accommodating a light source, a first axis extending between two opposing ends of said bottom surface, a second axis extending between two opposing sides of said bottom surface across said first axis in a perpendicular manner, said first axis being longer than said second axis, said elongated groove comprising a major axis disposed in parallel to said second axis and a first end surface and a second end surface respectively disposed at two opposite ends thereof, a light incident surface being part of a wall of said elongated groove and connected with said first and second end surfaces, said first end surface and said second end surface being respectively intersected with said second axis, a first intersection line formed between said first end surface and said bottom surface, a second intersection line formed between said second end surface and said bottom surface, said light incident surface being formed of at least one curved surface portion, said at least one curved surface portion being connected to said bottom surface at two opposite sides of said elongated groove to form a first line segment at one side of said elongated groove and a second line segment at an opposite side of said elongated groove, said first line segment and said second line segment being disposed at two opposite sides relative to the major axis of said elongated groove in a symmetric manner relative to said second axis, said at least one curved surface portion being disposed at two opposite side relative to said second axis in an symmetric manner, a first virtual line being a straight line connected between two opposite ends of said first line segment, a first distance defined as the shortest distance between two opposite ends of said first intersection line, the shortest distance between any point at said first line segment and said virtual line being defined to be SAGi that satisfies the equation: 0≦|SAGi/first distance|×100≦2.8.