JPH08190026A - Optical transmitting and receiving module - Google Patents

Abstract

PURPOSE: To provide an inexpensive and compact optical transmitting/receiving. CONSTITUTION: This module is a planar optical waveguide circuit type optical transmitting/receiving module for transmitting an optical signal of wavelength 1.55μm through and transmitting/receiving an optical signal of wavelength 1.3μm. A dielectric multilayer film filter 5 is mounted perpendicular to the reference plane of a planar optical waveguide circuit and a single-mode optical waveguide is composed of a first input/output optical waveguide 2 whose one end is connected to a first optical fiber connecting part and a second input/output optical waveguide 3 whose one end is connected to a second optical fiber connecting part and the other end is branched from the first input/output optical waveguide 2 with a branching angle 15 deg.-25 deg. on or in the vicinity of the front surface of the dielectric multilayer film filter 5, the first input/output optical waveguide 2 is Y-branched on the side where the second input/output optical waveguide 3 does not exist in reference to the dielectric multilayer film filter 5 and a laser diode 7 or a photodiode 8 is connected to each branched optical waveguide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical component for optical communication, and more particularly to a module for transmitting and receiving optical signals as an optical terminal for optical subscribers (for each home). is there.

[0002]

2. Description of the Related Art Recently, construction of an optical fiber network in each home has been seriously studied in order to significantly reduce the cost of large-capacity communication such as video signals and personal computer data. One of the biggest problems faced there is the price of the optical transceiver module placed in each home. Conventionally, optical communication has been used in offices and the like that communicate large-capacity signals. In such applications, there was a demand even if the price of the optical transceiver module was on the order of 1 million yen, but if the optical transceiver module is placed in each home, it will not be widely spread unless the price drops to the order of 10,000 yen. I can't expect. Against this background, low-priced optical transceiver modules to be placed in each home are being actively developed.

The conventional optical transmission / reception module mainly uses a micro optical component such as a lens. In that case, most of the cost was in the alignment process of each component.
Therefore, the present inventors have achieved a planar lightwave circuit (PlanarLightwaveCir) with a reduced number of parts.
We have been working on the development of an optical transceiver module using a CUT (PLC). FIG. 16 shows the optical transceiver module manufactured so far. See "Optical Mod" for details
ule with a Silica-Based P
lanar Lightwave Circuit fo
r Fiber-Optic Subscriber
Systems ", H. Teruiet al., IE
EE Photon. Technol. Lett. , V
ol. 4, 1992, pp. 660-662. Here, its configuration and principle will be briefly described.

An input side single mode optical fiber 10A and an output side single mode optical fiber 10B are fixed to the planar lightwave circuit 1 via glass blocks 9A and 9B, respectively. More specifically, the optical fiber 10
A and 10B are inserted and fixed in the grooves provided in the glass block, and the glass blocks 9A and 9B are the optical fibers 10.
The optical axes of A and 10B are bonded and fixed to the planar lightwave circuit 1 so that the optical axes of A and 10B coincide with the optical axes of the optical waveguides 24 and 25.
The light incident from the input port 24A is transmitted through the Mach-Zehnder interferometer type wavelength multiplexer / demultiplexer using the two directional couplers 24B and 24C, and the 1.3 μm band light is transmitted to the through port.
Light in the 1.55 μm band is output to the cross port. The 1.55 μm band light output to the cross port is directly coupled to the single mode optical fiber 10B at the waveguide end and output to the outside. On the other hand, the 1.3 μm band light output to the through port of the wavelength multiplexer / demultiplexer is divided into two by the Y branch 6 and coupled to the laser diode 7 and the photodiode 8, respectively. The laser diode 7 is provided for transmitting a transmission signal from the receiver side, and the photodiode 8 is provided for converting a received optical signal into an electric signal.

The light in the 1.55 μm band is used for distributing a multi-channel video signal from a telephone station to a general home, for example, and the light in the 1.3 μm band is used for bidirectional communication of various data signals. used. Therefore, the 1.55 μm band receiving module becomes expensive because it receives a large capacity signal. The optical transmission / reception module currently aimed at is capable of transmitting and receiving various data signals first, so an expensive 1.55 μm band optical receiver is put out to
We aim at a low-cost module that can send and receive only relatively low-speed optical signals in the m band. It should be added that since 1.55 μm light transmits a large capacity signal, a single mode optical fiber must be used when it is output from the optical transceiver module. Further, for the optical signal in the 1.3 μm band, since the ping-pong method in which the upstream and the downstream are separated in time is adopted, the restriction on the near-end reflection is loose.

[0006]

As described above, we have developed an optical transceiver module using a PLC as a low-cost optical terminal for each home. Therefore, the biggest problems are the size of the module and the cost of connecting the optical fiber and the PLC. In the configuration of FIG. 16, the input optical fiber 10A for 1.3 μm and 1.55 μm and the output optical fiber 10B for 1.55 μm are PLCs.
Since they are arranged on the end faces facing each other, the size of the module as a whole becomes large. Further, there is a problem that the optical fiber and the PLC have to be connected twice.

[0007]

Therefore, in the present invention, in order to reduce the size of the optical transmission / reception module, the two input / output fibers are arranged on the same end face rather than the opposite end faces. Therefore, the PLC wavelength multiplexer / demultiplexer is configured to transmit light of 1.3 μm and reflect light of 1.55 μm. Specifically, a dielectric multilayer filter is inserted into the waveguide at an angle, 1.3 μm light is transmitted through the filter, and 1.55 μm light is reflected by the filter to separate light of two wavelengths.

Conventionally, it has been reported that a wavelength multiplexer / demultiplexer using reflection of a dielectric multilayer filter uses a fiber or a waveguide. For example, "Filter-Embedde
dDesign and Its Applicati
ons to Passive Component
S., "H. Yanakagawa et al., J. Li.
ghwave Technology. , Vol. 7,198
9, pp. 1646-1653. However, most of them receive the reflected light in a multi-mode optical fiber or a multi-mode optical waveguide, and there is almost no reported example of coupling the reflected light to a single-mode optical waveguide as in the present invention. . The reason is that it was very difficult to couple the light reflected by the dielectric multilayer filter by the single mode optical waveguide.
The present invention seeks experimentally optimum conditions for how to efficiently couple light reflected by a filter into a single-mode optical waveguide, and for an adhesive that is compatible with mounting of a laser diode or a photodiode. It is a thing.

That is, the optical transceiver module according to the present invention is an optical transceiver module that transmits an optical signal having a wavelength of 1.55 μm and transmits and receives an optical signal having a wavelength of 1.3 μm, and includes a single mode optical waveguide, a laser diode,
A planar optical waveguide circuit type having a photodiode and a dielectric multilayer filter, and first and second optical fiber connecting portions, wherein the dielectric multilayer filter is installed substantially perpendicular to a reference plane of the planar optical waveguide circuit. , The single mode optical waveguide has a first end connected to the first optical fiber connection portion.
Of the input / output optical waveguide, one end of which is connected to the second optical fiber connecting portion and the other end of which is the surface of the dielectric multilayer filter or within 8 μm from the surface, and the branch angle with the normal line of the dielectric multilayer filter as the center line. A second input / output optical waveguide branching from the first input / output optical waveguide at 15 ° to 25 °;
The input / output optical waveguide is characterized by Y-branching on the side where the second input / output optical waveguide is absent with respect to the dielectric multilayer filter, and a laser diode or a photodiode is connected to each of the branched optical waveguides.

The first and second optical fiber connecting portions may be integrated as a two-core optical fiber array connecting portion.

A groove may be provided on the surface of the planar optical waveguide circuit, and the dielectric multilayer filter may be fixed to the groove with a silicone adhesive.

There may be a gap of 1 μm to 5 μm between the two input / output optical waveguides at the intersection of the first input / output optical waveguide and the second input / output optical waveguide.

A marker for processing the groove may be provided on the surface of the planar waveguide circuit at a position apart from the installation position of the groove.

The width of the first input / output optical waveguide and the width of the second input / output optical waveguide may be larger than the widths of other portions in the vicinity of the mutual branch points, and the Y branch portion is a dielectric. It may be on the body multilayer filter.

A dielectric multi-layer film filter for blocking light having a wavelength of 1.3 μm may be inserted in the second input / output optical waveguide.

[0016]

In the optical transceiver module of the present invention, since the input and output optical fibers are arranged on the same end face of the PLC, the overall size is reduced and the PLC and the optical fiber are connected only once. You can finish with. As a result, it is possible to realize an optical transceiver module that is lower cost and more compact than conventional ones.

[0017]

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

Example 1 In this example, a silica-based planar lightwave circuit (PLC) produced by depositing silica-based glass on a silicon substrate, a two-core optical fiber array in which two optical fibers are paired, and output. An optical transceiver module was fabricated by combining a laser diode and a waveguide type photodiode designed so that the mode field at the end face matches the mode field of a single mode optical fiber. A silica-based planar lightwave circuit is fabricated on a silicon substrate by flame deposition and reactive ion etching, and has realized an optical waveguide circuit with low loss and good compatibility with a single-mode optical fiber. For more information,
Masao Kawauchi "Planar Lightwave Circuits" Electron Theory C, Volume 113, 6
No., 1993. The optical connection between the PLC and laser diode or photodiode is P
It was performed using Silicon Terrace which is an LC substrate. For details, see Y. Yamada et al. , Electro
n. Lett. , Vol. 29, 444, 1993.

The circuit configuration of the PLC 30 of this embodiment is shown in FIG. Also, an enlarged cross-sectional view of AA 'in FIG. 1 is shown in FIG.
3 is an enlarged cross-sectional view of FIG.

Cores 2, 3 and 2'are formed on a silicon substrate 11 so as to be covered with a clad 12 to form single mode optical waveguides 2, 3 and 2 '. The relative refractive index difference between the core and the clad is 0.75%, and the core size is 7μ
It is m square. A groove 4 is provided near the intersection of the optical waveguides 2 and 3, and a dielectric multilayer film 5 is inserted therein,
It is fixed with an adhesive 13. The optical axis of the optical waveguide 2'formed on the opposite side of the dielectric multilayer film 5 from the optical waveguides 2 and 3 coincides with the optical axis of the optical waveguide 2, and the optical waveguide 2'is a part of the optical waveguide 2. It is a part.

An input single-mode optical fiber 10A and an output optical fiber 10B are connected to the planar lightwave circuit 3 by a glass block 9B for fixing, with their optical axes aligned with the optical waveguides 2 and 3, respectively. The distance between the input / output ports 2A and 3A was 250 μm.

Wavelength-multiplexed light of 1.3 μm and 1.55 μm from the optical fiber 10A enters the first input / output optical waveguide 2 from the first input / output port 2A,
The light of 5 μm is reflected by the dielectric multilayer film filter 5 and the second
Input / output optical waveguide 3 to single mode optical fiber 10
Output to B. The light of 1.3 μm passes through the dielectric multilayer filter 5, is divided into two by the Y branch 6 as in the conventional case of FIG. 16, and is then coupled to the laser diode 7 and the photodiode 8, respectively.

The dielectric multilayer filter 5 is designed so that light of 1.3 μm is transmitted and light of 1.55 μm is reflected. In reality, SiO ₂ and TiO ₂ were alternately vapor-deposited in multiple layers on a polyimide thin film having a thickness of 7 μm to have a thickness of 9 μm, and the entire filter had a thickness of 16 μm. On the other hand, the groove for inserting the filter was processed by a dicing saw, and the groove width was 18 μm and the groove depth was 200 μm. Here, the groove width is set to 18 μm in order to make the gap small in order to stand the filter having a thickness of 16 μm as perpendicular to the substrate as possible. When using a filter having a thickness of 16 μm, a groove width of 17 μm to 20 μm is suitable. Also, regarding the depth of the groove, if the depth is shallow, the filter is likely to incline. Therefore, the depth is preferably deep if possible. However, if the groove is deepened, the entrance of the groove tends to be widened due to processing, so the groove depth is preferably 100 μm to 300 μm.

In this embodiment, after dicing and processing the groove on the market, a filter was inserted and fixed with a silicone adhesive. The reason why the silicone adhesive, which has a weaker adhesive strength of about two orders of magnitude than the epoxy adhesive for fixing the filter, is intentionally used here is as follows. In the optical transceiver module according to the present embodiment, the laser diode and the photodiode are fixed by AuSn solder after mounting the filter, so that the temperature needs to be raised to about 300 ° C. At this time, the epoxy adhesive changes in quality and a large shrinkage occurs. Then, peeling of the adhesive occurs in the groove. As a result, reflection increases and the standard as the optical transceiver module is not satisfied. Compared with this, the adhesive strength of the silicone-based adhesive is weak, but 30
Since no change occurs at a temperature of about 0 ° C, peeling of the adhesive does not occur. Originally, fixing to the groove of the filter is a part where no external force is applied, so strength may be weak. Therefore, in this embodiment, a silicone adhesive is used to fix the filter. A groove was actually processed perpendicularly to the linear waveguide, and the above-mentioned dielectric multilayer filters were fixed with an epoxy adhesive and a silicone adhesive, respectively. It was measured before and after heat treatment at 10 ° C. for 10 minutes. The results are shown in Table 1. The reflection of silicone-based adhesive does not change by heat treatment, while the reflection of the epoxy-based adhesive is greatly increased. The reason for this is that the epoxy-based adhesive contracted at a high temperature of 300 ° C. as described above.

[0025]

[Table 1]

The waveguide design near the filter insertion portion was experimentally determined because there are uncertain factors. FIG. 4 shows an enlarged view around the filter insertion portion. Here, a slit 17 having a width of 2 μm was provided between the first input / output optical waveguide 2 and the second input / output optical waveguide 3. This is to prevent air bubbles from being generated or rough glass portions to be generated in the forked portions of the two optical waveguides 2 and 3 in the step of filling the core with the upper clad glass after patterning the core. If the slits 17 were not actually provided, air bubbles could occur in the forked portions of the two optical waveguides. The probability was more remarkable when the crossing angle θ between the two waveguides 2 and 3 was as small as about 10 °. This time, by providing a slit with a width of 2 μm, an escape path for bubbles was created, and the upper clad glass could be filled up to a narrow gap cleanly. The width of the gap 17 is preferably 1 to 5 μm, which is a region larger than the resolution of the mask when processing the core glass and in which the optical loss can be almost ignored.

Next, the crossing angle θ of the two input / output optical waveguides 2 and 3 and the groove 4 into which the dielectric multilayer filter 5 is inserted.
For the position of, the optimum value was experimentally obtained. 1.55 μm transmitted from I / O port 2A to I / O port 3A
FIG. 5 is a graph in which the vertical axis represents the light loss of the above and the horizontal axis represents the distance x between the intersection of the center lines 14 and 15 of the two input / output optical waveguides 2 and 3 and the center line 16 of the groove 4. . Here, the crossing angle θ between the two input / output optical waveguides 2 and 3 was set to 20 °. It is understood from this graph that the distance x between the intersection of the center lines 14 and 15 of the two input / output optical waveguides and the center line of the groove is optimally in the range of 4 ± 4 μm. Since the position of the center line 16 of the groove 4 changes depending on the thickness of the filter 5 and the width of the groove 4, the intersection of the center lines of the two input / output optical waveguides and the surface of the filter. -4 ± 4μm if converted to distance
(0 to -8 μm). In this embodiment, this value was used to process the filter insertion groove.

As can be seen from FIG. 5, the position of the groove is 1.5.
It greatly affects the loss of light of 5 μm. Therefore, in order to process the position of the groove with good reproducibility, the marker of the groove was formed by depositing a metal thin film on the surface of the upper clad glass in this example. The reason why the marker is created using the metal thin film is that it is easier to see than the case where the marker is created using the core glass. Since the step of forming the metal thin film is also used for the electric wiring of the laser diode or the photodiode, it is not necessary to increase the process step by performing both of them at the same time.
I would like to emphasize here that when a marker made of a metal thin film is on the waveguide surface, if that part is processed with a dicing saw, the metal adheres to the inner wall of the processed groove, or the metal becomes a tooth of the dicing saw. By clogging between
The problem is that the processing accuracy deteriorates. Therefore, in order to solve these problems, in this embodiment, a marker made of a metal thin film was formed at a position displaced by -50 μm from the center line of the groove. Since a commercially available dicing saw has a function of moving the cutting position with high accuracy, alignment is performed with a marker made of a metal thin film, and then 50
The groove was processed by moving the μm cutting position. FIG. 6 shows a diagram including the marker 18. In this example, Au was used as the marker thin metal film.

Crossing angle θ of the two input / output optical waveguides 2 and 3
With respect to, the crossing angle θ is changed to 1.
The loss of 55 μm light was determined experimentally. FIG. 7 shows the results. The larger the crossing angle θ, the larger the excessive loss due to the positional deviation of the groove. From this result, it is found that it is effective to reduce the crossing angle θ in order to loosen the tolerance of the groove position against the processing error. FIG. 8 shows a graph in which the vertical axis represents the positional deviation amount and the horizontal axis represents the crossing angle θ at which the excessive loss due to the positional deviation of the groove becomes 0.5 dB. Considering that the machining position accuracy of the groove of the dicing saw is about 3 μm, it is understood that the crossing angle θ is preferably 25 ° or less. Further, FIG. 9 shows a graph in which the vertical axis represents the return loss of 1.55 μm light at the first input / output port 2A and the horizontal axis represents the crossing angle θ. From this graph, the crossing angle θ
It can be seen that the value of the return loss increases with increasing. When an analog signal is used for 1.55 μm light, the return loss is required to be 30 dB or more. Therefore, the crossing angle θ is preferably 15 ° or more. that's all,
2 from the viewpoint of filter insertion groove position accuracy and return loss
The intersection angle θ of the book input / output optical waveguides 2 and 3 is 15 ° to 25
° is suitable.

The first input / output port 2 for 1.55 μm light of the optical transmitter-receiver module of the present embodiment thus created
The insertion loss from A to the second input / output port 3A was 1.5 dB including the connection loss with the single mode fiber. The return loss at that time was 38 dB. The insertion loss from the first input / output port 2A to the photodiode 8 was 3.8 dB including the principle loss of 3 dB due to the Y branch 6.

Example 2 As described in Example 1, the excessive loss of 1.55 μm light strongly depends on the positional accuracy of the filter insertion groove. In order to loosen the positional accuracy, the width of the waveguide is widened near the waveguide intersection in this embodiment. An enlarged view of the intersection is shown in FIG. 2B, 3B and 2'B are optical waveguides 2, 3 respectively.
And 2'widened portions. The width of the waveguide was 7 μm at a place other than the intersection, and the width was gradually changed immediately before the intersection, and was 6 μm to 12 μm at the intersection. The horizontal axis represents the width of the waveguide at the intersection, and the vertical axis represents the tolerance of the positional deviation of the filter 5 when the insertion loss of 1.55 μm light increases by 0.5 dB. FIG. 11 shows the calculation result obtained by changing this at the intersection angle θ = 10 ° to 40 °. Obviously, widening the width of the waveguide at the intersection weakens the tolerance of the filter for positional deviation. In an actual waveguide, if the waveguide width is made too wide, higher-order modes tend to stand up, so the waveguide width at the intersection is 10 μm.
m to 15 μm is suitable.

Embodiment 3 Since the optical transmitter / receiver module of the present invention is intended for low cost, it is also necessary to make the required PLC size as small as possible and to increase the number of modules that can be produced from one PLC wafer. . Therefore, in this embodiment, the intersection of the two input / output optical waveguides described in the second embodiment and the Y branch located at the subsequent stage are integrated. The whole figure is shown in FIG.
FIG. 13 shows an enlarged view of the intersection. As shown by 2B and 3B, the widths of the first and second input / output optical waveguides 2 and 3 are widened by the taper before the intersection. Thereafter, the 1.3 μm light passes through the filter 5 and is branched into the two optical waveguides 21A and 21B of the Y branch 21. By adopting this configuration, it is possible to integrate the Y-branch, which is conventionally created independently after the wavelength multiplexer / demultiplexer, with the wavelength multiplexer / demultiplexer. As a result, the area of the PLC can be reduced.
Specifically, when the intersection and the Y branch as the wavelength multiplexer / demultiplexer are independently arranged, the size of the PLC is 3 mm × 20 mm, but by integrating them, 3 mm ×
It could be reduced to 15 mm. This makes one PLC
The number of modules that can be created from has increased 1.3 times.

Fourth Embodiment In the circuit configuration of the first embodiment, the 1.55 μm light is completely reflected by the dielectric multilayer film filter 5 and hardly leaks into the photodiode 8 for receiving 1.3 μm light.
The actually produced result was -50 dB of crosstalk. On the other hand, the amount of 1.3 μm light leaking into the second input / output optical waveguide 3 is considerably large. In the actually created circuit, the maximum leakage light of about -20 dB was observed. This is an imperfection of the dielectric multilayer filter 5, but it is essentially difficult to reduce this value. Therefore, in this embodiment, a dielectric multilayer filter that cuts light of 1.3 μm is inserted in a part of the second input / output optical waveguide. Two types of filter insertion methods were created. One of them is shown in Figure 14.
FIG. 15 shows the other. In FIG. 14, the groove 4B was processed by using a dicing saw similarly to the crossing portion. At this time, the filter 21 for cutting 1.3 μm light is made to cross only the second input / output optical waveguide 3 so as not to cross the first input / output optical waveguide 2. Although the groove 4A crosses the first input / output optical waveguide 2, an adhesive is filled in the groove, and the loss for that is small.

On the other hand, in the embodiment of FIG. 15, the groove 4C for the 1.3 μm light cut filter 22 is processed by etching. In this case, it is not necessary to form an unnecessary groove in the first input / output optical waveguide 2. In both cases of FIG. 14 and FIG. 15, the 1.3 μm crosstalk output from the second input / output optical waveguide is −2 when the cut filter is not inserted.
It was possible to significantly reduce it from 0 dB to -45 dB.

In the configuration of FIGS. 14 and 15, FIG.
Of course, it is also possible to integrate the Y branches, as shown in FIG.

Although the embodiments of the present invention have been described with respect to the case where the silica-based waveguide is used, the circuit of the present invention is a diffusion glass waveguide other than the silica-based waveguide, a polymer waveguide, and an L waveguide.
It can be applied to any waveguide such as iNbO ₃ waveguide.

In the present invention, 1.3 μm light is transmitted and received,
Although the description has been made with respect to the optical transmission / reception module that transmits 1.55 μm light, by replacing the dielectric multilayer filters shown in the embodiments, an optical transmission module in other wavelength regions or an optical wavelength multiplexer / demultiplexer can be used. Obviously it could be used.

[0038]

As described above, the optical transmission / reception module of the present invention is low in price and compact, and thus can be widely used as a home optical terminal.

[Brief description of drawings]

FIG. 1 is a schematic plan view of an optical transceiver module as a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line AA ′ of FIG.

FIG. 3 is an enlarged sectional view taken along line BB ′ of FIG.

FIG. 4 is an enlarged view of the vicinity of a filter insertion portion of the first embodiment.

FIG. 5 is a tolerance curve of the insertion loss of 1.55 μm light with respect to the filter groove, where the vertical axis represents the loss of 1.55 μm light and the horizontal axis represents the intersection of the center lines of the two input / output optical waveguides and the filter groove. It is a graph as a distance from the center line.

FIG. 6 is an enlarged view of the vicinity of a filter insertion portion including a marker for processing a filter groove.

FIG. 7 is a graph showing the tolerance of a 1.55 μm optical insertion loss with respect to a filter groove when the crossing angle θ of two input / output optical waveguides is changed.

FIG. 8 is a graph showing a tolerance amount by which the excess loss of 1.55 μm light is increased by 0.5 dB when the crossing angle θ of two input / output optical waveguides is changed.

FIG. 9 is a graph showing the return loss of 1.55 μm light when the crossing angle θ of two input / output optical waveguides is changed.

FIG. 10 is an enlarged sectional view of the vicinity of a filter insertion portion of the second embodiment.

FIG. 11 is a graph showing changes in the amount of tolerance of filter positional deviation when the waveguide width is widened at the intersection of two input / output optical waveguides.

FIG. 12 is a schematic plan view showing an overall view of a third embodiment.

FIG. 13 is an enlarged view of the vicinity of the filter insertion portion of FIG.

FIG. 14 is an overall view of a fourth embodiment.

FIG. 15 is an overall view of another configuration example of the fourth embodiment.

FIG. 16 is a plan view showing a conventional optical transceiver module.

[Explanation of symbols]

1 Conventional silica-based planar lightwave circuit (PLC) 2 First input / output optical waveguide 3 Second input / output optical waveguide 4, 4B, 4C Dielectric multilayer filter insertion groove 5 1.3 μm Transmits light 1. 55 μm Dielectric multilayer filter that reflects light 6,21 Y-branch 7 Laser diode 8 Photodiode 9A, 9B, 9C Optical fiber fixing glass block 10A, 10B Single mode optical fiber 11 Silicon substrate 12 Clad glass 13 Dielectric multilayer film Adhesive for fixing filter 14 Center line of first input optical waveguide 15 Center line of second input optical waveguide 16 Center line of groove for inserting dielectric multilayer filter 17 First input / output optical waveguide and second input Slit 18 at a portion in contact with the output optical waveguide 18 Au marker for groove processing 22 Dielectric that reflects 1.3 μm light and transmits 1.55 μm light Silica-based planar lightwave circuit according to layer film filter 30 the invention

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fenguta Suzuki 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corp. No. Japan Telegraph and Telephone Corporation

Claims (8)

[Claims] 1. An optical transceiver module which transmits an optical signal having a wavelength of 1.55 μm and transmits and receives an optical signal having a wavelength of 1.3 μm, which comprises a single mode optical waveguide, a laser diode, a photodiode and a dielectric multilayer filter. , First and second
Is a planar optical waveguide circuit type having an optical fiber connection portion, the dielectric multilayer filter is installed substantially perpendicular to a reference plane of the planar optical waveguide circuit, the single mode optical waveguide, one end is the first A first input / output optical waveguide connected to the first optical fiber connection portion, one end connected to the second optical fiber connection portion, and the other end being 8 μm from the surface of the dielectric multilayer filter.
Within the point, the first input / output optical waveguide is branched from the first input / output optical waveguide at a branch angle of 15 ° to 25 ° with the normal line of the dielectric multilayer filter as the center line. Of the input / output optical waveguide is Y-branched on the side where the second input / output optical waveguide is absent with respect to the dielectric multilayer film filter, and the laser diode or the photodiode is connected to each of the branched optical waveguides. A featured optical transceiver module. 2. The optical transceiver module according to claim 1, wherein the first and second optical fiber connecting portions are integrated as a two-core optical fiber array connecting portion. 3. A groove is provided on the surface of the planar optical waveguide circuit, and the dielectric multilayer filter is fixed to the groove with a silicone-based adhesive. The optical transceiver module described in. 4. A gap of 1 μm to 5 μm is provided between the two input / output optical waveguides at the intersection of the first input / output optical waveguide and the second input / output optical waveguide. The optical transceiver module according to any one of claims 1 to 3. 5. A marker for processing the groove is provided on the surface of the planar waveguide circuit at a position apart from the installation position of the groove. An optical transceiver module according to item 1. 6. The width of the first input / output optical waveguide and the width of the second input / output optical waveguide are wider in the vicinity of mutual branch points than in other portions. The optical transceiver module according to any one of claims 1 to 5. 7. The optical transceiver module according to claim 1, wherein the Y branch portion is on a dielectric multilayer filter. 8. The second input / output optical waveguide has a wavelength of 1.3.
8. The optical transceiver module according to claim 1, further comprising a dielectric multi-layer film filter that blocks μm light.