Patent ID: 7999990

Claim:
An optical element comprising: a plurality of first beam bodies arranged in a first direction on a first plane and being parallel to each other; and a plurality of second beam bodies, each of the second beam bodies being placed between adjacent ones of the first beam bodies and provided parallel to the first beam bodies, wherein, each of the first beam bodies has side surfaces which face the second beam bodies adjacent thereto and are sloped so that a width of the each of the first beam bodies in the first direction gradually decreases to an upward direction perpendicular to the first plane, each of the second beam bodies has side surfaces which face the first beam bodies adjacent thereto and are sloped so that a width of the each of the second beam bodies in the first direction gradually increases to the upward direction, and as viewed in the first direction, a spacing between one of the first beam bodies and one of the second beam bodies adjacent to the one of the first beam bodies being adjustable.