Patent ID: 9599292
Date: 2017-03-21
CPC Classifications: F21K,F21Y,H01L

Claim:
1. A light emitting module comprising: a light exit window; a base comprising a light reflective surface facing the light exit window, the light reflective surface having a base reflection coefficient (Rbase) being defined by a ratio between the amount of light that is reflected by the light reflective surface of the base and the amount of light that impinges on the light reflective surface of the base; at least one solid state light emitter disposed on the base arranged for emitting light of a first color, the at least one solid state light emitter having a top surface and having a solid state light emitter reflection coefficient (R_SSL) being defined by a ratio between the amount of light that is reflected by the top surface and the amount of light that impinges on the top surface, wherein the top surface of the at least one solid state light emitter faces towards the light exit window, a wall interposed between the base and the light exit window, the base, the wall and the light exit window enclosing a cavity, the wall comprising a reflective material forming a light reflective wall surface facing towards the cavity, the light reflective wall surface having a wall reflection coefficient (Rwall) being defined by a ratio between the amount of light that is reflected by the light reflective wall surface and the amount of light that impinges on the light reflective wall surface, wherein an effective reflective coefficient (Reff) is defined as a weighted average of the base reflection coefficient (Rbase) and the wall reflection coefficient (Rwall), wherein a solid state light emitter area ratio (ρ a partially diffusive reflective layer, comprising a luminescent material for converting at least a part of the light of the first color into light of a second color, the light exit window comprising at least a part of the partially diffusive reflective layer, wherein a gap with a distance h is present between the top surface of the at least one solid state light emitter and the partially diffusive reflective layer for which 0.3·d wherein the value of the effective reflection coefficient (Reff) is larger than 70% and larger than the solid state light emitter reflection coefficient (R_SSL) and wherein the wall reflection coefficient (Rwall) is smaller than 95%.