DD148390A1 - ARRANGEMENT FOR INPUTING LIGHT IN A LIGHT GUIDE - Google Patents

Abstract

The optical communication technology requires dazzling elements, crossovers and branches in large numbers, which can be easily manufactured with high stability. Known technical solutions have a relatively high adjustment effort and a high Grunddaempfung. The erfindungsgemäaesze arrangement has low adjustment effort, high stability and low Grunddaempfung. The solution consists in the fact that the end faces of two in-plane, closely adjacent light guides are fixedly connected to an optically permeable body which has a spherical surface provided with a reflective coating on the surface opposite the end faces.

Description

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Berlin, 12.12.79 Ze / Ks 29170 /

applicants

Arrangement for coupling light into a light guide

field of use

The invention relates to an arrangement for coupling light from a light guide into another light guide, wherein at the same time the use as an attenuator, branch element or crossover in the optical communication or measurement technology is possible.

Characteristic of known technical solutions

Arrangements for coupling light from one light guide to another are known.

In DE-OS 2 655 114 rod lenses are used for coupling and coupling of light in optical fibers. Are then placed between the rod lenses damper discs, interference filters or ^r j? Ei ~ lerspiegel arranged.

Even the use of individual concave mirrors for. Coupling in light guide has been proposed, wherein in the

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free space between the optical fiber end faces and the concave mirror, for example, a measuring zone for measuring vapor absorption is provided or damping Soheiben, splitter mirrors or interference filters are arranged. The "known arrangements have the following disadvantages for the optical communication technology.

Stablinsenanordnungen require a very high adjustment effort of the light guide with respect to the rod lenses on the one hand and with respect to the rod lenses with each other on the other hand. The aberrations of the lenses also cause loss of attenuation which can only be eliminated by the very complex production of aspherical surfaces.

Although concave mirror arrangements have lower imaging losses when the optical fibers are positioned close to the axis, the two optical fiber ends must be positioned with high accuracy in the three spatial directions with respect to the concave mirror, since the stability of this positioning over a wide temperature range (-25 ⁰ C to +55 ⁰ C) must be constant. The reflection coating of the concave mirror is also not protected against atmospheric influences.

Object of the invention

The aim of the invention is to provide an arrangement for coupling light from one light guide into another light guide, in which a concave mirror is inseparably part of the light transmission and coupling medium.

Essence of the invention.

The invention has for its object to couple light from a light guide into another light guide so that optimal Einkoppelverhältnisse and high temperature and time stability are ensured with the simplest adjustment of the optical fiber end surfaces in one plane.

This object is achieved in that the close together lying in a plane end surfaces of two

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Optical fiber with a body of optically transparent material. Rial are firmly connected to the end faces of the light guide opposite surface has spherical shape and is provided with a light-reflecting coating. This reflective coating is partially permeable and / or frequency-selective. ,

embodiment

The invention will be explained in more detail with reference to the drawing reproduced embodiments. In the drawing show:

Pig. 1: a schematic section through the inventive arrangement, which also acts here as an attenuator,

Pig. 2 shows a schematic section through the arrangement according to the invention in expanded Porm.

In Pig. 1, two closely adjacent light guides 1, 2 are cemented with their end faces 5, 6 to a square face of, for example, a cuboid glass body 3. The glass body 3 is provided at the opposite end with a spherical surface, which has a reflective coating 4. Spherical surfaces and surface 4 act as a concave mirror. The distance between the optical fiber end surfaces 5j6 and the apex of the curvature of the spherical surfaces is equal to the radius of curvature of the spherical surfaces.

Light emerging from the light guide 1 propagates conically in the glass body 3 and is reflected on the reflective coating 4 in such a way that this light is coupled into the light guide 2. The same applies to the light from the light guide 2, which is coupled into the light guide 1. The degree of coupling is essentially determined only by the reflectance of the pad 4, so that, for example, at 50 fo reflection, the arrangement acts as a 3 dB attenuator. The adjustment is made by changing the reflectance of the reflective coating 4. The reflection by the reflector

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4 coating still passing light can be registered by a 'light-sensitive device and evaluated for measurement purposes.

If the reflective coating 4 is frequency-selective, the arrangement operates as a crossover.

Pig. 2 also shows two light guides 1, 2 whose end faces 5, 6 are attached to a glass body 3 according to Pig. 1 are angekittet. Since it is necessary in certain cases to parallelize the light passing through the reflective coating 4 or to direct it to other optical fibers or optoelectronic components, the spherical surfaces of the glass body are aplanatic for the light from the optical fibers 1, 2, that is, neither collects nor scattered, a second of the spherical surfaces of the glass body 3 adapted glass body 7 is disposed downstream of the first glass body 3. The second glass body 7 may be provided with a spherical or aspherical plan whose radius of curvature is dimensioned so that the passing through the lining 4 light is parallelized or focused.

Claims (3)

Experience san spruch 1. Arrangement for coupling Lioht into an optical waveguide, in which a concave mirror is an inseparable component of the light transmission and coupling medium, characterized in that the end faces (5, 6) of two light guides (1, 2) lying close together in one plane ) are fixedly connected to a body (3) made of optically transparent material, whose surface (5; 6) of the light guides (1; 2) has a spherical surface and is provided with a light-reflecting coating (4). 2. Arrangement * naoh point 1, characterized in that a to the spherical surface of the glass body (3) adapted second body (7) of optically transmissive material is arranged downstream of the first body (3), of which the spherical surface of the first body (3 ) opposite surface is formed spherically or aspherically. 3. Arrangement according to item 1, characterized in that the reflective coating (4) is formed partially permeable and / or frequency selective.