Fluorescent tube

• US 20020047516A1
• Filed: 10/23/2001
• Published: 04/25/2002
• Est. Priority Date: 10/24/2000
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Takano, Shinji, Iwasa, Tadanobu
• Granted Patent: US 6,583,550 B2
• Time in Patent Office: Days
• US Class Current: 313/512
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21V 9/02 for simulating daylight F21V9/04, F21V9/06 take precedence
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G09F 13/20 with luminescent surfaces or parts luminescent compositions C09K11/00; light sources using luminescence F21K2/00
• CPC Class Codes: H01J 61/32 Special longitudinal shape, e.g. for advertising purposes H01J61/305 takes precedence
• CPC Class Codes: H01J 61/56 One or more circuit elements structurally associated with the lamp
• CPC Class Codes: H01J 61/72 having a main light-emitting filling of easily vaporisable metal vapour, e.g. mercury

Abstract

A fluorescent tube is constituted by a fluorescent tubular body having a transparent glass tube coated with a fluorescent layer containing a fluorescent material on its inner surface, and an ultraviolet LED substrate inserted in the fluorescent tubular body and having an equal length to the fluorescent tubular body. The ultraviolet LED substrate has twenty-four ultraviolet light emitting devices each having a long life, and the left end of the ultraviolet LED substrate is connected with lead wires through which electric power is supplied. Accordingly, when ultraviolet rays are emitted from the twenty-four ultraviolet light emitting devices, the fluorescent layer emits light in its own fluorescent color, the fluorescent tubular body as a whole emits light and the surroundings are illuminated with the light. Hence, the fluorescent tube can be used for illumination. Alternatively, the fluorescent tubular body may be formed by a transparent silicone rubber which can be bent into any desired shape.

Claims

1. A fluorescent tube comprising:

a fluorescent tubular body containing a fluorescent material emitting light in response to irradiation with ultraviolet rays; and

a light emitting diode substrate inserted in said fluorescent tubular body, said light emitting diode substrate including a substrate and one or more ultraviolet light emitting devices disposed on said substrate.

2. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises:

a glass tube; and

a fluorescent layer being applied on one of an inner surface and an outer surface of said glass tube, and containing said fluorescent material.

3. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises:

a transparent resin tube; and

a fluorescent layer being applied on one of an inner surface and an outer surface of said transparent resin tube, and containing said fluorescent material.

4. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises a transparent resin containing said fluorescent material, said transparent resin is extrusion-molded into a pipe shape.

5. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises:

a first resin tube comprising a transparent or semi-transparent deformable synthetic resin; and

a second resin tube comprising a transparent or semi-transparent deformable synthetic resin containing said fluorescent material, said second resin tube being disposed on one of an inner surface and an outer surface of said first resin tube.

6. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises a transparent or semi-transparent deformable synthetic resin containing said fluorescent material dispersed in a whole of said deformable synthetic resin.

7. A fluorescent tube according to claim 1, wherein said fluorescent tubular body comprises:

a resin tube comprising a transparent or semi-transparent deformable synthetic resin; and

a fluorescent layer being applied on one of an inner surface and an outer surface of said resin tube, and containing said fluorescent material.

8. A fluorescent tube according to claim 5, wherein said transparent or semi-transparent deformable synthetic resin is silicone rubber.

9. A fluorescent tube according to claim 6, wherein said transparent or semi-transparent deformable synthetic resin is silicone rubber.

10. A fluorescent tube according to claim 7, wherein said transparent or semi-transparent deformable synthetic resin is silicone rubber.

11. An fluorescent tube according to claim 1, wherein said fluorescent material comprises a red fluorescent material emitting light in red in response to irradiation with ultraviolet rays, a green fluorescent material emitting light in green in response to irradiation with ultraviolet rays, an d a blue fluorescent material emitting light in blue in response to irradiation with ultraviolet rays.

12. A fluorescent tube according to claim 1, wherein said fluorescent material comprises lanthanum sulfide activated with trivalent europium and trivalent samarium, which is substantially expressed by a general formula (La₁₋

x−

yEu_xSm_y)₂O₂S , wherein x and y designate numbers, respectively, satisfying 0.01≦

x≦

0.15 and 0.0001>

y>

0.03.

13. A fluorescent tube according to claim 1, wherein said fluorescent material comprises aluminate activated with bivalent europium and bivalent manganese, which is substantially expressed by a general formula a (M1,Eu,Mn)O.bAl₂O₃, wherein M1 designates at least one element selected from the group of Mg, Ca, Sr, Ba, Zn, Li, Rb, and Cs, and a and b designate numbers, respectively, satisfying a>

0, b>

0, and 0.2≦

a/b≦

1.5.

14. A fluorescent tube according to claim 1, wherein said fluorescent material comprises holophosphate activated with bivalent europium, which is substantially expressed by a general formula (M2,Eu)₁₀(PO₄)₆.Cl₂ (in the formula, M₂ designates at least one element selected from the group of Mg, Ca, Sr, and Ba).

15. A fluorescent tube according to claim 1, wherein said fluorescent material comprises aluminate activated with bivalent europium, which is substantially expressed by a general formula a (M1,Eu)O.bAl₂O₃, wherein M1 designates at least one element selected from the group of Mg, Ca, Sr, Ba, Zn, Li, Rb, and Cs, and a and b designate numbers, respectively, satisfying a>

0, b>

0, and 0.2≦

a/b≦

1.5.

16. A fluorescent tube according to claim 1, wherein each of said ultraviolet light emitting devices has an emission wavelength in a range of from 360 nm to 400 nm.

17. A fluorescent tube according to claim 1, wherein each of said ultraviolet light emitting devices is formed a nitride semiconductor formed of at least one of selected from the group of AlGaInN, AlGaN, GaN, and InGaN.

18. A fluorescent tube according to claim 1, wherein in said light emitting diode substrate, said plurality of ultraviolet light emitting devices are arranged linearly on said substrate.

19. A fluorescent tube according to claim 1, wherein said light emitting diode substrate comprises a plurality of light emitting diode unit substrates which are connected to each other, each of said ultraviolet light emitting diode unit substrates having one or more ultraviolet light emitting devices disposed linearly.

20. A fluorescent tube according to claim 1, wherein said ultraviolet light emitting device is disposed on said light emitting diode substrate while being sealed by transparent resin.

21. A fluorescent tube according to claim 5, wherein said light emitting diode substrate comprises a plurality of light emitting diode unit substrates which are connected to each other through a lead wire flexibly, each of said ultraviolet light emitting diode unit substrates having one or more ultraviolet light emitting devices disposed linearly.

22. A fluorescent tube according to claim 6, wherein said light emitting diode substrate comprises a plurality of light emitting diode unit substrates which are connected to each other through a lead wire flexibly, each of said ultraviolet light emitting diode unit substrates having one or more ultraviolet light emitting devices disposed linearly.

23. A fluorescent tube according to claim 7, wherein said light emitting diode substrate comprises a plurality of light emitting diode unit substrates which are connected to each other through a lead wire flexibly, each of said ultraviolet light emitting diode unit substrates having one or more ultraviolet light emitting devices disposed linearly.

24. A fluorescent tube according to claim 1, further comprising a cover fitted in an end of said fluorescent tubular body, said cover having support means protruding from said cover toward into an inside of said fluorescent tubular body and being coupled with said light emitting diode substrate to thereby support said light emitting diode substrate in a vicinity of an inside center of said fluorescent tubular body.