SU1645922A1 - Fibre-optical coupler - Google Patents

Abstract

The invention relates to optical fibers, and more specifically to optical means of connecting optical fibers, and can be used in optical fiber communication systems. The purpose of the invention is to reduce radiation losses, as well as obtaining a 1: 5 branch ratio for the optical signal power. The fiber-optic coupler consists of an input and two output light guides, with the front surface of the first output fiber, coaxial with the input fiber, angled (p to its axis). and made with an interference coating, the front surface of the input fiber is bevelled at the same angle p, and the second output fiber at an angle of 2 p at the angles O p S 45 °, and the connection area of the optical fibers is filled glue with a refractive index equal to the refractive index of the core material or the optical cladding of the fiber.The ratio of the parameters of the fiber-optic optical fiber providing the specified branching ratio is given. 1 s n, f-ly, 2 silt, SL

Description

The invention relates to optical fibers, and more specifically to optical means of connecting optical fibers, and can be used in optical fiber communication signals.

The aim of the invention is to reduce radiation losses, as well as to obtain a 1: 5 branch ratio for the power of the optical signal.

FIG. 1 shows a fiber optic coupler; in fig. 2 is a spectral characteristic for its branch ratio.

The fiber optic coupler consists of a common input light guide 1, which is bevelled at an angle p to its axis, and two output light guides 2 and 3, which have a bevel

at an angle (p l2 (p, respectively. The output light guide 2, coaxial with the common input fiber, is covered with an interference coating 4, consisting of two layers with refractive indices of 3.2 - 3.5 and 1.95 - 2.05 and with optical thicknesses equal to 0.15 AO, where Do is the working wavelength. The gaps between the ends of the optical fibers are filled with adhesive 5 having a refractive index equal to the refractive index of the core or optical cladding of the optical fiber.

The fiber-optic coupler is made by spraying a two-layer coating consisting of a silicon film with a refractive index onto the cut-off KKS 125/50 fiber line cut at an angle of 45 ± 2 °.

N SL

about

N5 GO

ny 3.3 and zirconia films with a refractive index of 2.02. The optical thickness of the films was 175 nm. The connection area of the optical fibers is filled with glue D-9 The free ends of the optical fibers are provided with optical connectors and the entire device is attached to the housing.

The radiation loss in the proposed hinge is 0.75 - 1.0 dB, which is 30% less than that of the prototype.

Claims (2)

Claim 1. Fiber optic coupler, consisting of a common input and two output fibers, the front surface of the first output fiber, coaxial with the common input, is bevelled at an angle p to its axis and made with an interference coating, characterized by the fact that . in order to reduce radiation losses, the end surface of the common the input fiber is beveled at an angle p, the second output fiber is beveled at an angle and is located at an angle to the axis of the common input fiber at 180 ° and at 45 ° p 180 °, and the connection area of the light guides is filled with glue with a refractive index equal to that of the core material or the optical cladding of light guides. 2. A coupler according to claim 1, distinguishing c. so that, in order to obtain a 1: 5 branch ratio for the power of the optical signal, the interference coating is made of two layers with refractive indices of 3.2 - 3.5 and 1.95 - 2.05, the optical thickness of which is 0.15 where Do is the working wavelength with p 45 ± 2 °. 0 five Ppy Fig 1 7 6 five i + 3 2 one about 600 700 800 900 YuOO VOO 200 then /1l.1 500 KZO isO, nn Editor E. Kopcha Fig 2 Compiled by A.Shmalko Tehred M. Morgental Proofreader M. Pojo