Linear light source

Patent metadata

Field	Value
Publication number	US-10908342-B2
Application number	US-201816216179-A
Country	US
Kind code	B2
Filing date	Dec 11, 2018
Priority date	Dec 14, 2017
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

A linear light source is provided that includes a light-emitting element and a light guide, which has a core with an end and a longitudinal extension. In the operating state, light from the light emitting element is injected on the end and is guided along the longitudinal extension. The core includes at least one scattering element that changes a propagation direction of the light guided in the core. The light guide having a lateral surface with a light-blocking coating at least partially or in portions thereof. The light-blocking coating being structured so that the light guide has a light-transmissive portion extending along the longitudinal extension and so that the light scattered on the at least one scattering element and striking the light-transmissive portion is able to escape from the light guide, at least partially. The coating having a light transmittance that is lower than a light transmittance of the light-transmissive portion.

First claim

What is claimed is:

1. A linear light source, comprising:
a light guide including a cladding and a transparent core, the transparent core having a first end, a second end, and a lateral surface along a longitudinal extension, wherein the cladding is free of scattering elements; and
a light-emitting element configured to inject light into the first or second end, the transparent core having a scattering element that changes a propagation direction of the light in the transparent core,
the light guide having a light-blocking coating on at least part of the lateral surface of the core and having a light-transmissive portion along the longitudinal extension so that the light scattered on the scattering element and striking the light-transmissive portion escapes from the light guide, the light-blocking coating having a light transmittance that is lower than a light transmittance of the light-transmissive portion,
wherein the scattering element comprises a fiber-like light-scattering region extending linearly along the longitudinal extension.

2. The linear light source of claim 1 , wherein the cladding comprises a transparent cladding surrounding the transparent core.

3. The linear light source of claim 1 , wherein the light-blocking coating at least partially reflects or backscatter rays of the light incident on the lateral surface.

4. The linear light source of claim 3 , wherein the light-blocking coating comprises a metal coating.

5. The linear light source of claim 4 , wherein the metal coating has a thickness of at least 10 nanometers.

6. The linear light source of claim 3 , wherein the light-blocking coating comprises an ink layer.

7. The linear light source of claim 1 , wherein the light-blocking coating comprises an ink layer.

8. The linear light source of claim 7 , wherein the ink layer is a lacquer layer comprising pigment.

9. The linear light source of claim 8 , wherein the pigment comprises a fluorescent pigment.

10. The linear light source of claim 8 , wherein the pigment comprises a phosphorescent pigment.

11. The linear light source of claim 1 , wherein the light-blocking coating extends over the light-transmissive portion.

12. The linear light source of claim 11 , wherein the light-blocking coating is a structured coating in the light-transmissive portion such that the structured coating is partially transmissive to the light.

13. The linear light source of claim 12 , wherein the structured coating has a layer thickness of sufficient so that part of the light passes therethrough.

14. The linear light source of claim 1 , wherein the light-blocking coating comprises a plurality of longitudinal portions spaced along the longitudinal extension of the light guide and separated from each other.

15. The linear light source of claim 1 , wherein the linear light-scattering region is offset from a center of the core.

16. The linear light source of claim 15 , wherein the linear light-scattering region is offset towards a portion of the lateral surface opposite the light-transmissive portion.

17. The linear light source of claim 15 , wherein the linear light-scattering region is arranged such that the light emitted by the light guide is collimated by refraction on the lateral surface.

18. The linear light source of claim 15 , wherein the linear light-scattering region is arranged such that the light emitted by the light guide is collimated by reflection on the light-blocking coating.

19. A device comprising:
the linear light source of claim 1 ; and
a surface along which the light guide extends, wherein the light-transmissive portion is arranged with respect to the surface such that the light emitting from the light-transmissive portion is radiated away from the surface.

20. The device of claim 19 , wherein the surface has a recess within which the light guide extends, the light guide being fixed in the recess by a mounting profile.

21. A linear light source, comprising:
a light guide including a transparent core having a first end, a second end, and a lateral surface along a longitudinal extension; and
a light-emitting element configured to inject light into the first or second end, the transparent core having a glass rod scattering element that changes a propagation direction of the light in the transparent core, wherein the light guide is produced by forming a preform of two or more glass rods, wherein at least one of the glass rods contain light-scattering particles so as to define the glass rod scattering element,
the light guide having a light-blocking coating on at least part of the lateral surface of the core and having a light-transmissive portion along the longitudinal extension so that the light scattered on the scattering element and striking the light-transmissive portion escapes from the light guide, the light-blocking coating having a light transmittance that is lower than a light transmittance of the light-transmissive portion.

22. The linear light source of claim 21 , wherein the particles are defined by demixing or phase separation in the glass and/or may be formed from the glass.

23. A linear light source, comprising:
a light guide including a transparent core having a first end, a second end, and a lateral surface along a longitudinal extension;
a light-emitting element configured to inject light into the first or second end, the transparent core has a scattering element that changes a propagation direction of the light in the transparent core; and
a light-blocking coating on the lateral surface of the transparent core,
wherein the light guide is produced by forming a preform of two or more glass rods at least one of which comprises light-scattering particles, the light-scattering particles are defined by demixing or phase separation in the glass and/or are formed from the glass, and from drawing the preform such that light guide has a fiber-like light-scattering region that extends linearly along the longitudinal extension, and
wherein the light-blocking coating having a light-transmissive portion along the longitudinal extension so that the light scattered on the scattering element and striking the light-transmissive portion escapes from the light guide, the light-blocking coating having a light transmittance that is lower than a light transmittance of the light-transmissive portion.

24. The linear light source of claim 23 , wherein the light guide comprises a transparent cladding surrounding the transparent core.

25. The linear light source of claim 23 , wherein the light-blocking coating at least partially reflects or backscatter rays of the light incident on the lateral surface.

26. The linear light source of claim 25 , wherein the light-blocking coating comprises a metal coating.

27. The linear light source of claim 26 , wherein the metal coating has a thickness of at least 10 nanometers.

28. The linear light source of claim 25 , wherein the light-blocking coating comprises an ink layer.

29. The linear light source of claim 23 , wherein the light-blocking coating comprises an ink layer.

30. The linear light source of claim 29 , wherein the ink layer is a lacquer layer comprising pigment.

31. The linear light source of claim 30 , wherein the pigment comprises a fluorescent pigment.

32. The linear light source of claim 30 , wherein the pigment co

Assignees

• Schott Ag

Inventors

• Schabacker Stephan
• Woelfing Bernd

Classifications

• F21K9/61

  using light guides · CPC title

• G02B6/0041

  provided in the bulk of the light guide · CPC title

• F21Y2103/00

  Elongate light sources, e.g. fluorescent tubes · CPC title

• G02B6/001 Primary

  the light being emitted along at least a portion of the lateral surface of the fibre · CPC title

• G02B6/02338

  Structured core, e.g. core contains more than one material, non-constant refractive index distribution in core, asymmetric or non-circular elements in core unit, multiple cores, insertions between core and clad · CPC title