Fiber-optic conversion module

Patent metadata

Field	Value
Publication number	US-9605825-B2
Application number	US-201514670012-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Sep 26, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

A fiber-optic conversion module is provided as part of a lighting device on a vehicle. The module includes optical fibers with connectors, a light exit head, and a converter mounted on a cooling element. Shorter wavelength excitation light is fed to the optical fibers that emit the excitation light towards the converter arranged at an angle relative to the beam direction, at a light spot that remits useful light in a radiation angle in form of a cone of useful light and reflects excitation light as a Fresnel reflection substantially outside the cone of useful light, where Fresnel reflection is made harmless by a light stop.

First claim

What is claimed is:

1. A fiber-optic conversion module, comprising:
at least one optical fiber having a light input end adapted for being connected to an associated excitation light source and a light exit end adapted for emitting excitation light to a light spot in a predetermined beam direction;
a converter arranged at an angle relative to the predetermined beam direction and used for converting shorter wavelength excitation light from the associated excitation light source into longer wavelength converted light and for emitting mixed useful light emanating from the light spot and spreading into a region of a useful radiation angle with a part of the excitation light being reflected at the converter into a region outside the useful radiation angle;
a light exit head for supporting the light exit end of the at least one optical fiber and the converter;
a cooling element for accommodating the converter in a heat conductive and mechanically stable connection with the light exit head; and
an exit window for useful light provided with a light stop for excitation light directly reflected at the converter outside the region of the useful radiation angle of the useful light.

2. The fiber-optic conversion module as claimed in claim 1 , wherein the exit window for useful light is defined by a cover sheet of the light exit head, the cover sheet comprising the light stop, which together with the converter forms a light trap for collecting the excitation light directly reflected at the converter.

3. The fiber-optic conversion module as claimed in claim 1 , further comprising a further optical fiber provided for optically monitoring the converter, the further optical fiber having a second light input end near the light exit end of the at least one optical fiber and a second light exit end near the light input end of the at least one optical fiber, wherein the second light exit end is connectable to a photodetector.

4. The fiber-optic conversion module as claimed in claim 1 , wherein the at least one optical fiber comprises two or more optical fibers supported in a manifold housing at least partly forming a curve and extending along a rectilinear or slightly curved line toward a light exit concentration point from which the exiting excitation light reaches the light spot.

5. The fiber-optic conversion module as claimed in claim 1 , wherein the at least one optical fiber is enclosed by at least one protective tube and/or layer.

6. The fiber-optic conversion module as claimed in claim 5 , wherein the protective tube and/or layer has two sections that engage telescopically into and above each other to provide for a compensation in length between the optical fiber and the protective tube.

7. The fiber-optic conversion module as claimed in claim 4 , wherein the manifold housing encloses a crescent-shaped inner space in which the two or more optical fibers extend in a curve between the associated excitation light source and an optical fiber connecting cable to the light exit head.

8. The fiber-optic conversion module as claimed in claim 4 , wherein, between the associated excitation light source and the light exit head, the two or more optical fibers partially extend along a helical line or form a loop.

9. The fiber-optic conversion module as claimed in claim 4 , wherein the two or more optical fibers comprise three optical fibers, each of which is individually surrounded by a metallic protective tube between a respective associated connector and the manifold housing, and which are combined in a shared metallic protective tube between the manifold housing and the light exit head.

10. The fiber-optic conversion module as claimed in claim 9 , wherein the further optical fiber is surrounded by a further metallic protective tube between a further connector and the manifold housing and extends in the shared metallic protective tube together with the three optical fibers between the manifold housing and the light exit head.

11. The fiber-optic conversion module as claimed in claim 1 , wherein the at least one optical fiber has a quartz glass fiber core, a quartz glass fiber cladding, and a coating comprising two layers of different plastics or of plastics and metal.

12. The fiber-optic conversion module as claimed in claim 1 , wherein, at the light input end, the at least one optical fiber has a ferrule with a connecting end portion provided with a crimping region surrounding the connecting end portion and/or with a protective aperture stop covering an end face of the ferrule and/or with a ceramic socket surrounding the fiber end at the connecting end portion, or wherein, in the region of the ferrule, the fiber cladding of the at least one optical fiber is of such a thickness that in case of misalignment of the connector with respect to the associated excitation light source the excitation light is still safely trapped on the ferrule end face.

13. The fiber-optic conversion module as claimed in claim 3 , wherein the light exit head comprises a lower part, an upper part, and an insert, which supports the ends of the at least one optical fiber and the further optical fiber proximal to the converter so as to form a light exit concentration point for delivering the excitation light to the light spot.

14. The fiber-optic conversion module as claimed in claim 1 , wherein the cooling element of the light exit head is connected to a heat sink via a heat conduction path.

15. The fiber-optic conversion module as claimed in claim 1 , wherein the light exit head has a housing step at the light exit end of the optical fibers facing an inclined surface of the cooling element on which the converter is attached.

Assignees

• Schott Ag

Inventors

• Wölfing Bernd
• Hagemann Volker
• Meinl Jürgen
• Russert Hubertus
• Reichert Thomas

Classifications

• F21S41/285

  Refractors, transparent cover plates, light guides or filters not provided in groups F21S41/24 - F21S41/2805 · CPC title

• F21S45/47

  Passive cooling, e.g. using fins, thermal conductive elements or openings · CPC title

• F21S45/70

  Prevention of harmful light leakage · CPC title

• F21S41/10

  characterised by the light source · CPC title

• F21S41/19

  Attachment of light sources or lamp holders (achieving variable light distribution by movable light sources F21S41/657) · CPC title