JPS6052804A - Optical multiplexer and demultiplexer for optical communication - Google Patents

Abstract

PURPOSE:To decrease the number of adhering points and to improve the characteristic resistant to moist environment by providing a pair of holders and fixing selfoc lenses and ferrules. CONSTITUTION:A selfoc lens 3 and a ferrule 2 are grasped and fixed together from above and below by means of a pair of holders 24 and 25. The adhering points for each one demultiplexing channel are seven points; between a central glass block 5/a lambda1 wavelength selecting filter 6, between the filter 6/a spacer block 4, between the block 4/the selfoc lens 3, between the lens 3/the ferrule 2, between the lens 3, the ferrule 2/the lower holder 24 for fixing commonly the positions of 2, 3, between the holder 24/the upper holder 25 for fixing and between the holder 25/a glass base 14. The adhering points in this example are total twenty-two points with four channels and are less by light points than the adhering points of the conventional construction.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an optical multiplexer/demultiplexer used in a transmission means for original communications to combine, separate, and separate multiple types of original signals. .

[Background of the invention]

FIG. 1 is a plan view of a conventional optical multiplexer/demultiplexer, FIG. 2 is a sectional view taken along line D-J)' in FIG. 1, and FIG. 6 is a partially enlarged view.

Three types of optical signals λ8. λ7. When the composite signal 1 of
One signal λ can be extracted by passing through the glass block in the order of spacer block 4 → cell hook lens 3 → ferrule 2 → branching station A9. The other optical signals λ, , λ3 are λ
It is reflected by wavelength selection filter 6, demultiplexed again by wavelength selection filter 10, and guided to demultiplexing station B11. The last optical signal λ3 is similarly reflected by the selection filter 10 and transmitted to the demultiplexing station C12. This means that the input optical signals of six different wavelengths have been demultiplexed to three stations. The above action is reversible, and the optical signal is transmitted in the reverse order of the optical path.
In other words, it also has the function of sending each wavelength signal to one station (combining). Further, each member of the optical path system is fixed by a respective position fixing holder.

The fixed state of the optical members regarding the branching station A9 will be explained with reference to FIG. The bonding points of the constituent members are determined by each original signal λ8. λ2. In addition to the central block 5 and the glass space 14, which are common members through which λ passes, the following (α) to (A
). i.e. α) central block 5/λ
1 wavelength selection filter between 6 16. λ, wavelength selection filter 16/spacer block 4 interval 17. C) Spacer block 4/Self-hook lens 5 gap 1B, d) Cell-hook lens 3/Lens position fixing holder 8 gap 19. g
) Between lens position fixing holder 8/glass space 14 2
0. f) Self-hock lens 3/ferrule 2 M21
．． g) Between ferrule 2 and ferrule position fixing holder 7 22. A) Between the position fixing holder 7 and the glass space 14: 23 degrees As mentioned above, there are 8 bonding points for one branch station, so if two branch stations are installed, the bonding points will be as shown above ( 8 locations). Conventionally, these Ω points were fixed with adhesive. In such a configuration, it takes time for the adhesive to harden, resulting in poor working efficiency and the finished product being expensive. Furthermore, the large number of bonding points causes the problem that optical loss cannot be reduced. Even if the product is completed and adjusted to minimize the amount of light loss, peeling may occur at the adhesive interface when subjected to a humidity environment test (50°C, 95% RH), which is one of the reliability evaluation tests. There was a problem in that the amount of optical loss increased, resulting in defects.

[Purpose of the invention]

An object of the present invention is to provide an optical multiplexer/demultiplexer which has a reduced number of bonding points, is lower in cost than the conventional one, and has excellent moisture resistance characteristics.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described with reference to FIGS. 4 to 6. FIG. 4 is a plan view of one embodiment of the optical multiplexer/demultiplexer of the present invention, FIG. 5 is a sectional view taken along line D-D' in FIG. 4, and FIG.
It is an EE' sectional view.

The cell-hook lens 3 and ferrule 2 in the conventional device are each mounted in a holder 7. as shown in FIGS. 1 to 3.
However, in this embodiment, a pair of holders 24.25 are provided as shown in FIG. It is fixed by holding it together from the top and bottom.

λ厘、λ2． The optical signal 1 in which the three wavelengths of λ3 are combined is transmitted through the ferrule 2 in the optical multiplexer/demultiplexer → cell-hock lens 3 → spacer block 4 → center block 5 → λ1 wavelength selection filter 6 → spacer block 4 cell-hock lens 6 → ferrule One signal λ can be extracted by passing through each component in the order of 2→λ1 branching station A9. Another signal λ2. λ3 is reflected by the λ□ wavelength selection filter 6, and is reflected by the λ22 wavelength selection filter 1.
The signal is branched again at 0 and guided to the branching station B11. The final signal λ3 is reflected by the λ22 wavelength selection filter 10 and transmitted to the demultiplexing station C12. In this manner, the apparatus of this embodiment operates optically in the same manner as the conventional apparatus (FIGS. 1 to 3). In this embodiment, as shown in FIGS. 5 and 6, the bonding points for one demultiplexing station are α) central glass block 5/λ, wavelength selection filter 6,
Between the wavelength selection filter 6 and the spacer block 4, c) Between the spacer block 4 and the cell-hoc lens 3, t) Between the cell-hoc lens 3 and the ferrule 2, e) Between the cell-hoc lens 3
．． Ferrule 2/2.3 co-position a! Lower fixing holder 24
f) Lower fixing holder 24/upper fixing holder 25
g) There are seven locations between the lower fixing holder 25 and the glass space 14. As a result, there are a total of 22 bonding points for the four stations, which is 8 fewer bonding points than the conventional structure. In addition, here, the cell-hock lens 3 and the ferrule 2 are glued together to send signals into the optical fiber, but it is also possible to use a cell-hock lens with an optical fiber that performs the functions of these two parts in one part. On the other hand, with the conventional type, there is a self-hock lens 3. Separate fixing holders 8 and 7 for ferrule 2
It was fixed.

Therefore, it is necessary to adjust the original axis, and in addition, the self-hock lens 2. The adhesive layer such as the ferrule 3 comes into direct contact with air. Therefore, when a moisture resistance test is performed, the adhesive immediately absorbs moisture and peels off at the adhesive interface, which increases the amount of light loss and results in a defective product. Therefore, in the main metal demultiplexer of this embodiment, the metal case 15 is filled with a resin 26 having a low moisture permeability, for example, an epoxy resin, and the entire metal case is made into a sealed structure to improve moisture resistance and high reliability.

Figure 7 shows how the light transmission loss changes over time when a humidity environment test is conducted at a temperature of 50°C and a humidity of 95%, where the solid line is the conventional product, the broken line is the above-mentioned example, and the chain line is the passing line. It is.

〔Effect of the invention〕

As described in detail above, the optical multiplexer/demultiplexer of the present invention has excellent practical use in that it can reduce the number of bonding points for optical components, significantly improve moisture resistance, and reduce manufacturing costs. It has the desired effect.

[Brief explanation of drawings]

FIG. 1 is a plan view of an example of a conventional principal demultiplexer, FIG. 2 is a sectional view taken along line DD' in FIG. 1, and FIG. 3 is a partially enlarged view of FIG. 2. Fig. 4 is a plan view of one embodiment of the principal metal splitter of the present invention, Fig. 5 is a sectional view taken along line B-n' in Fig. 4, and Fig. 6 is the same (
The E-E' sectional view and FIG. 7 are charts showing the results of the humidity-resistant environment test. 1... Combined optical signal 2... Ferrule 6...
・Self-hock lens 5...Central block 6...λ
, wavelength selection filters 24, 25...a pair of holders, 26...resin as a filler.

Claims (1)

[Claims] t In an optical multiplexer/demultiplexer having a glass block equipped with a filter for selecting an optical signal, a cell-hoc lens, and a ferrule, a pair of holders that clamp and fix the cell-hoc lens and ferrule. 1. An optical multiplexer/demultiplexer for communication, characterized in that a cell-hock lens and a ferrule are fixed by the holder. 2. The above-mentioned optical multiplexer/demultiplexer is characterized in that a filling material is injected into the gap between the optical members stored inside to bury and seal the optical members. Optical multiplexer/demultiplexer for optical communications.