| CPC F21K 9/232 (2016.08) [F21K 9/68 (2016.08); F21Y 2103/10 (2016.08); F21Y 2113/13 (2016.08); F21Y 2115/10 (2016.08)] | 12 Claims |
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1. A color tunable and/or color temperature tunable light emitting diode, LED, filament, said LED filament comprising:
an elongated carrier, said elongated carrier comprising a first major surface and a second major surface arranged opposite to said first major surface,
a plurality of LEDs arranged in at least one linear array on said first surface of said elongated carrier, wherein the plurality of LEDs includes LEDs of different colors and/or different color temperatures,
a first elongated transparent or substantially transparent layer covering the plurality of LEDs on the first major surface and also at least partly covering said first major surface,
a first elongated light scattering layer, arranged to at least partially cover said first transparent or substantially transparent layer, and
wherein the first elongated light scattering layer has an angular gradient in reflectance such that the reflectance is highest in a portion (R8) of the first elongated light scattering layer being substantially parallel to said first major surface of the elongated carrier.
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