Patent attributes
An LED bar lighting with uniform illumination includes at least two LED chips, and a bar lens. Each of at least two LED chips includes an optical axis. The bar lens includes an in-light surface profile line and an out-light surface profile line in a cross section perpendicular to the axial direction of the bar lens. The in-light surface profile line includes a first arc and tow second arcs arranged two sides of the first arc. The first arc is tangent to the second arc and the radius of the first arc is smaller than that of the second arc. The radius of the out-light surface profile line is gradually reduced toward two sides thereof from an intersection of the out-light surface profile line and the optical axis. The radius of the out-light surface profile line at the intersection of the out-light profile line and the optical axis is infinite, and the refraction angle at both end points of the out-light surface profile line is 0 degree.