SU1493971A1 - Fiber-optical splitter - Google Patents

Abstract

The invention relates to fiber optics, reduces losses and improves the reliability of splitters on quartz-polymer fibers. A polymeric sheath is removed from the end portions of the fibers 2 and a reflective metallic coating 6 is applied. As a result, the filling ratio of the beam increases and the strength of attachment of the beam to the mixing rod 1 increases. The ratio for the thickness of the coating is given in the description. 2 Il.

Description

The invention relates to fiber optics and can be used in light guide communication systems and information transmission.

The purpose of the invention is to reduce optical losses and increase the reliability of the splitter.

Figure 1 shows a longitudinal section of a splitter with a plane passing through the axis of the mixing rod; figure 2 - section aa on

figure 1.

The fiber optic splitter (Fig. 1) contains a mixer 1, for example a glass 1 and 1 cylinder, and a bundle of light guides 2 connected to it, which consist of core 3, polymer 4 and protective 5 shells, and also has a metallic reflective coating 6 applied to cores of the end sections of light guides adjacent to the input end of the optical mixer 1. The lateral surface of the optical mixer 1 is covered with a reflective sheath 7, and the rear end can be connected to a reflecting mirror 8, have a mirror coating, or tykovan with the second beam.

Splitter works as follows.

The radiation emitted from any light guide 2 enters mixer 1 and, reflected from the light reflecting shell 7 and mirror 8, is evenly distributed over the end of the bundle, which makes it possible to transmit or receive an optical signal from any other light guide 2 from all other fibers 2.

An example of a specific embodiment is a fiber optic branch4.

;about

SAE

:WITH

3

Vitol, a bundle of which has a hexagonal circle and a new piling of light guides (made of nineteen standard multimode quartz - polymer light guides with a stepped refractive index profile, numerical aperture NA 0.3, with a core diameter and a reflective polymer cladding respectively 200 and 300 microns . From the sections of the optical fibers adjacent to the optical mixer, a polymer reflective sheath was removed at a length of 0.5 cm and a metallic, for example, silver coating chemically deposited on the core The specific optical losses with a P of 0.5 dB / cm. The bonding of metallized light guides in the bundle is carried out, for example, by gluing together epoxy resin. The end of the bundle is connected to the input end of an optical mixer, which is a segment of a round optical fiber 30- 40 mm with polished ends, with a core of 5 D in diameter, where D is the total diameter of the optical fiber (the core is a shell made of optical glass and the shell is 0.5 MW thick.

Rear Highlander mixer has an aluminum mirror coating. The magnitude of the optical loss of such a ramifier, due to the incomplete filling of the beam with the cores of the optical fibers, is determined by the formula

- 10 Ig

S,

(one)

H

where H5ser is the sum of the areas of the cores of the optical fibers of the beam;

S peach beam area. Consequently, the magnitude of the decrease in losses of a splitter containing metallic metallized light guides, as compared to a splitter containing quartz — polymer light guides,

will be:

S p

- IU IP, -,

LP

(2)

R | M

the cross-sectional area of the beam with the polymer shell; Beam section with metal coating.

However, the metallic coating introduces additional losses equal to:

oi.

Aon

2 IP

(3)

Moreover, the increase in the light transmission of the splitter with metallized optical fibers, achieved due to the more dense packing of the beam and determined by (2), should exceed the optical losses introduced by the metal coating, i.e. the condition must be met:

 oL oi Arp (A)

Substituting in (4) the expressions (2) (3), we obtain

and

10 Ig

B G1M

IP

0

five

0

five

0

Claims (1)

Invention Formula A fiber-optic splitter containing at least one bundle of quartz-polymer light guides coupled at the end with an optical mixing rod, characterized in that, in order to reduce optical loss and increase the reliability of the splitter, metal ends are applied to the end portions of the cores of quartz-polymer light guides. reflective coating, and the thickness of the coating is chosen such that to satisfy the condition: Where 10 Ig Snn S P M 1 SOM IP p is the cross-sectional area of the beam with the polymer shell; metal beam coated sectional area; the length of the metal coating of the core; specific loss of light guides by metal coating. Fiel Fie.2