| 摘要 |
The invention relates to an illumination system (10) comprising a light emitting device (20) and a beam shaping element (30) for generating an angular distribution (φ) of the light emitted from the illumination system. The beam shaping element is configured for recycling at least a part of the light emitted from a light emitting surface (26) of the light emitting device via reflection back towards the light emitting surface. The illumination system further comprises a diffuser (40, 42) arranged substantially parallel to the light emitting surface for diffusing at least part of the recycled light. The diffuser is constituted of a translucent diffuser (40) and/or a diffusely reflective electrode layer (42) of the light emitting device. Limiting the angular distribution by recycling light, using the beam shaping element for recycling light via reflection, reduces glare when the illumination system is used in general lighting applications. The diffuser avoids that the recycled light is confined between the beam shaping element and the light emitting surface of the light emitting element. The recycling is preferably done via total internal reflection at the beam shaping element. The presence of the diffuser improves the efficiency of the illumination system.
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