JPH0350507A - Manufacture of fusion drawn type optical coupler - Google Patents

Abstract

PURPOSE:To obtain the fusion drawn optical coupler which has a target value at high yield by fixing one end of an optical coupler main body together with presser jigs, and making the other end rotatable and fixing it after the characteristics are adjusted. CONSTITUTION:An optical coupler main body 5 is put in a glass pipe 1, optical fiber parts 6 and 7 are inserted into the center holes A of presser jigs 2 and 3 consisting lid-shaped metal fittings at both ends, and the part is fixed with resin 4. Then, the annular edge B of one presser jig 2 is fixed to the peripheral surface of the glass pipe 1 with resin 4 and the other presser jig 3 is made rotatable. After the resin setting, the other presser jig 3 is rotated to correct the twist of the optical fiber part 7 so that the branch ratio, extinction ratio, and insertion loss are in initial characteristic states. Then the part B of the presser jig 3 is sealed with the resin 4 and the coupler is completed. Consequently, the fusion drawn optical coupler which has the target value is obtained at high yield.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical coupler, particularly a method for manufacturing a fusion-stretched optical coupler. [Prior Art] Conventionally, when mounting a touch-stretch type optical coupler body in a glass pipe, (1) the optical coupler body obtained by fusion-stretching is divided into one piece of halved glass pie 2; After transferring it to a glass pipe and fixing it with resin etc., cover it with another piece of halved glass pipe and attach it to the same tree. Alternatively, (2) leave the optical coupler body in the manufacturing equipment without moving it, bring the halved glass pipe piece to the optical coupler body, and fix it with resin. It's being done. [Problem to be solved by the invention] However, the above (1)! ! ! With this method, there is a problem that because the fused and stretched part is thin, twisting is added when fixing it to the halved glass pipe, which deteriorates the characteristics of the optical coupler. In addition, the characteristics of the optical coupler change depending on whether it is attached to the manufacturing equipment or when it is removed.
There is a problem that the optical fog cannot be obtained as per the target value.
This is due to the influence of the pressure caused by the optical fiber holding jig in the manufacturing equipment and twisting during manufacturing. In addition, with the above manufacturing method (2), there is no effect such as twisting due to the movement of the optical coupler wood, but the characteristics of the optical coupler change before and after mounting, making it impossible to obtain an optical coupler that meets the target value. There's a problem. This is also caused by the effects of lateral pressure from the optical fiber holding jig in the manufacturing equipment and twisting during manufacturing. SUMMARY OF THE INVENTION An object of the present invention is to provide a manufacturing method that eliminates the drawbacks of the prior art described above and allows a fused and drawn optical coupler to be obtained in accordance with target values with a high yield. [Means for Solving the Problems] The method for manufacturing a fusion-stretched optical coupler of the present invention includes storing an optical coupler body obtained by fusing and stretching a plurality of wavefront preserving optical fibers in a cylindrical container. One end of the optical coupler body is fixed together with a holding jig, and the other end is made to be able to rotate together with the holding jig.After adjusting the characteristics by rotating the holding jig at the other end, the other end of the optical coupler body is fixed. The end is fixed together with a holding jig. [Operation] When storing and fixing the optical coupler body in a cylindrical container, one end of the optical coupler body is fixed together with the holding jig, but the other end is left in a state where it can rotate together with the holding jig. Therefore, when the holding jig at the other end is rotated, the optical fiber portion of the optical coupler body is twisted together with it, allowing the characteristics to be adjusted. Therefore, a melt e-stretched optical coupler meeting the target value can be obtained with a high yield. [Example] The manufacturing method of the present invention will be explained below based on the illustrated example. First, multiple polarization-maintaining optical fibers are fused and stretched to obtain an optical fiber main body with desired characteristics. In this example, two elliptical optical fibers with their characteristic axes aligned are fused and stretched to zero.
．． We manufactured an optical coupler body for 85μ. At this time, when the optical coupler body is attached to the manufacturing equipment, the branching ratio is 51x, the extinction ratio is -27 dB (transmission side), and -29 dB [coupling In! l). The insertion loss was 0.3dB. Note that the characteristic value in this state is almost equal to the target value. Next, remove the optical coupler body from the manufacturing equipment. In the case of this example, the characteristics of the optical coupler body at this time are a branching ratio of 55z
, extinction ratio -25dB+transmission side). -26dB (coupling side). The insertion loss was 0.36dB. Next, the optical coupler body removed from the above manufacturing apparatus is stored in a cylindrical container, one end is fixed together with a holding jig, and fl! ! Make sure that the end can rotate with the presser jig. In this example, as shown in FIGS. 1 and 2, the optical coupler main body 5 removed from the manufacturing apparatus has an inner diameter of 3. 5nl, outer diameter 5nm, length 20l
Insert the optical fiber part 6 into the central hole A of the holding jig 2.3 consisting of lid-shaped metal fittings at both ends.
7 and fixed that part with resin 4. Further, as shown in FIG. 3, only the annular edge B of the presser jig 2 at one end is fixed to the circumferential surface of the glass pipe l with resin 4, and the presser jig 3 at the other end is fixed with resin 4. It was designed so that it could be rotated without being fixed. After the resin hardens, fl is ready to rotate! ! By rotating the holding jig 3 at the end as shown in FIGS. Extinction ratio. The insertion loss is now a characteristic of the initial state. Then, as shown in FIG.
A perfect fused and stretched optical plastic 8 was obtained by fixing it with resin.
As a result, we were able to obtain a fused and drawn optical coupler with a good yield, meeting the target values. In this example, the resin used was urethane maxolate, and the holding jig was made of plastic. [Effects of the Invention] As described above, according to the present invention, there is no deterioration of characteristics during mounting, a fused and stretched optical coupler that meets the target value can be obtained with a high yield, and a fused and stretched optical coupler can be obtained with high yield. Cost reduction can be achieved.

[Brief explanation of drawings]

Figures 1 to 6 show the manufacturing method of the present invention. Figure 1 is an open view of the optical plastic showing the first mounting process, and
The figure is an end view, Figure 3 is a side view of the optical coupler showing the second mounting process, Figure 4 is a side view of the optical coupler showing how to adjust the characteristics, Figure 5 is its end view, and Figure 6 is a side view of the optical coupler. is a side view showing the completed fusion-stretched Hikari Kagura. In the figure, 1 is a glass pipe, 2 and 3 are holding jigs, 4 is a resin, 5 is an optical coupler body, 6.7 is an optical fiber portion, and 8 is a fused and stretched optical coupler. Figure 1 B Figure 3 Figure 4 Figure 6 Figure 2 Figure 5

Claims (1)

[Claims] 1. The optical coupler body obtained by fusing and stretching multiple polarization-preserving optical fibers is stored in a cylindrical container, one end of the optical coupler body is fixed with a holding jig, and the other end is fixed with a holding jig. Manufacturing a fusion-stretched optical coupler characterized in that the other end of the optical coupler body is fixed together with the holding jig after adjusting the characteristics by rotating a holding jig at the other end. Method.