JPS6256488B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical device used in an optical communication system and the like, and particularly relates to the structure of components of an optical device and its mounting structure.

In optical communication systems, various optical devices such as optical branchers, optical couplers, optical demultiplexers, optical multiplexers, optical switches, and optical attenuators are used. Such optical devices generally branch, combine, demultiplex, and demultiplex light.
Optical functional components that perform functions such as multiplexing, switching, and attenuation,
An optical input/output component for optical input/output to and from the optical functional component is mounted on a substrate.

[Conventional technology]

As optical input/output components in the above-mentioned optical devices, so-called pigtail type components, in which an optical lens system is coupled to one end of an optical fiber and an optical connector is coupled to the other end, are commonly used. In this case, the optical fiber is usually reinforced with a reinforcing fiber such as Kevlar (registered trademark of DuPont, hereinafter the same) in order to protect it from various loads acting on it.

An example of a conventional optical device using such a pigtail type optical input/output component is shown in FIGS. 3 and 4. This optical device is an optical demultiplexer,
FIG. 3 is a plan view schematically showing the overall configuration, and FIG. 4 is an elevational sectional view of the main parts. In these figures, reference numeral 1 indicates a metal substrate, on which a filter 2 having an optical demultiplexing function, an optical input component 3,
and optical output components 4 and 5 are mounted. still,
A two-dot chain line 21 indicates a protective cover. The filter 2 is well known in itself, so detailed illustrations and explanations will be omitted, but a non-reflective film is pasted on both sides of the prism, and one side has a filter that allows light with a certain wavelength λ1 to pass through, but other than that. A dielectric multilayer film is used to reflect light of a given wavelength, and on the opposite side there is another light of a certain wavelength λ2.
A dielectric multilayer film is attached to each layer that allows light of wavelengths to pass through but reflects light of other wavelengths.
In the illustrated example, when light including light with wavelengths λ1 and λ2 enters from the optical input component 3, the light with the wavelength λ1 is output from the optical output component 4 due to the demultiplexing function of the filter 2, and the light with the wavelength λ2 is The light is emitted from the output component 5 and demultiplexed.

The above-mentioned optical input/output parts 3, 4, and 5 all have the same structure, and as shown in FIG.
is inserted into the hole of the metal ferrule 8 with a portion thereof exposed, and is fixed by filling with adhesive. A lens 9 having a hemispherical end and a flat end is coupled to the tip of the ferrule 8 via a metal sleeve 10. Further, an optical connector 11 (see FIG. 3) for optical input/output is coupled to the other end of the optical fiber 6. Further, the optical fiber 6 is coated with a coating 12 of vinyl or the like, and is coated with Kevlar (reinforcing fiber).
It is reinforced with 13. The tip of the Kevlar 13 is partially exposed, and is inserted between the inner surface of the metal sleeve 14 attached to the outside of the vinyl coating 12 and the outer surface of the ferrule 8, and is fixed by being filled with adhesive. This protects the optical fiber 6 from damage due to external forces or thermal loads acting on it. The optical input/output components 3, 4, and 5 are all fixedly supported on the substrate 1 by adhesive via metal support members 15, 16 at the optical lens system coupling portion and the Kevlar coupling portion, respectively. Furthermore, since it is necessary to accurately position the optical axes of the optical lens system joints of the optical input/output components 3, 4, and 5, the support member 15 is wedge-shaped to facilitate positioning when fixing it to the substrate 1. It is designed so that

[Problem that the invention seeks to solve]

In the above conventional technology, the optical input/output components 3,
The optical lens system connecting parts 4 and 5 and the Kevlar fixing part are connected to each other, which causes the following problem. That is, the Kevlar 13 is adhesively fixed to the ferrule 8, and therefore, when a load is applied to the Kevlar 13, the load acts on the optical lens joint through the ferrule 8, causing positional deviation of the optical lens joint (optical axis). misalignment, movement in the optical axis direction, etc.). Another problem is that stress accumulated in the optical lens coupling portion due to environmental changes, particularly temperature changes, is difficult to release.

Furthermore, in the above conventional example, the optical input/output components ferrule 8, sleeve 8, and sleeve 14 are all made of metal, and the supporting member 1 is also made of metal.
5 and 16 on a common metal substrate 1. However, in recent years, especially the coupling parts of the optical lens system coupling part, that is, the ferrule 8 and the sleeve 10, have been made of materials substantially the same as the fiber wire 6 and the lens 9, such as ceramic material, in order to improve the precision of component dimensions and positioning. often. In this case, if the optical functional components and the optical input/output components are all mounted on a common metal substrate, there is a problem that the resistance against external loads, especially vibrations and shocks, or temperature cycles is weak.

[Means for solving problems]

The present invention provides an optical functional component as described above, and a pigtail type optical input/output component for optical input/output to the optical functional component, which is formed by coupling an optical lens system to one end of an optical fiber and reinforcing the optical fiber with Kevlar. ,
In order to solve the above-mentioned problems in an optical device including the optical functional component and a substrate on which the optical input/output component is mounted, an optical lens system coupling portion to the optical fiber in the optical input/output component and an optical fiber to the optical fiber are provided. The Kevlar fixing parts are independent from each other, and the optical input/output components are individually fixed to the substrate by the Kevlar fixing part and the optical lens system coupling part.

According to this structure, since the optical lens system coupling part and the Kevlar fixing part of the light input/output component are mutually independent, the load acting on the Kevlar is not transmitted to the optical lens system coupling part, and the optical lens system coupling part can prevent misalignment.

Furthermore, in the above optical device, in order to solve the above problem, the present invention provides that the optical lens system coupling portion to the optical fiber and the Kevlar fixing portion to the optical fiber in the optical input/output component are independent of each other. Furthermore, the coupling member for coupling the optical lens system to the optical fiber is made of a material substantially equivalent to the optical fiber or the lens, and the optical lens system coupling portion of the optical functional component and the optical input/output component is made of glass or glass. They are fixed to a common substrate made of the same material, the substrate is mounted on a metal support plate through a buffer layer made of a flexible material, and the Kevlar fixing parts of the optical input/output components are fixed to the metal support plate. It has a structure that allows for

According to this configuration, the optical device functional part including the optical functional part and the optical lens system coupling part of the optical input/output part is mounted in a so-called floating state with respect to the support plate, so that it is free from external loads and temperature cycles. High resistance to

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention, and shows the configuration of essential parts when the present invention is applied to the optical demultiplexer shown in FIG. 3 in comparison with FIG. 4. In FIG. 1, parts that are the same as or similar to those shown in FIGS. 3 and 4 are designated by equivalent numbers.

In FIG. 1, the structure of the optical lens system coupling portion of the optical input/output components 3, 4, and 5 to the optical fiber 6, that is, the ferrule 8, lens 9, and sleeve 10 is the fourth.
This is the same as the case shown in the figure. On the other hand, Kevlar 13 is
A second ferrule 17 is attached to the optical fiber 6 at a distance from the ferrule 8 of the optical lens system coupling portion.
and the sleeve 14, and are fixed by being filled with adhesive. That is, the optical lens system coupling part and the Kevlar fixing part are not connected to each other as shown in FIG. 4, but are independent from each other. The optical lens system coupling section and the Kevlar fixing section are individually fixedly supported on the substrate 1 by support members 15 and 16, respectively.

Therefore, even if a load is applied to the Kevlar 13 from the outside, this load does not directly act on the optical lens system coupling part, and the positional shift of the optical lens system coupling part is prevented. Moreover, the stress accumulated in the optical lens system coupling part is easily released to the free part of the optical fiber 6 between it and the Kevlar fixing part, improving environmental resistance.

Next, FIG. 2 shows a second embodiment of the present invention, and is a cross-sectional elevational view showing the overall structure of an optical demultiplexer having basically the same function as that described above. The optical input/output components 3, 4, and 5 (only 4 and 5 are shown in the figure) in this embodiment have a component configuration as shown in FIG.
That is, the ferrule 8A and the sleeve 10A are not made of metal, but of a material equivalent or substantially equivalent to the fiber wire 7 (see FIG. 1) or the lens 9, such as ceramics. The filter 2 and the optical lens system coupling parts 3, 4, and 5 are mounted not on a metal substrate but on a common substrate 1A made of glass or an equivalent material. In this case, the support member 15A of the optical lens system coupling portion is also made of glass or an equivalent material. The substrate 1A is fixed to a metal support plate 20 via a buffer layer 18 made of a flexible material such as a silicone adhesive. This support plate forms the bottom box of the optical device housing, and is designated by reference numeral 2.
1A indicates a cover. On the other hand, the Kevlar fixing part of the optical input/output component, that is, the sleeve 14, is fitted into a notch formed in the side wall of the support plate (bottom box of the housing) 20 and fixed with a suitable fixture (not shown). be done.

According to this structure, the functional parts of the optical device, that is, the filter 2 and the optical lens system coupling parts of the optical input/output parts 3, 4, and 5, are supported in a so-called floating state with respect to the housing (support plate) 20 and the Kevlar fixing part. Therefore, it is not directly affected by external loads such as vibrations and shocks, or temperature cycles, and has excellent environmental resistance. In this structure, the connecting parts of the Kevlar joint, that is, the ferrule 17 and the sleeve 14, may be made of metal or ceramic.

Furthermore, in both the first and second embodiments described above, the lens 9 of the optical input/output component has a hemispherical shape at one end and a flat surface at the other end; however, the present invention is not limited to this, and for example, It may also be a combination of a spherical lens and a focusing cylindrical lens (self-ox lens).

〔Effect of the invention〕

As described above, according to the present invention, by making the optical lens system coupling part and the Kevlar fixing part of the light input/output component independent from each other, the positional shift of the optical lens system coupling part due to an external load acting on Kevlar can be avoided. It is possible to prevent this and release the stress accumulated in the optical lens system joint.

In addition to the mutual independence of the optical lens system coupling part of the optical input/output component and the Kevlar fixing part, the optical device functional part including the optical functional component and the optical lens system coupling part of the optical input/output component can be placed in a floating state. By installing this, it is possible to achieve high environmental resistance.

[Brief explanation of the drawing]

FIG. 1 is an elevational sectional view of a main part of a first embodiment of an optical demultiplexer according to the present invention. FIG. 2 is an elevational sectional view of the overall configuration of a second embodiment of the optical demultiplexer according to the present invention. FIGS. 3 and 4 are a plan view and an elevational cross-sectional view of a main part of a conventional optical demultiplexer, respectively. 1,1A...Substrate, 2...Filter, 3,4,
5... Optical input/output components, 6... Optical fiber, 7...
Fiber wire, 8,8A...Ferrule, 9...
Lens, 10, 10A...Sleeve, 11...Optical connector, 12...Coating, 13...Kevlar, 1
4... Sleeve, 15, 15A, 16... Support member, 17... Ferrule, 18... Buffer layer, 20
...Support plate (bottom box of case), 21, 21A...Cover.

Claims (1)

[Scope of Claims] 1. An optical functional component, and a pigtail type optical input/output for optical input/output to the optical functional component, which is formed by coupling an optical lens system to one end of an optical fiber and reinforcing the optical fiber with reinforcing fibers. In an optical device comprising a component and a substrate on which the optical functional component and the optical input/output component are mounted, the optical lens system coupling portion to the optical fiber and the reinforcing fiber fixing portion to the optical fiber in the optical input/output component are An optical device characterized in that the optical input/output components are independently fixed to the substrate at the reinforcing fiber fixing section and the optical lens system coupling section. 2. An optical functional component, a pigtail type optical input/output component for optical input/output to the optical functional component, which is formed by coupling an optical lens system to one end of an optical fiber and reinforcing the optical fiber with reinforcing fibers, and the optical function. In an optical device comprising a component and a board on which an optical input/output component is mounted, an optical lens system coupling portion to the optical fiber and a reinforcing fiber fixing portion to the optical fiber in the optical input/output component are independent from each other. Further, the coupling member for coupling the optical lens system to the optical fiber is made of a material substantially equivalent to the optical fiber or the lens, and the optical lens system coupling portion of the optical functional component and the optical input/output component is made of glass or glass. They are fixed to a common substrate made of the same material, and the substrate is mounted on a metal support plate via a buffer layer made of a flexible material, and the reinforcing fiber fixing parts of the optical input/output components are fixed to the metal support plate. An optical device characterized by: