JPH0735931A - Optical functional component and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide the structure and manufacture of an optical functional component capable of integrating the optical functional component comprised in transmission line unit. CONSTITUTION:The optical functional component can be comprised by using fiber arrays 4a, 4b on which nXm fibers are arranged at prescribed pitch, and holding one or two or more optical elements 1 between plane lens arrays 2a, 2b on which plane lenses which collimate by converging outgoing light from each fiber are arranged at the terminal parts 3a, 3b of the fiber arrays.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an optical functional component such as an optical filter module, an optical isolator, an optical multiplexing / demultiplexing module and an optical branching / coupling module used in the field of optical communication, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, most optical functional parts such as optical filter modules, optical isolators, optical multiplexing / demultiplexing modules, and optical branching / coupling modules used in the field of optical communication are configured for each transmission line (one fiber unit). The structure is such that a fiber is connected to both ends of an optical element that constitutes each optical functional component.

As the above-mentioned optical elements, there are, for example, filters, beam splitters, polarizing elements, wave plates, etc.
In the case where an optical waveguide is used as an optical functional component, a plurality of optical functional components (one fiber unit) are formed on the same substrate to achieve some degree of integration.

[0004]

As described above, when the conventional optical functional component is used for the optical functional component constituted by one fiber unit, and a large number of complicated optical circuits are constituted in parallel, the optical functional component itself. In addition to the space described above, a storage space for the fiber connecting the optical functional components is required.

Further, in the manufacturing process, the optical axis adjustment process and the like are required for each optical functional component, and the process for connecting the optical functional components is separately required.

Therefore, it is not only difficult to integrate the optical functional parts, which are the conventional transmission lines in units of one fiber, into a high density, but also the number of optical elements used for the integration is high. As the number increases, the cost becomes higher, and there is a problem that it becomes difficult to manufacture the optical functional component.

Further, as described above, it is possible to integrate using an optical waveguide as an optical functional component (constructed on the same substrate), but even in that case, this optical waveguide is constructed in a plane. Therefore, it is difficult to adopt a three-terminal type or a structure having more terminals. For example, in such a structure using an optical waveguide, an optical element having a certain thickness such as a half-wave plate is used. In addition to not being able to
There was a problem such as loss occurring in the connection with the fiber that is the transmission line.

The present invention has been made to solve the above problems, and provides a structure of an optical functional component that enables integration of an optical functional component that is composed of transmission line units, and a manufacturing method thereof. The purpose is to do.

[0009]

The optical functional component according to the present invention uses a fiber array in which n × m fibers are arranged at a predetermined pitch as an optical transmission line, and each fiber is provided at the end of the fiber array. The flat lens array in which the flat lenses (which are arranged corresponding to the respective fibers and coincide with the optical axes of the corresponding fibers) for collimating the light emitted from the light beams are arranged in a fixed manner, It is characterized in that one or more optical elements such as a filter, a beam splitter, a polarizing element, and a wave plate are sandwiched between planar lens arrays.

In particular, when an optical multiplexer / demultiplexer is configured as the optical functional component by using a beam splitter, a wavelength selection filter or the like as the above optical element, each converged light between the first and second planar lens arrays. To the optical axis of
At a position where the optical axis is twice the angle with the normal to the functional surface of the optical element (especially when the angle between the optical axis of the convergent light and the normal to the functional surface is 45 °, these convergence At a position where the angle formed with the optical axis of light is 90 °), the third flat lens array is fixedly arranged on the end face side of the third fiber array.

Further, the optical function component functions as a multiplex transmission / reception module for a larger number of optical transmission lines by combining a plurality of optical elements sandwiched between the first and second planar lens arrays described above. In addition to realizing the parts, it can be realized by an LD array or PD array in which n × m LDs or PDs are arranged at the same pitch as the planar lens array to which n × m LDs or PDs are bonded and fixed, instead of one of these fiber arrays. .

On the other hand, in the method of manufacturing an optical functional component according to the present invention, in particular, the planar lens array, the fiber array, and the respective members of the optical element are fixed.
At least two guide holes for optical alignment are provided in advance in a region outside the lens arrangement region of each planar lens array, and also at the end of each fiber array and the optical element bonded and fixed to each planar lens array. It is characterized in that at least two corresponding guide holes are provided, the guide holes are aligned with each of these members, and then fixed with guide pins.

According to the second manufacturing method, the gradient index rod lens is inserted into and fixed to a member in which guide grooves or holes for positioning at equal intervals are previously processed, and both ends of the fixed member are fixed. By removing the intermediate part of the member so that the distance from the surface becomes a predetermined length (thickness of each flat lens array), the flat lens arrays fixed and opposed to each other are created, and fixed and arranged opposite each other. Each of the one or more optical elements inserted in the space where the member is removed is adhered and fixed to each of the planar lens arrays.

[0014]

The optical functional component according to the present invention is adhesively fixed to the end portion of the fiber array composed of n × m fibers, and one or more or more are disposed between the flat lens arrays fixed and opposed to each other. Since it is configured by sandwiching optical elements, it is possible to have multiple optical functions at the same time, and it is possible to integrate n × m cores, which is required (optical function) × (number of required fiber cores). ) Compared with the conventional case in which a plurality of optical functional parts (fiber core unit) are connected and housed via a fiber, the size (integration) can be greatly reduced.

Further, the optical functional component configured as described above uses an optical element such as a beam splitter for emitting the incident signal light in a direction perpendicular to the optical axis, a wavelength selection filter, and the like. It is possible to take out the reflected light reflected by the functional surface of (1) by using an n × m fiber array (a plane lens array is fixedly adhered to the end portion) arranged at the same pitch.

On the other hand, in the method of manufacturing an optical functional component according to the present invention, each member is provided with a guide hole for optical alignment in advance, and is adhered and fixed collectively by a guide pin (first manufacturing method). Alternatively, the flat lens array is prepared in a fixed state in advance, and each member is bonded and fixed with the flat lens array as a reference (second manufacturing method).
By keeping the array pitch accuracy of each array (fiber array and planar lens array) at or above a predetermined accuracy, it is possible to perform collective alignment (match the optical axes) and simplify the manufacturing process. To do.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the figure, the same parts are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 shows a first optical functional component according to the present invention.
FIG. 6 is a diagram showing a configuration according to an embodiment of the present invention, in which the optical functional component is a fiber array in which n × m fibers are arranged at equal intervals, and the optical axes of the respective fibers are aligned and face each other. First and second fiber arrays 4a,
First and second flat lenses, which are fixedly arranged so as to face each other at the respective end portions 3a and 3b of 4b, and which collimate the light emitted from each fiber in parallel, are arranged at the same pitch as the arrangement pitch of each fiber. The second planar lens arrays 2a, 2b are fixed by adhesion, and further, as the optical element 1 between the first and second planar lens arrays 2a, 2b, for example, a filter, a beam splitter, a polarizing element,
It is configured by sandwiching a wave plate or the like.

In particular, in the first and second fiber arrays 4a and 4b, as shown in FIG. 2, an 8-core tape fiber 6 is V-grooved at the same 250 μm pitch as the 8-core tape fiber 6. Adhesively fixed to the V-grooved member 5 (FIG. (A)), and further, four layers were laminated while preventing the V-grooved members 5 from being displaced by the guide pins 7, and then the whole was adhesively fixed (see FIG. b)), and finally, the end face portion is polished and manufactured.

Further, with respect to the first and second planar lens arrays 2a and 2b, the V-groove processing member 5 is provided with the GI optical fiber in the same manner as in the case of manufacturing the first and second fiber arrays 4a and 4b. After adhering and fixing, and stacking four pieces, both end faces have a thickness of 1.18 mm or 2.36.
It is manufactured by polishing so that the thickness becomes mm.

On the other hand, a general manufacturing method of the above-mentioned optical functional component is generally composed of 8 × 4 fibers by vertically stacking four layers of fixed 8-core connectors and fixing them. First and second fiber arrays 4a, 4
b, and then the first and second planar lens arrays 2a, 2b polished by the method described above to a thickness of 1.18 mm, and the ends 3a of the first and second fiber arrays. 3b is bonded and fixed by aligning the optical axes of the respective fibers to form a lens-equipped fiber array.

Thereafter, in order to obtain a predetermined structure, the alignment is fixed while monitoring each member using light of a wavelength used.

As a method for simplifying the aligning work as described above, a corresponding guide hole for pre-fixing each member to be adhesively fixed is provided, and the members are collectively fixed with a guide pin. Does the above alignment work become unnecessary?
Manufacturing method) or in the state where the first and second flat lens arrays 2a and 2b are fixed in advance, and each member is based on the fixed first and second flat lens arrays 2a and 2b. There is also a method of adhesively fixing (second manufacturing method).

Next, a second embodiment of the present invention will be described with reference to FIGS. 3 and 4. In this embodiment, as the optical element sandwiched between the first and second planar lens arrays 2a and 2b, a three-terminal optical functional component for multiplexing and demultiplexing two kinds of optical signals by using the beam splitter 9a will be described. To do.

Usually, as shown in FIG. 3, the optical element 1 sandwiched between the first and second plane lens arrays 2a and 2b has the first and second plane lens arrays 2a and 2b.
When fixedly arranged at an angle A (0 ° to 90 °) formed with the normal line 1c of the functional surface 1b with respect to the optical axis 8a of each converged light between b, a part of the incident optical signal is The convergent light is reflected in a direction forming an angle 2A with respect to the optical axis 8a.

Therefore, when a boom splitter, a wavelength selection filter or the like is used as the optical element 1,
A third fiber array 4c having an optical axis perpendicular to the optical axis 8a of the converged light (the end portion 3c of the third fiber array is bonded and fixed to the third planar lens array 2c) By providing the optical functional component (multiplexer / demultiplexer) as shown in FIG.

As a concrete example, according to the optical functional component according to the second embodiment, the beam splitter 9a which transmits the light of 1.30 μm as the optical element 1 and reflects the light of 1.55 μm by the functional surface 1a thereof. Is used, the optical signal of 1.30 μm incident from the first fiber array 4a is bonded to the end portion 3a of the first flat lens array 2 by adhesion.
The light signal of 1.55 μm which becomes the convergent light at a, is transmitted through the beam splitter 9a, and is incident from the third fiber array 4c is converged at the third flat lens array 2c that is adhesively fixed to the end portion 3c. And the beam splitter 9a
By being reflected by the functional surface 1a of the above, the combined light obtained by combining these two kinds of optical signals is condensed by the second planar lens array 2b which is arranged opposite to the second planar lens array 2b, and from the end 3b of the second planar lens array 2b. It is emitted to the fiber array 4b.

On the other hand, the combined signal of 1.30 μm and 1.55 μm incident from the second fiber array 4b receives the end 3
The second plane lens array 2b fixed to b converts the light into convergent light, which is 1.55 μm on the functional surface 1a of the beam splitter 9a.
Only the optical signal of m is reflected, and the optical signal of 1.30 μm is condensed by the first plane lens array 2a and emitted to the first fiber array 4a. Further, the optical signal of 1.55 μm is condensed by the third plane lens array 2c and emitted to the third fiber array 4c.

Next, as a third embodiment of the present invention, an optical functional component (three terminals) in which, for example, two beam splitters 9a, 9b are sandwiched between the first preliminary second planar lens arrays 2a, 2b. The multiplexer / demultiplexer will be described with reference to FIG.

In this embodiment, the first and second beam splitters 9a and 9b are bonded and fixed by sandwiching the plane lens array 2e, and the first beam splitter 9 is also fixed.
The light a that transmits 1.30 μm light and reflects the light 1.55 μm is used as a, and the second beam splitter 9b transmits the light 1.30 μm and 1.55 μm and then 1.65.
The one that reflects light of μm is used.

When the above three types of optical signals are multiplexed, the first
The optical signal of 1.30 μm incident from the fiber array 4a becomes convergent light at the first plane lens array adhered and fixed to the end portion 3a and passes through the first beam splitter 9a, while the fourth fiber array 4d Incident from 1.5
The optical signal of 5 μm is converged by the fourth planar lens array 2d fixed to the end 3d and reflected by the functional surface 1a of the first beam splitter 9a.
The combined light of 0 μm and 1.55 μm is used for the plane lens array 2
It is condensed by e and becomes convergent light again and is incident on the second beam splitter 9b.

Then, this second beam splitter 9b
The combined light of 1.30 μm and 1.55 μm incident on is transmitted through the second beam splitter 9b as it is,
An optical signal of 1.65 μm incident from the third fiber array 4c becomes convergent light at the third plane lens array 2c that is adhesively fixed to the end portion 3c, and finally 1.30 μm of these.
The combined lights of m, 1.55 μm, and 1.65 μm are condensed by the second plane lens array 2b and then emitted from the second fiber array 4b.

On the contrary, in the case of demultiplexing each of the three types of multiplexed optical signals, the combined light incident from the second fiber array 4b is fixed by the second flat lens array 2b at the end 3b. It becomes convergent light, and the second beam splitter 9
Only the optical signal of 1.65 μm is reflected by the functional surface 1a of b, is condensed by the third plane lens array 2b, and is emitted from the third fiber array 4b.

Further, this second beam splitter 9b
The combined light that has passed through is condensed by the plane lens array 2e and emitted again as converged light to the first beam splitter 9a, and an optical signal of 1.30 μm is transmitted through this first beam splitter 9a, After being condensed by the lens array 2a and emitted from the first fiber array 4a, an optical signal of 1.55 μm is emitted from the first beam splitter 9a.
The fourth plane lens array 2 is reflected by the functional surface 1a of a.
After being collected at d, it is emitted from the fourth fiber array 4d.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

In FIG. 6, the wavelengths of 1.31 μm and 1.
A configuration example for realizing a function of multiplexing / demultiplexing test light (wavelength 1.65 μm) for testing an abnormality of the optical cable 11 in a bidirectional wavelength-multiplexed optical communication system using two 55 μm optical signals is shown. It is a figure.

For convenience of explanation, the configuration will be described with a plan view, but each member is configured in a matrix as described above, and the wavelength selection filter 10 is used as an optical functional component.
a, 10b, 10c are used.

Usually, on the upstream side of the two-way wavelength division multiplexing optical communication system (for convenience of explanation, the right side of the drawing is the down direction, and the left side of the drawing is the up direction), the first fiber array 4 is used.
The down signal light having a wavelength of 1.31 μm incident from a is converted into converged light by the first planar lens array 2a that is adhesively fixed to the end portion 3a, and the first wavelength selection filter 10a
After passing through (a wavelength selection filter that transmits an optical signal of 1.31 μm and reflects an optical signal of 1.55 μm), it is condensed by the planar lens array 2e and is again converged light.
The light is emitted to the optical cable 11 via the plane lens array 2b and the end 3b.

Thereafter, on the downstream side, the 1.31 μm optical signal propagating through the optical cable 11 is reflected through the end 304, the plane lens arrays 204 and 293, and the wavelength selection filter 10c (1.31 μm optical signal is reflected, 1.55μ
The light is reflected by a functional surface of a wavelength selection filter (which transmits an optical signal of m), is condensed by the plane lens array 201, and is then emitted as converged light from the end portion 301 to the fiber array 401 again.

On the other hand, from the downstream side, the fiber array 402
The upstream optical signal of 1.55 μm emitted from the end 30
The light is converted into convergent light by the plane lens array 202 that is fixedly bonded to the second lens 2, passes through the wavelength selection filter 10c, is condensed by the plane lens arrays 203 and 204, and is again emitted as converged light to the optical cable 11 via the end 304. .

After that, on the upstream side, the function of the first wavelength selection filter 10a of the 1.55 μm optical signal propagating through the optical cable 11 is passed through the end 3b, the second planar lens array 2b and the planar lens array 2e. Is reflected on the surface,
After being condensed by the fourth planar lens array 2d, it is again emitted as converged light from the end 3d to the fourth fiber array 4d.

As described above, in the bidirectional wavelength division multiplexing optical communication system, bidirectional optical communication is performed using optical signals of different wavelengths. The optical cable 11 in this system is used.
In the case of performing the test of 1, the configuration is shown as A in the figure. This has the same configuration as that of FIG. 5 described above, and the description of the bidirectional wavelength division multiplexing optical communication system has also been made corresponding to the names of the components of FIG.

In FIG. 6, 10b is 1.31.
Transmitting optical signals of μm and 1.55 μm, 1.65 μm
Is a wavelength selection filter that reflects the optical signal of 1., and is installed between the planar lens array 2e and the second planar lens array 2b in order to extract the optical signal of 1.65 μm as the test light.

Therefore, this wavelength selection filter 10b
The optical signal (1.65 μm) reflected by the functional surface of the
After being condensed by the plane lens array 2c of 1, the light is again extracted as converged light through the filter 12. Then, only the outgoing light of the transmission path (fiber forming the optical cable) to be tested is selected by the core selection switch 13, and the failure is judged in the line testing unit 14 based on the waveform of the selected outgoing light.

The above-mentioned test means may be installed at the position B in the figure, and the line test can be performed with the configuration shown in FIG. 5 as in the case described above. From these facts, according to the present invention, it is possible to arrange a larger number of optical functional components in series and without interposing a fiber. Therefore, the optical functional components arranged in the optical path (in this embodiment, the wavelength selection filter) are used. ), It becomes possible to combine and demultiplex the test light of wavelength 1.65 μm for testing the abnormality of the fiber which is the transmission path.

Further, in the above embodiment, the already configured system is provided with means for performing a test so that the terminal part has the configuration shown in FIG. 5. However, the configuration of A in FIG. For example, as shown in FIG. 7, an LD (laser diode) array 15 may be used in place of the first fiber array 4a, and a PD (photodiode) array 16 may be used in place of the third fiber array 4d. With such a configuration, a part of the system can be realized as a single test terminal portion, and the same effect can be obtained without changing the configuration of other terminal portions.

On the other hand, in the wavelength selection filters 10a, 10b and 10c described in the above embodiment (FIG. 6), the optical axis 8a of the signal light incident on the prism as shown in FIG. 8 and the normal line 1b thereof are arranged. A dielectric multilayer film (functional surface 1a) having an angle of 30 ° is used, and the angle between the optical axis 8b of the reflected signal light and the optical axis 8a is designed to be 60 °. , 0.34 μm Si as a dielectric multilayer film
It was configured by alternately laminating 100 layers of O ₂ and 0.29 μm Al ₂ O ₃ .

[0048]

As described above, according to the present invention, the configuration that conventionally requires a plurality of optical functional components is integrated into a configuration by configuring a plurality of fibers that are transmission lines on an array. In addition, since it is possible to bond and fix multiple types of optical functional components without using a fiber, it is possible to obtain an optical functional component that is very easily and compactly integrated as compared with conventional products. effective.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an optical functional component according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the structure of a fiber array that constitutes the optical functional component according to the present invention.

FIG. 3 is a diagram for explaining a fixed position of an optical element that constitutes the optical functional component according to the present invention.

FIG. 4 is a diagram showing the configuration of a two-signal optical multiplexer / demultiplexer according to a second embodiment of the optical functional component according to the present invention.

FIG. 5 is a diagram showing a configuration of a three-signal optical multiplexer / demultiplexer according to a third embodiment of the optical functional component according to the present invention.

FIG. 6 is a diagram showing an application example applied to a two-way multiplex optical communication system as a fourth embodiment of the optical functional component according to the present invention.

FIG. 7 is a diagram showing a configuration of an optical transceiver module according to a fifth embodiment of the optical functional component according to the present invention.

FIG. 8 is a diagram showing a configuration of a wavelength selection filter as an optical element constituting the optical functional component according to the present invention.

[Explanation of symbols]

1 ... Optical element, 2a, 2b, 2c, 2d, 2e, 20
1, 202, 203, 204 ... Planar lens array, 3
a, 3b, 3c, 3d, 301, 302, 304 ... Fiber array end portions 4a, 4b, 4c, 4d, 401, 4
02 ... Fiber array, 5 ... V groove processing member, 6 ... Tape fiber, 7 ... Guide pin, 9a, 9b ... Beam splitter, 10a, 10b, 10c ... Wavelength selection filter, 1
1 ... Optical cable, 12 ... Filter, 13 ... Core selection switch, 14 ... Line test, 15 ... LD array, 16 ... PD
array.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Toru Yamanishi Toru Yamanishi 1 Taya-cho, Sakae-ku, Yokohama, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Tadatoshi Tanito 1-6 Uchiyuki-cho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (7)

[Claims] 1. A fiber array in which n × m fibers are arranged at equal intervals, and first and second fiber arrays arranged so as to face each other with their optical axes coincident with each other, A flat lens is fixedly arranged so that the first and second fiber arrays face each other at opposite ends, and a flat lens that collimates the light emitted from each fiber in parallel is arranged at the same pitch as the array pitch of each fiber. An optical functional component comprising: first and second planar lens arrays that are arranged; and one or more optical elements sandwiched between the first and second planar lens arrays that are arranged to face each other. 2. A fiber array in which n × m fibers are arranged at equal intervals, and first and second fiber arrays arranged so as to face each other so that the optical axes of the respective fibers coincide with each other. A flat lens is fixedly arranged so that the first and second fiber arrays face each other at opposite ends, and a flat lens that collimates the light emitted from each fiber in parallel is arranged at the same pitch as the array pitch of each fiber. Arrayed first and second planar lens arrays, an optical element fixedly arranged at a predetermined angle with respect to an optical axis of each convergent light between the first and second planar lens arrays, and the optical element The third planar lens array is fixed to the optical axis of each of the convergent lights at a position where the optical axis is twice the angle formed by the normal to the functional surface of the optical element. Fixed on the end side Optical functional component having a arranged a third fiber array. 3. The optical element is fixedly arranged at a position where an angle formed by the normal line of the functional surface of the optical element of the convergent light between the first and second planar lens arrays is 45 °. Further, the third fiber array having the third planar lens array fixedly arranged on the end side thereof is fixedly arranged at a position where an angle formed by the optical axis of the converged light and the optical axis is 90 °. The optical functional component according to claim 2, wherein the optical functional component is provided. 4. It is sandwiched between the first and second planar lens arrays and is fixedly arranged at a position where an angle with the optical axis of the convergent light and a normal line of its functional surface is a predetermined angle. The optical functional component according to claim 2, wherein a plurality of the optical elements are arranged. 5. An n × m number of LDs or PDs instead of either the first or second fiber array.
5. The optical functional component according to claim 1, further comprising an LD array or a PD array arranged at the same pitch as that of the first or second planar lens array. 6. An end portion of each fiber array which is provided with at least two guide holes for optical alignment in advance in an area outside the lens arrangement area of each planar lens array, and which is adhesively fixed to each planar lens array. And at least two guide holes corresponding to the optical element are provided, and after matching the guide holes provided in advance to the respective members,
Manufacturing method of optical functional parts fixed with guide pins. 7. A gradient index rod lens is inserted into a member in which guide grooves or holes for aligning at regular intervals are machined, and is fixed, and a distance from both end faces of the fixed member is predetermined. By removing an intermediate portion of the member so as to have a length, a flat lens array fixedly opposed to each other is created, and between the flat lens arrays fixedly opposed to each other, the member is A method of manufacturing an optical functional component, wherein one or more optical elements are inserted into the removed space and adhesively fixed to each of the planar lens arrays.