Patent ID: 7457509

Claim:
A light-guiding device having a coupling-in surface for coupling-in light radiation substantially in a first main direction perpendicular to said coupling-in surface, and having a coupling-out surface for coupling-out light radiation substantially in a second main direction perpendicular to said coupling-out surface, wherein the coupling-out surface has dimensions other than those of the coupling-in surface, characterized in that the device comprises a number of light-guiding members, each light-guiding member being configured in the form of a substantially planar plate and having (i) a substantial rectangular lateral coupling-in surface, (ii) two lateral outer surfaces bordering the rectangular lateral coupling-in surface configured to narrow an angular distribution of light radiation around the first main direction, and (iii) a substantially rectangular lateral coupling-out surface, wherein a number of the light-guiding members are stacked together so as to create the coupling-in surface formed by said lateral coupling-in surfaces abutting each other at their long sides, and wherein the coupling-out surface is created by said lateral coupling-out surfaces abutting each other at their short sides.