The one or more LED filaments (110) are arranged to form an inner space. At least one of the one or more LED filaments (110) is arranged as a LiFi transmitter. The LiFi device (100) further comprises a light sensor (120) arranged within the inner space. The light sensor (120) is arranged as a LiFi receiver. The LiFi device further comprises an envelope arranged to envelope the one or more LED filaments (110) and the light sensor (120). The one or more LED filaments (110) are further arranged such that the LED filament light is directed towards the envelope.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics.

An LED light bulb includes a bulb shell, a bulb base, two conductive supports, a stem, and an LED filament. The bulb base is connected with the bulb shell. The two conductive supports are disposed in the bulb shell. The stem extends from the bulb base to inside of the bulb shell. The LED filament includes a plurality of LED chips and two conductive electrodes. The LED chips are arranged in an array along an elongated direction of the LED filament. The two conductive electrodes are respectively disposed at two ends of the LED filament and connected to the LED chips. The two conductive electrodes are respectively connected to the two conductive supports. The LED filament is curled to satisfy symmetry characteristics.

The present disclosure relates to a light-emitting diode (LED) filament (100) comprising a carrier (120) having a first side on which a plurality of LEDs is arranged. The plurality of LEDs comprises a LED of a first type (111) arranged to emit light having a first peak wavelength in the range 400-500 nm, a LED of a second type (112) arranged to emit light having a second peak wavelength in the range 500-570 nm, and a LED of a third type (113) arranged to emit light having a third peak wavelength in the range 590-680 nm. An encapsulant (130) encapsulates at least the LED of the first type, and at least partly the LEDs of the second type and the third type. The encapsulant (130) comprises a wavelength converting material having a higher absorption coefficient for the first peak wavelength than for the second peak wavelength and the third peak wavelength. The wavelength converting material has an emission band extending at least from 500 to 650 nm.

The present disclosure relates to a light-emitting diode (LED) filament (100) comprising a carrier (120) having a first side on which a plurality of LEDs is arranged. The plurality of LEDs comprises a LED of a first type (111) arranged to emit light having a first peak wavelength in the range 400-500 nm, a LED of a second type (112) arranged to emit light having a second peak wavelength in the range 500-570 nm, and a LED of a third type (113) arranged to emit light having a third peak wavelength in the range 590-680 nm. An encapsulant (130) encapsulates at least the LED of the first type, and at least partly the LEDs of the second type and the third type. The encapsulant (130) comprises a wavelength converting material having a higher absorption coefficient for the first peak wavelength than for the second peak wavelength and the third peak wavelength. The wavelength converting material has an emission band extending at least from 500 to 650 nm.

There is provided a light emitting diode, LED, filament lamp (100) which provides LED filament lamp light (100′). The LED filament comprises a first linear array of LEDs (101) and a second linear array of LEDs (106), and a carrier (103). The first linear array of LEDs (101) are arranged on a first surface (102) of the carrier (103) and includes only first LEDs (104) which are configured to emit first white light (105). The second linear array of LEDs (106) are arranged on a second surface (107) of the carrier (103), opposite to said first surface (102), and includes only second LEDs (108) which are configured to emit color controllable light (109). The LED filament light (100′) comprises the first white light (105) and/or the color controllable light (109).

There is provided a light emitting diode, LED, filament lamp (100) which provides LED filament lamp light (100′). The LED filament comprises a first linear array of LEDs (101) and a second linear array of LEDs (106), and a carrier (103). The first linear array of LEDs (101) are arranged on a first surface (102) of the carrier (103) and includes only first LEDs (104) which are configured to emit first white light (105). The second linear array of LEDs (106) are arranged on a second surface (107) of the carrier (103), opposite to said first surface (102), and includes only second LEDs (108) which are configured to emit color controllable light (109). The LED filament light (100′) comprises the first white light (105) and/or the color controllable light (109).

It is an object of the invention to provide an improved LED filament lamp (10), the LED filament lamp (10) comprising: a transparent envelope (11) provided with a transparent optical structure (12); at least one LED filament (14) enclosed by the transparent envelope (11); wherein the transparent optical structure (12) comprises a plurality of individually spaced prismatic grooves (17) and/or ridges that are at least partly aligned along a projection of the at least one LED filament (14) on the transparent envelope (11); wherein each prismatic groove (17) and/or ridge of the plurality of individually spaced prismatic grooves (17) and/or ridges comprises a refractive facet (171) oriented at a wedge angle (172) between 5 and 50 degrees with a tangent of the envelope (11) at the location of the respective prismatic groove (17) and/or ridge.

It is an object of the invention to provide an improved LED filament lamp (10), the LED filament lamp (10) comprising: a transparent envelope (11) provided with a transparent optical structure (12); at least one LED filament (14) enclosed by the transparent envelope (11); wherein the transparent optical structure (12) comprises a plurality of individually spaced prismatic grooves (17) and/or ridges that are at least partly aligned along a projection of the at least one LED filament (14) on the transparent envelope (11); wherein each prismatic groove (17) and/or ridge of the plurality of individually spaced prismatic grooves (17) and/or ridges comprises a refractive facet (171) oriented at a wedge angle (172) between 5 and 50 degrees with a tangent of the envelope (11) at the location of the respective prismatic groove (17) and/or ridge.

The present invention relates to an LED filament lamp (10) comprising a two-dimensional flexible printed circuit board (100), PCB, having a first and a second opposing connection end portions (110, 120). The two-dimensional flexible PCB (100) comprises a plurality of filaments lines (130a-d) extending from the first connection end portion (110) to the second connection end portion (120), wherein each filament line (130a) comprises an array of LEDs (130.sub.a1-130.sub.aN). The two-dimensional flexible PCB (100) is arranged in a cylinder shape by connecting the first and the second opposing connection end portions (110, 120) such that each (130a) of the plurality of filament lines (130a-d) is connected to another (130b) one of the plurality of filament lines (130a-d) thereby a spiral LED filament (150) is formed by the plurality of filament lines (130a-d).