LED module

1. An LED module, comprising:

a printed circuit board, PCB, with a plurality of LEDs mounted thereon; and

first and second optical cover plates each comprising an optically transmissive portion and coupled to the PCB so as to cover a respective subset of the plurality of LEDs,

wherein the first and second optical cover plates have complementary geometries so that they are self-aligning in two axes, each of the first and second optical cover plates further comprises a respective sealing groove surrounding the respective subset of the plurality of LEDs;

wherein each of the respective sealing grooves has a U-shaped cross section, the U-shaped cross section being formed in the respective cover plate by a base that extends from an edge of the cover plate and is essentially parallel to the cover plate, and two standing walls each connected to the base;

and wherein the complementary geometries bridge the respective sealing grooves of the first and second optical cover plates to form one integral sealing groove.

2. The LED module of claim 1 , wherein adhesive sealant is provided in each of the sealing grooves to sealably adhere the optical cover plate to the PCB.

3. The LED module of claim 1 , wherein the first and second optical cover plates comprise interlocking geometries adapted to maintain the first and second optical cover plates in a predetermined arrangement relative to each other.

4. The LED module of claim 3 , wherein the interlocking geometry comprises a projection formed to extend from the first optical cover plate and adapted to engage with a channel or aperture formed in the second optical cover plate.

5. The LED module of claim 1 , wherein the optically transmissive portion of at least one of the first and second optical cover plates comprises an optical enhancement material.

6. A method of covering a printed circuit board, PCB, having a plurality of LEDs mounted thereon, the method comprising:

coupling each of a first and second optical cover plate to the PCB so as to cover a respective subset of the plurality of LEDs, wherein each cover plate comprises an optically transmissive portion and the first and second cover plate have complementary geometries so they are self-aligning in two axes;

providing each of the first and second optical covers plates with a respective sealing groove arranged to surround the respective covered subset of the covered LEDs;

wherein each of the respective sealing grooves has a U-shaped cross section, the U-shaped cross section being formed in the respective cover plate by a base that extends from an edge of the cover plate and is essentially parallel to the cover plate, and two standing walls each connected to the base; and,

forming the respective sealing grooves of the adjacent first and second optical cover plates by the complementary geometries into one, integral sealing groove.

7. The method of claim 6 , further comprising: providing adhesive sealant in each of the sealing groves, the adhesive sealant being adapted to sealably adhere the optical cover plate to the PCB.

8. The method of claim 6 , wherein the first and second optical cover plates comprise interlocking geometries adapted to maintain the first and second optical cover plates in a predetermined arrangement relative to each other.

9. The method of claim 8 , wherein the interlocking geometry comprises a projection formed to extend from the first optical cover plate and adapted to engage with a channel or aperture formed in the second optical cover plate.

10. The method of claim 6 , wherein the optically transmissive portion of at least one of the first and second optical cover plates comprises an optical enhancement material.