Abstract: The invention provides a lamp (1) comprising (i) a solid state light source (10) and a first envelope (100) at least partially enclosing the light source (10), thereby forming a first cavity (150) hosting said solid state light source (10), wherein at least part of the first envelope (100) is transmissive for visible light (11) generated by the solid state light source (10); and (ii) a second envelope (200) at least partially enclosing the first envelope (100), wherein the first envelope (100) and the second envelope (200) provide a second cavity (250) at least partially enclosing the light source (10), wherein at least part of the second envelope (200) is transmissive for visible light (11) generated by the light source (10) and transmitted through the first envelope (100) into the second cavity (250), wherein the second cavity (250) is configured as a heat pipe (251).

Abstract: The invention provides alighting unit (100) comprising a light source (10) and a light conversion layer (20). The light source (10) comprises a light emitting diode (LED) (110) and a first luminescent material layer (120) in physical contact with a light emitting surface (115) of the LED (110). The first luminescent material layer (120) comprises a first luminescent material (130), configured to convert at least part of LED light (111) into light (131) having a red component. The light source (10) is configured to generate light (11) having a blue component and having the red component of the light (131). The light conversion layer (20), configured at a non-zero distance (d) from the light source (10), comprises a second luminescent material (30) configured to convert at least part of the light (11) into light (31). The lighting unit (100) is configured to provide white lighting unit light (111).

Abstract: The invention provides alighting unit (100) comprising a light source (10) and a light conversion layer (20). The light source (10) comprises a light emitting diode (LED) (110) and a first luminescent material layer (120) in physical contact with a light emitting surface (115) of the LED (110). The first luminescent material layer (120) comprises a first luminescent material (130), configured to convert at least part of LED light (111) into light (131) having a red component. The light source (10) is configured to generate light (11) having a blue component and having the red component of the light (131). The light conversion layer (20), configured at a non-zero distance (d) from the light source (10), comprises a second luminescent material (30) configured to convert at least part of the light (11) into light (31). The lighting unit (100) is configured to provide white lighting unit light (111).