Device for optical fibers illumination

The present invention relates to improvements to devices for illuminating the optical fibers commonly called "light engines" or "light sources".

A light source generally comprises a lamp lighting and an optical device for concentrating the light rays on the end of optical fiber bundle, the source comprises Also a transformer if a low voltage lamp is used. All these elements are enclosed in a closed housing.

The rise in temperature inside the housing is unacceptable because the destruction of the fiber is to be feared. Therefore, one has to but ventilate the air that circulates inside the housing of the vehicle dust that settle with all the disadvantages that this can present.

The invention, which overcomes these inconvénie nts, is remarkable in that the light rays pass through an enclosure, dustproof at least consisting of a straight prism base triangular each face of the prism having an opening respectively closed by the front face of the usual lamp, by a mirror and a lens that focuses the rays to the end of the fiber bundle, said end being held outside the enclosure.

The mirror used is of the type that can be crossed by infrared rays. In this way, part of the heat, that reflected from the projector lamp and the lamp itself, leaves the enclosure, through the mirror, without reaching the beam. The other part is radiated from the outer face of the projector and the lamp cap which, according to the invention are located outside the enclosure.

The present invention will be better understood by the description will follow with reference to the accompanying drawings by way of example indicative only, in which:<ul><li>Figure 1 is a perspective view showing the shape of the support pregnant optical bodies;</li><li>Figure 2 is a vertical sectional view of a source according to the invention.</li></ul>

According to the invention, the organs needed to inform, in good conditions, the end of a bundle of optical fibers 1, are carried by a housing 2 having the shape of a right prism based triangular.

Each of the side faces 3, 4 and 5 of this housing has a opening respectively 6, 7 and 8. The surfaces 3 and 5 are arranged to right angle.

The opening 6 is closed by the front face of the reflector 9 of the usual lamp, said reflector and its base 10 being located outside Case 2.

The opening 7 is closed by a mirror 11, of a known type, kind of those having the property of being traversed by the rays infrared.

The opening 8 is closed by a lens 12 focusing the light rays, reflected by the mirror 11, on the end of the beam 1.

The warm rays reflected by the reflector of the lamp, freely through the mirror 11 and can not reach the end 1a of the beam.

By the provision of the lamp relative to the housing, the portion heat radiated by the outer surface of said lamp is dissipated in ambient air.

The lamps used are manufactured in large series and their characteristics are sometimes uncertain. Therefore, it is possible that some warm rays do not face the mirror 11 and cross the lens 12. According to the invention, they are cooled in the space 13 formed between the outer wall of the housing and the end 1a of the beam.

We also know, for the reasons mentioned above, that part of the light energy emitted by the lamp does not meet the mirror 11 or, in the known devices, is not returned to the lens 12.

According to another characteristic of the invention, which overcomes this disadvantage, all internal surfaces of the casing are reflective.

As is apparent from Figure 2, the housing 2 is tight at least dust. The sealing can be achieved using joints (Not shown), the holding bodies 9 and 12 being provided by circlip 14. With regard to the mirror 11, it can be maintained by gluing.

Triangular bases 15 can be molded with the faces 3 and 5 or be carried by the face 4.

For reasons of mechanical protection, the assembly just to be written above is held in a casing (not shown) made, for example, perforated sheet. this envelope can advantageously withstand the power transformer common (case of using a low voltage lamp) and, or, a color change mechanism.