Abstract: The invention relates to a lighting device (1) comprising an envelope (2), a base (3), a solid-state light source (4) and optical means (5) provided with a light-outcoupling surface, the solid-state light source (4) being optically coupled to said optical means (5). The use of a spirally wound optical fiber as optical means (5) and a transparent envelope (2) shaped as a conventional light bulb provides a lighting device (1) which is a good look -alike of the conventional incandescent lamp, such as, for instance, the carbon filament lamp. The long lifetime and high efficiency of LEDs as a solid-state light source (4) will make this lighting device (1) a very attractive alternative for the conventional incandescent lamp. The lighting device (1) according to the present invention has the further advantage that a large gamut of colors can be chosen and adjusted by using, for instance, red green and blue LEDs in said lighting device (1).

Abstract: The invention relates to a lighting device (1) comprising an envelope (2), a base (3), a solid-state light source (4) and optical means (5) provided with a light-outcoupling surface, the solid-state light source (4) being optically coupled to said optical means (5). The use of a spirally wound optical fiber as optical means (5) and a transparant envelope (2) shaped as a conventional light bulb provides a lighting device (1) which is a good look-alike of the conventional incandescent lamp, such as, for instance, the carbon filament lamp. The long lifetime and high efficiency of LEDs as a solid-state light source (4) will make this lighting device (1) a very attractive alternative for the conventional incandescent lamp. The lighting device (1) according to the present invention has the further advantage that a large gamut of colors can be chosen and adjusted by using, for instance, red green and blue LEDs in said lighting device (1).

Abstract: The invention relates to a lighting device (1) comprising an envelope (2), a base (3), a solid-state light source (4) and optical means (5) provided with a light-outcoupling surface, the solid-state light source (4) being optically coupled to said optical means (5). The use of a spirally wound optical fiber as optical means (5) and a transparant envelope (2) shaped as a conventional light bulb provides a lighting device (1) which is a good look-alike of the conventional incandescent lamp, such as, for instance, the carbon filament lamp. The long life-time and high efficiency of LEDs as a solid-state light source (4) will make this lighting device (1) a very attractive alternative for the conventional incandescent lamp. The lighting device (1) according to the present invention has the further advantage that a large gamut of colors can be chosen and adjusted by using, for instance, red green and blue LEDs in said lighting device (1).

Abstract: The invention provides a filament lamp (1) having a filament (20), wherein the filament comprises tantalum carbide. The filament lamp comprises a lamp base part filament construction (15) which comprises a lamp base part (10) with a base part (11) top and a coil (21) comprising tantalum carbide connected to lead-in connections (23), the lead-in connections extending through the base part. The filament lamp further comprises a lamp bulb (40) connected to the base part top (11), thereby providing a filament enclosure (44), which filament enclosure comprises a gas filling (45). The invention further provides a process for making such a lamp.

Abstract: The invention describes a method of treating a halogen lamp (1) comprising a filament (4) supported by legs (3, 3?) in a vitreous bulb (2) enclosing a halogenated hydrocarbon fill gas (G), which method comprises applying heat and/or radiation to the lamp (1)—prior to initial operation of the lamp (1)—from a source (S1, S2) external to the lamp (1), so that the halogenated hydrocarbon fill gas (G) is cracked and carbon is deposited essentially at a specific region (R1, R2) of the lamp (1), whereby the specific region (R1, R2) of the lamp (1) is a region in the lamp (1) other than the legs (3, 3?) of the filament (4) of the lamp (1).

Abstract: The invention relates to a lamp-reflector unit (3) provided with a first (15) and a second light source (17) axially disposed on a lamp axis (1), and a reflector (7) with a reflecting part (13). A modification of the reflecting part of the reflector to a shape somewhere in between a parabolic shape and a shape of a straight cone achieves that light of a narrow beam, i.e. a beam with a beam angle less than 15°, is obtained from the first light source, while the light beam as obtained from the second light source does not show any “optical hole” in its center.

Abstract: The electric lamp comprises a lamp vessel (11) which transmits visible light and which accommodates a light source (12). The electric lamp comprises a light-absorbing medium (16). The lamp vessel (11) is covered with an optical interference film (15) which comprises layers composed of a first layer of silica and a second layer of a material having a relatively high refractive index which alternate with each other. According to the invention, light from the light source (12) travels through the light-absorbing medium (16) before reaching the interference film (15). Preferably, the light-absorbing layer (16) is disposed between the lamp vessel (11) and the interference film (15). Alternatively, the light-absorbing layer is contained in a wall of the lamp vessel. Preferably, the interference film (15) reflects substantially in the same wavelength range as that wherein the light-absorbing medium (16) absorbs, preferably in the range from 570 to 620 nm.