JPH10268158A - Optical demultiplexer and optical coupling component - Google Patents

Abstract

(57) Abstract: A plurality of lights having different wavelengths are separated by reflection of a wavelength filter to reduce a loss of light when entering an optical fiber, thereby simplifying assembly and miniaturizing the apparatus. SOLUTION: A cladding removing part 16 of a first optical fiber 11 is provided.
And the distal end face 20 of the second optical fiber 17
The optical fibers 11 and 17 are arranged such that the angles formed by the respective central axes are acute, and the cut grooves 14 of the first optical fiber 11 are formed.
The wavelength filter 21 is fixedly inserted into the
Light of wavelength λ2 propagated through the first optical fiber 11
The light 24 is reflected and coupled to the distal end face 20 of the second optical fiber 17. With this configuration, the distance between the wavelength filter 21 and the distal end face 20 of the second optical fiber 17 is shortened, the coupling loss of the wavelength-separated light is reduced, and the assembly is facilitated and the size is reduced. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical demultiplexer for transmitting two lights having different wavelengths using one optical fiber, and an optical coupling component having the optical demultiplexer. It is.

[0002]

2. Description of the Related Art In recent years, with the expansion of optical fiber communication networks,
2. Description of the Related Art Communication systems capable of transmitting two or more optical signals having different wavelengths have been introduced.

A conventional optical demultiplexer for mixing or separating two or more light beams having different wavelengths is disclosed in Japanese Patent Publication No. 5-57.
Japanese Patent Application Publication No. 563 (Japanese Patent No. 1851241) is known.

FIG. 8 shows the configuration of a conventional optical demultiplexer that does not use a lens optical system. In FIG.
Reference numerals 2, 3 and 4 denote first, second, third and fourth optical fibers each composed of a core and a clad, as is known.
The first optical fiber 1 and the second optical fiber 2 are provided so that the central axes thereof coincide with each other, and the third optical fiber 3 is formed such that the central axis is perpendicular to the fourth optical fiber 4. Is provided. 5 and 6 are the first optical fibers 1
At the junction of the second optical fiber 2 and the junction of the third optical fiber 3 and the fourth optical fiber 4 are disposed vertically at an angle of 45 degrees with respect to the central axis, respectively. Are first and second wavelength filters for reflecting light of other wavelengths and transmitting light of other wavelengths.

In this configuration, light of different wavelengths λ1, λ2, λ3 propagating in the core of the first optical fiber 1 enters the first wavelength filter 5, and then light of the wavelength λ1 in the first The light having the wavelengths λ 2 and λ 3 is transmitted through the first wavelength filter 5 and enters the core of the second optical fiber 2, and is reflected by the first wavelength filter 5 and enters the adjacent second wavelength filter 6. I do. Of the light that has entered the second wavelength filter 6, the light of wavelength λ2 is reflected by the second wavelength filter 6 and enters the core of the third optical fiber 3, and the light of wavelength λ3 is the second wavelength. The light passes through the filter 6 and enters the core of the fourth optical fiber 4.

As described above, conventionally, an optical demultiplexer that separates a plurality of light beams having different wavelengths propagating in one optical fiber has been configured.

[0007]

However, in the conventional optical demultiplexer shown in FIG. 8, the light which has been confined within the core of the first optical fiber 1 is transmitted to the first wavelength filter. The light is reflected by 5, jumps out of the core, becomes divergent light, crosses the clad portion 7 of the first optical fiber 1 and the clad portion 8 of the third optical fiber 3, and enters the second wavelength filter 6. Therefore, as the distance between the first wavelength filter 5 and the second wavelength filter 6 increases, the degree of divergence of the wavelength-separated light of wavelengths λ2 and λ3 increases, and as a result, the third optical fiber 3 Alternatively, there is a problem that the loss of light that can be coupled into the core of the fourth optical fiber 4 increases.

The present invention has been made to solve the above-mentioned conventional problems, and can greatly reduce the loss of light when reflected by a wavelength filter and incident on an optical fiber. It is an object to provide a detector and an optical coupling component.

[0009]

In order to solve this problem, the present invention removes a part of a clad portion of a first optical fiber, and attaches a distal end face of a second optical fiber to the removed portion. The first optical fiber and the second optical fiber are arranged so that the angles formed by the central axes of the two fibers are acute with each other, and light of a specific wavelength propagated through the first optical fiber is transmitted. An optical demultiplexer is configured by inserting and fixing a wavelength filter in a cut groove formed in the first optical fiber so as to be reflected and coupled to an end face of the second optical fiber.

With this configuration, the light reflected by the wavelength filter hardly passes through the cladding of the first optical fiber and is coupled to the second optical fiber. Can be shortened, and as a result, an excellent optical demultiplexer having a small loss of wavelength-separated light can be obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention has a cutting groove formed obliquely with respect to a central axis, and removes a part of a cladding portion adjacent to the cutting groove. A first optical fiber having a portion formed as described above, and a tip end surface close to a portion formed by removing a part of the clad portion of the first optical fiber, and the first optical fiber has a center axis with respect to a central axis of the first optical fiber. A second optical fiber having a central axis provided obliquely;
A wavelength filter inserted and fixed in the cut groove so as to reflect light of a specific wavelength that has propagated in the first optical fiber and to couple the light to the tip end surface of the second optical fiber. is there. With this configuration, the distance between the wavelength filter and the distal end face of the second optical fiber can be reduced, and as a result, the loss of divergent light that can be coupled into the second optical fiber can be reduced.

According to a second aspect of the present invention, the first optical fiber and the second optical fiber are arranged so that the angle between the respective central axes is an acute angle. With this configuration, the angle between the incident light and the reflected light of the wavelength filter becomes acute, so that the polarization characteristics of the wavelength filter in which the ratio of transmission to reflection changes due to the polarization component of the incident light can be suppressed.

According to a third aspect of the present invention, the tip of the first optical fiber is positioned so that the distal end face of the second optical fiber is close to the surface of the portion of the first optical fiber from which the clad portion has been removed. This is a configuration that is arranged obliquely with respect to the central axis. With this configuration, the distal end surface of the second optical fiber can be in close contact with the side surface of the first optical fiber, so that the distance between the wavelength filter and the distal end surface of the second optical fiber can be further reduced, and the reflection can be reduced. The coupling loss of the diverged light to the second optical fiber can be minimized.

According to a fourth aspect of the present invention, the second optical fiber has a configuration in which the distal end surface is formed in a convex lens shape. With this configuration, since the distal end face of the second optical fiber is sharp, the distance between the second optical fiber and the wavelength filter can be made as short as possible, and the divergent light incident on the distal end face of the second optical fiber is reflected by the convex lens. The light can be collected and efficiently coupled into the second optical fiber.

According to a fifth aspect of the present invention, a spherical lens having a diameter substantially equal to the outer diameter of the second optical fiber is provided between the wavelength filter and the distal end face of the second optical fiber. It is. With this configuration, the divergent light reflected by the wavelength filter can be condensed by the spherical lens and efficiently coupled into the second optical fiber, and the spherical lens can be used without considering the lens optical axis and the like. Since it can be fixed, assembly becomes easy.

According to a sixth aspect of the present invention, there is provided a gradient index lens having an outer diameter substantially equal to the outer diameter of the second optical fiber between the wavelength filter and the distal end face of the second optical fiber. Is provided. With this configuration, the divergent light reflected by the wavelength filter can be condensed by the gradient index lens, and can be efficiently coupled into the second optical fiber. Further, since the outer diameter of the lens is adjusted to the outer diameter of the second optical fiber, the alignment of the optical axis of the lens and the second optical fiber becomes easy, and the lenses can be bonded to each other. Increases productivity.

According to a seventh aspect of the present invention, a groove having a width slightly larger than the outer diameter of each of the first optical fiber and the second optical fiber is provided on a plane, and each of the grooves is provided in each groove. This configuration has a mounting board into which the fiber is inserted and fixed.With this configuration, each optical fiber is inserted and fixed in the groove of the mounting board, so that the optical fiber can be prevented from being misaligned and aligned. Easy and can be firmly fixed.

According to the present invention, a cutting groove into which the wavelength filter is inserted and fixed is integrally formed on a plane of the mounting substrate into which the optical fiber is inserted and fixed so as to correspond to the cutting groove of the first optical fiber. The first configuration is formed by this configuration.
It is easy to process the cut groove formed in the optical fiber, high processing accuracy can be obtained, and the wavelength filter can be firmly fixed.

According to the ninth aspect of the present invention, at least the first
In this optical fiber, the periphery of the portion where the clad portion is removed is filled with a transparent adhesive having a refractive index substantially the same as that of the clad material, whereby the first optical fiber and the second optical fiber Are bonded to each other and the cladding is regenerated, thereby suppressing attenuation of light propagating in the core of the first optical fiber. Since the refractive index can be matched, there is an effect of reducing Fresnel reflection loss.

According to a tenth aspect of the present invention, there is provided an optical coupling component wherein the optical demultiplexer according to the seventh aspect and at least one or more optical functional members are disposed on the same mounting substrate. In addition, with this configuration, a plurality of optical functions can be mounted on a single mounting substrate, so that assembly is easy, productivity is high, and miniaturization of the entire component can be realized.

Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. In the following description, the same reference numerals in the drawings denote members having the same function, and redundant description of the members will be omitted.

FIG. 1 is a configuration diagram of an optical demultiplexer for explaining a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a first optical fiber including a core 12 and a clad 13 as is known, 14 denotes a cutting groove formed to be inclined with respect to the central axis of the first optical fiber 11, and 15 denotes a series. First optical fiber
11 shows one optical fiber formed by separating 11 by a cutting groove 14. Numeral 16 denotes a clad removing portion where a part of the clad 13 adjacent to the cutting groove 14 is removed by grinding or the like.

Reference numeral 17 denotes a second optical fiber comprising a core 18 and a clad 19 as is well known.
The central axis of the optical fiber 17 and the central axis of the first optical fiber 11 are provided so as to be inclined at an acute angle.
It is provided close to 16. Reference numeral 21 denotes a wavelength filter having a characteristic of transmitting the light 23 of the wavelength λ1 and reflecting the light 24 of the wavelength λ2 (λ1 ≠ λ2), and is inserted and fixed in the cut groove 14 of the first optical fiber 11.

In this configuration, the wavelength filter 21 is set so as to be inclined such that the light 22 incident from the first optical fiber 11 is reflected and incident on the second optical fiber 17.
The cutting grooves 14 are also formed to have the same inclination. Therefore, the light 22 that has propagated so as to be confined in the core 12 of the first optical fiber 11 enters the wavelength filter 21 and then
The light 23 having the wavelength λ1 is transmitted through the wavelength filter 21 and enters the optical fiber 15, and the light 24 having the wavelength λ2 is reflected and enters the core 18 of the second optical fiber 17. Functions as a duplexer.

With this configuration, the light 24 of the wavelength λ2 reflected by the wavelength filter 21 and diverged is hardly passed through the clad 13 of the first optical fiber 11, and is coupled to the second optical fiber 17. Therefore, the distance between the wavelength filter 21 and the distal end face 20 of the second optical fiber 17 can be shortened, and as a result, the wavelength λ incident into the core 18 of the second optical fiber 17 can be reduced.
An excellent optical demultiplexer capable of increasing the coupling efficiency of the second light 24 can be obtained.

Further, the first optical fiber is set so that the angle between the light incident on the wavelength filter 21 and the reflected light is acute.
Since the central axes of the optical fiber 11 and the second optical fiber 17 are respectively arranged, an effect is obtained that the polarization characteristic inherent to the wavelength filter in which the ratio of transmission and reflection changes due to the polarization component of the incident light can be suppressed. .

FIG. 2 is a configuration diagram of an optical demultiplexer for explaining a second embodiment of the present invention. In FIG. 2, 25 is the second
The tip end surface of the second optical fiber 17 is formed so as to be inclined with respect to the central axis of the optical fiber 17, and the tip end surface 25 faces the surface of the clad removing portion 16 of the first optical fiber 11. It is configured to be parallel and close.

With this configuration, the tip end face 25 of the second optical fiber 17 can be brought into close contact with the clad removing portion 16 of the first optical fiber 11, so that the wavelength filter 21 and the tip end face of the second optical fiber 17 can be used. The distance between 25 can be further reduced, and the effect of improving the coupling efficiency of the reflected divergent light (light of wavelength λ2) 24 to second optical fiber 17 can be obtained.

FIG. 3 is a configuration diagram of an optical demultiplexer for explaining a third embodiment of the present invention. In FIG. 3, the tip 27 of the second optical fiber 17 is formed in a convex lens shape.

With this configuration, the tip 27 is sharpened, so that the tip 27 is connected to the cladding removing section 16 and the wavelength filter.
It becomes easy to approach the boundary of 21, and the distance between the tip 27 and the wavelength filter 21 can be shortened as much as possible,
The effect is obtained that the divergent light 24 reflected by the wavelength filter 21 is condensed by the convex lens function at the tip 27 and can be efficiently coupled into the second optical fiber 17.

As a method of manufacturing the convex lens shape at the tip 27 of the second optical fiber 17, any suitable processing means and method such as heat melting and grinding may be used.

FIG. 4 is a configuration diagram of an optical demultiplexer for explaining a fourth embodiment of the present invention. In FIG. 4, between the wavelength filter 21 and the distal end face 20 of the second optical fiber 17, the second
An optical demultiplexer is formed by providing a spherical lens 28 having a diameter substantially equal to the outer diameter of the optical fiber 17.

With this configuration, as in the third embodiment, the divergent light 24 reflected by the wavelength filter 21 is transmitted to the spherical lens 28.
And the light can be efficiently coupled into the second optical fiber 17, and since a spherical lens is used, there is no need to consider the optical axis of the lens, and the alignment with the second optical fiber 17 can be performed. Can be adjusted with each other's outer diameter, so that the effect that assembly becomes easy is obtained.

FIG. 5 is a configuration diagram of an optical demultiplexer for explaining a fifth embodiment of the present invention. In FIG. 5, between the wavelength filter 21 and the distal end face 20 of the second optical fiber 17, the second
An optical demultiplexer is provided by providing a gradient index lens 29 having an outer diameter substantially equal to the outer diameter of the optical fiber 17.

With this configuration, similarly to the third embodiment, the divergent light 24 reflected by the wavelength filter 21 is condensed by the gradient index lens 29, and the second optical fiber 17 is efficiently scattered.
Can be combined within. Further, since the outer diameter of the refractive index distribution type lens 29 is made equal to the outer diameter of the second optical fiber 17, the optical axes can be aligned with each other on the outer side, and it is also possible to bond them to each other. Therefore, it is possible to obtain an effect that assembly adjustment is easy and productivity is improved.

If the refractive index distribution type lens 29 has a structure in which the refractive index at the center is high and the refractive index decreases toward the periphery, for example, a graded optical fiber cut to a required size may be used. It may be used as a lens.

FIG. 6 is a configuration diagram of an optical demultiplexer for explaining a sixth embodiment of the present invention and a seventh embodiment described later. The optical demultiplexer according to the sixth embodiment has a configuration in which the outer diameters of the first optical fiber 11, the optical fiber 15, and the second optical fiber 17 are respectively smaller than the outer diameter of the first Grooves 31 and 32 having slightly larger widths are formed, and the first optical fiber 11, the optical fiber 15, and the second optical fiber 17 are inserted and fixed in these grooves 31, 32, respectively, and the optical demultiplexing is performed. It is what constituted the container.

With this configuration, the grooves 31, 32 on the mounting board 30 are formed.
By inserting and fixing the optical fibers 11, 15, 17 into the optical fiber, the optical fibers 11, 15, 17 can be aligned while preventing their misalignment, so that they can be easily assembled and can be firmly fixed. Can be

In the seventh embodiment, as shown in FIG. 6, the mounting substrate 30 is placed on a plane on which the optical fibers are inserted and fixed.
For inserting and fixing the wavelength filter 21, for example, a width of 20 μm
The cutting grooves 33 are formed integrally and simultaneously with the cutting grooves 14 of the first optical fiber 11.

With this configuration, if the cutting groove 33 is machined while the first optical fiber 11 is fixed to the mounting substrate 30, the first
Since the cutting groove 14 can be formed on the optical fiber 11 at the same time, processing is easy, high processing accuracy is obtained in the position and angle of the cutting groove 14, and the wavelength filter 21 is firmly inserted in the cutting groove 33. The effect that it becomes possible to be fixed to is obtained.

Although the mounting substrate 30 is described as being made of a glass member in FIG. 6, the same effect can be obtained even if the mounting substrate 30 is formed using members such as semiconductors, dielectrics, and resins. Needless to say.

According to the eighth embodiment of the present invention, as shown in FIG. 2, the periphery of the clad removing portion 16 of the first optical fiber 11 has substantially the same refractive index as the material forming the clad 13. It is filled with a transparent adhesive 26 having properties.

With this configuration, the transparent adhesive 26 is
The optical fiber 11 and the second optical fiber 17 are bonded and fixed to each other, and the cladding of the cladding removing portion 16 is substantially fixed.
Since this means that the optical fiber 13 has been reproduced, the attenuation of the light propagating in the core of the first optical fiber 11 is suppressed, and the refractive index of the cladding removing part 16 and that of the adjacent second optical fiber 17 are matched. Therefore, the effect of reducing the Fresnel reflection loss of light generated on the distal end face 25 of the second optical fiber 17 can be obtained.

FIG. 7 is a configuration diagram of an optical coupling component having an optical demultiplexer for explaining a ninth embodiment of the present invention. FIG.
In the figure, reference numeral 34 denotes a light emitting element such as a semiconductor laser for causing light of wavelength λ1 to enter the optical fiber 15, and 35 denotes a cut filter inserted and fixed in a cutting groove 36 provided in the middle of the second optical fiber 17. , A wavelength filter that transmits only light of wavelength λ2 and blocks other wavelengths. Reference numeral 37 denotes a light receiving element such as a photodiode for detecting light of wavelength λ2 emitted from the second optical fiber 17.

This optical coupling component is provided with the optical demultiplexer described in the sixth embodiment. The light having the wavelength λ1 emitted from the light emitting element 34 enters the optical fiber 15 and passes through the wavelength filter 21. The light having the wavelength λ2 that has been coupled into the first optical fiber 11 and propagated through the first optical fiber 11 is reflected by the wavelength filter 21 so as to be coupled to the second optical fiber 17 and cut. After the wavelength accuracy of the wavelength λ2 is increased by the filter 35, the filter 35 functions as a wavelength multiplexing light emitting / receiving module that is detected by the light receiving element 37.

With this configuration, the optical demultiplexer described in the sixth embodiment and a plurality of optical functional devices such as the light emitting element 34, the cut filter 35, and the light receiving element 37 are connected to the same mounting substrate 30.
Since the optical module can be mounted on the optical module, it is easy to assemble a module in which a plurality of optical functions are integrated, the productivity is high, and the size can be reduced.

In the optical coupling component shown in FIG.
As an optical functional device other than the optical demultiplexer, the configuration has been described using the light emitting element 34, the wavelength filter 35, and the light receiving element 37.
The optical functional devices mounted on the same mounting board 30 are not limited to those described above.

[0048]

As described above, according to the optical demultiplexer and the optical coupling component of the present invention, the distal end face of the second optical fiber is brought close to the cladding removal portion, and the first optical fiber and the first optical fiber are connected to each other. The first optical fiber is disposed so that the angle formed by the central axis with the second optical fiber becomes an acute angle, and the light having a specific wavelength propagated through the first optical fiber is reflected and coupled to the end face of the second optical fiber. The distance between the wavelength filter and the end face of the second optical fiber can be shortened by forming the optical demultiplexer by inserting and fixing the wavelength filter in the cutting groove of the first optical fiber, and as a result, In addition, the loss of the wavelength-separated light can be reduced.

Further, by forming the distal end face of the second optical fiber obliquely with respect to the center axis so as to approach in parallel with the side face of the clad removing portion, the wavelength filter and the second optical fiber can be provided. The distance between the optical fiber and the distal end surface can be further reduced, and the coupling loss of light incident on the second optical fiber can be minimized.

Further, the distal end face of the second optical fiber is formed in a convex lens shape, or the outer diameter dimension of the second optical fiber is substantially equal to the distance between the wavelength filter and the distal end face of the second optical fiber. By providing a spherical lens having a diameter or a gradient index lens, divergent light incident on the distal end face of the second optical fiber can be collected and efficiently coupled into the second optical fiber.

Also, grooves having widths slightly larger than the outer diameters of the first and second optical fibers are formed on one plane of the mounting substrate of the optical fiber, and the first and second grooves are formed in each groove. By inserting and fixing the second optical fiber, it is possible to prevent misalignment of the optical fibers and to align them, thereby facilitating assembly and firmly fixing.

Further, a cutting groove for inserting and fixing the wavelength filter is integrally formed on the plane of the mounting substrate on which the optical fiber is inserted and fixed so as to correspond to the cutting groove of the first optical fiber. Processing becomes easy, the position of the cutting groove,
High processing accuracy such as angle can be obtained, and the wavelength filter can be firmly fixed.

Further, if the cladding is regenerated by filling the periphery of the cladding removing portion with a transparent adhesive having the same refractive index as the cladding, the first and second optical fibers are bonded and fixed to each other. Thus, effects such as suppressing the attenuation of light propagating in the core of the first optical fiber and reducing the Fresnel reflection loss between the clad portion and the second optical fiber can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an optical demultiplexer for describing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an optical demultiplexer for explaining a second embodiment and an eighth embodiment of the present invention.

FIG. 3 is a configuration diagram of an optical demultiplexer for explaining a third embodiment of the present invention.

FIG. 4 is a configuration diagram of an optical demultiplexer for explaining a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram of an optical demultiplexer for explaining a fifth embodiment of the present invention.

FIG. 6 is a configuration diagram of an optical demultiplexer for explaining a sixth embodiment and a seventh embodiment of the present invention.

FIG. 7 is a configuration diagram for explaining a configuration of an optical coupling component according to a ninth embodiment of the present invention and the present invention.

FIG. 8 is a cross-sectional view illustrating a configuration of a conventional optical demultiplexer.

[Explanation of symbols]

11 ... first optical fiber, 12,18 ... core, 13,19 ... cladding, 14,33,36 ... cutting groove, 15 ... optical fiber,
16: Cladding removing part, 17: Second optical fiber, 20, 25
... the end face of the second optical fiber, 21 ... the wavelength filter,
22 ... light, 23 ... light of wavelength λ1, 24 ... light of wavelength λ2,
26: transparent adhesive, 27 ... tip of the second optical fiber,
28: spherical lens, 29: gradient index lens, 30: mounting board, 31, 32: groove, 34: light emitting element, 35: cut filter, 37: light receiving element.

Claims (10)

[Claims] A first optical fiber having a cutting groove formed obliquely with respect to a central axis and having a portion formed by removing a part of a cladding portion adjacent to the cutting groove; A second optical fiber in which the tip end surface is close to a portion of the first optical fiber obtained by removing a part of the cladding portion, and the central axis of the first optical fiber is provided obliquely with respect to the central axis of the first optical fiber; And a wavelength filter inserted and fixed in the cut groove so as to reflect light of a specific wavelength that has propagated in the first optical fiber and to couple the light to the tip end surface of the second optical fiber. An optical demultiplexer characterized in that: 2. The optical demultiplexer according to claim 1, wherein the first optical fiber and the second optical fiber are arranged so that an angle formed by the respective central axes is an acute angle. 3. The first optical fiber is inclined at an angle with respect to the central axis of the first optical fiber so that the distal end surface of the second optical fiber is close to and parallel to the surface of the portion of the first optical fiber from which the clad portion has been removed. The optical demultiplexer according to claim 1, wherein the optical demultiplexer is arranged. 4. The optical demultiplexer according to claim 1, wherein the second optical fiber has a tip surface formed in a convex lens shape. 5. A spherical lens having a diameter substantially equal to the outer diameter of the second optical fiber is provided between the wavelength filter and the tip end surface of the second optical fiber. An optical demultiplexer as described. 6. A gradient index lens having an outer diameter substantially equal to the outer diameter of the second optical fiber is provided between the wavelength filter and the end face of the second optical fiber. The optical demultiplexer according to claim 1, wherein 7. A mounting wherein a groove having a width slightly larger than the outer diameter of each of the first optical fiber and the second optical fiber is provided on a plane, and the optical fiber is inserted and fixed in each groove. The optical demultiplexer according to claim 1, further comprising a substrate. 8. A cutting groove on which a wavelength filter is inserted and fixed is formed on a plane of the mounting substrate on which an optical fiber is inserted and fixed.
The optical demultiplexer according to claim 7, wherein the optical demultiplexer is integrally formed so as to correspond to the cut groove of the optical fiber. 9. The optical fiber according to claim 1, wherein at least the periphery of the portion of the first optical fiber from which the clad portion is removed is filled with a transparent adhesive having a refractive index substantially equal to that of the clad material. Optical demultiplexer. 10. An optical coupling component, wherein the optical demultiplexer according to claim 7 and at least one or more optical functional members are provided on the same mounting substrate.