Patent ID: 9618190
Date: 2017-04-11
CPC Classifications: F21K,F21V,F21Y,H01L

Claim:
1. An LED module comprising a plurality of light-emitting diodes, wherein the plural light-emitting diodes are disposed only on a lateral surface of a right cone, a right pyramid, a truncated right cone, or a truncated right pyramid, the lateral surface has an inclination angle of 55° or more and 82° or less with respect to a bottom surface, the plural light-emitting diodes have light-emitting surfaces substantially parallel to the lateral surface, and angles formed between projection lines of lines normal to light-emitting surfaces of adjacent light-emitting diodes or adjacent ones of grouped light-emitting diodes, the projection lines being drawn on the bottom surface, are all equal to each other and are 72° or less, further comprising a metal base material having, in a central portion, a protrusion having a shape of the right cone, the right pyramid, the truncated right cone, or the truncated right pyramid, wherein the plural light-emitting diodes are mounted on a flexible printed circuit board, and the flexible printed circuit board is at least disposed so as to conform to the protrusion of the metal base material; wherein the flexible printed circuit board includes a base film, a conductive pattern formed on a front surface side of the base film and including at least one land part and a wiring part connected to the land part, and a coverlay formed on a front surface of the conductive pattern and having an opening formed at a position corresponding to the at least one land part, a back surface of the flexible printed circuit board has a recess extending to a back surface of the conductive pattern, the recess corresponding to at least a portion of a projection region of the at least one land part on which each light-emitting diode is mounted, the flexible printed circuit board further includes thermally conductive adhesive layers filling the recess, and the thermally conductive adhesive layers are a first thermally conductive adhesive layer formed on the back surface of the conductive pattern and used to fill the front surface portion of the recess, and a second thermally conductive adhesive layer formed on the back surface of the first thermally conductive adhesive layer and used to fill the back surface portion of the recess, wherein the second thermally conductive adhesive layer has a lower thermal conductivity than the first thermally conductive adhesive layer.