Patent ID: 7212353

Claim:
An optical element comprising a transparent member having: a first refracting surface; a second refracting surface; and a plurality of reflecting surfaces, wherein the transparent member is capable of causing light, which enters the transparent member from the first refracting surface, to be reflected at least three times by the plurality of reflecting surfaces and guided to the second refracting surface, wherein an optical path from the first refracting surface leading to the second refracting surface crosses itself inside the transparent member when seen from a direction that is substantially perpendicular to both incident light on the first refracting surface and light exiting from the second refracting surface, wherein the transparent member comprises projecting portions having no optical action provided on both sides of the transparent member, and wherein each one of the plurality of reflecting surfaces is located in one of a first region or a second region and reflects the incident light to another surface located in the other of the first region or the second region, the first region and the second region being regions on one and the other sides, respectively, of a first plane passing through the projecting portions provided on both sides of the transparent member which is taken as a boundary.