A planar collimator has first and second sections each intersecting at a junction between a first axis and a second axis normal to the first axis. Each of the first and second sections have geometries configured to receive light from a source point located on the first axis and collimate the light at respective positive and negative tilting angles relative to the second axis. The first and second sections direct the collimated light to respective first and second sides of a focusing mirror and away from a gap between the first and second sides of the focusing mirror.