LED module i.e. chip-on-board module, for use in e.g. spotlight, has phosphor particles whose concentration decreases with gradient in region formed adjacent to another region, and phosphor layer applied on radiation surface of chip

摘要

The module (1) has a LED chip (2) arranged on a carrier (3) e.g. aluminum plate and printed circuit board, and a phosphor layer (8) applied on a light radiation surface of the chip. Phosphor particles (6) in a matrix (4) are retained in the phosphor layer. Concentration of the phosphor particles is constant in a region such that color conversion particles are densely packed in the region, where the region surrounds the chip. The concentration of the phosphor particles decreases with a gradient in another region that is formed adjacent to the former region. The matrix is made of polymer.