Patent attributes
An illumination device comprising an optical plate extending over a plurality of LEDs arranged on a PCB main surface of a PCB. In a mounted configuration said PCB and optical plate are mutually connected by fasteners. Each fastener extends with play in a plane parallel to said PCB main surface through a through hole in the optical plate in a direction transverse to said PCB main surface. The through hole has a wide portion extending over a depth D from a first main surface of the optical plate facing away from the PCB towards a second main surface of the optical plate facing towards the PCB, and said through hole is narrowed to a neck portion at said depth D. Furthermore, each fastener rests on a resilient washer seated in the wide portion of said through hole.