ILLUMINATOR AND WIDE LIGHT DISTRIBUTION LENS

摘要

The illuminator is provided with a light source (4) having a light-emitting surface (14), and an optical element (16) which has a shape with a rotational symmetry around an axis orthogonal to the light-emitting surface and traversing the barycenter of the light-emitting surface and which is for transmitting light from the light source. The optical element has a through-hole (18) provided in-line with the axis, an entrance surface (19) facing the light-emitting surface and pierced by the through-hole, an exit surface (20) encircling the axis and extending from the outer circumference of the entrance surface in a direction away from the light source, and a total reflection surface (21) joining the front end of the exit surface and the inner circumference of the entrance surface facing the through-hole so as to define the through-hole. The light from the light source that enters the optical element from the entrance surface is totally reflected in the direction of the exit surface by the total reflection surface.