JP2000009953A - Wavelength demultiplexer and optical transmission and reception module having the demultiplexer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength demultiplexer, and an optical transmission and reception module, on which a light receiving device is easily mounted, whose cost is reduced and in which the loss of signal light beams is suppressed. SOLUTION: An optical transmission and reception module 2 is provided with a wavelength demultiplexer 1 and a transmission module 3. The demultiplexer 1 is provided with a first substrate member 10, an optical fiber 11, a filter and a first PD 6a. The member 10 is provided with a flat first reference surface 13 and a V groove 14. A mirror-shaped film is formed on the inner surface of the groove 14. An optical fiber 11 is arranged in the groove 14. The filter is inserted into the member 10 in the condition that the fiber 11 is mechanically separated. The filter is arranged orthogonally to the surface 13 when looking from the top of the demultiplexer 1 and along the direction crossing an optical axis P of the fiber 11 when looking from the top of the demultiplexer 1. The PD 6a is provided on the top of the filter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength demultiplexer as an optical device used for, for example, optical communication, and an optical transceiver module having the optical demultiplexer.

[0002]

2. Description of the Related Art For example, an optical transmission / reception module 51 having a wavelength demultiplexer as an optical device used in optical communication and the like disclosed in Japanese Patent Application Laid-Open No. Hei 8-190026 is shown in FIG.
As shown in the figure, a planar optical waveguide 52 (Planer Lightwave C)
ircuit) and a laser diode (Laser Diod) as a light emitting device disposed at a predetermined position of the planar optical waveguide 52.
e: hereinafter referred to as LD) 53 and a pair of photodiodes (Photodiode: hereinafter referred to as PD) as a light receiving device
54 a and 54 b and a filter 55 are provided.

[0003] The planar optical waveguide 52 is formed on a substrate material 56 made of silicon single crystal, and has a core 57 and a clad 58 made of SiO ₂ or the like and having different refractive indexes.

When the core 57 and the clad 58 are formed, an FHD method (Flame Hydrolisys Deposition: flame deposition method) or a CVD method (Chemical Vapor Deposition method) is used.
ition: Chemical vapor deposition method or PVD method (Physic
al Vapor Deposition).

The pair of PDs 54a and 54b are
Each is a built-in waveguide type photodiode having an optical waveguide optically connected to the core 57 of the planar optical waveguide 52.

[0006]

The above-described FH for forming the planar optical waveguide 52 of the optical transceiver module 51 described above.
The time required for performing a film forming method such as the D method, the CVD method, or the PVD method tends to be long. In addition, relatively expensive equipment is required for performing the film forming method and performing dry etching for forming the waveguide (core 57) pattern.

[0007] Further, as the light receiving device, photodiodes 54a and 5 of a built-in waveguide type having a built-in optical waveguide.
4b, the core 57 of the planar optical waveguide 52 and the waveguide built-in PDs 54a and 54b need to maintain a high degree of deviation from the optical axis of each other.
In addition to the optical axis adjustment described above, the operation time for performing the optical axis adjustment of the PDs 54a and 54b tends to be long. Further, the photodiodes 54a and 54b with a built-in waveguide tend to have a high unit price because of the built-in optical waveguide. For this reason, the optical transmission / reception module 51 tends to be difficult to mount and costly.

Further, the wavelength demultiplexer 61 constituting an optical transmitting / receiving module having a surface light receiving type photodiode (surface light receiving type PD) which is lower in cost than the above-described waveguide built-in type photodiodes 54a and 54b. As a light receiving structure of an optical signal, there is known a structure having a structure shown in FIG. 9 shown in Japanese Patent Application Laid-Open No. H03-36508.

The wavelength demultiplexer 61 illustrated in FIG. 9 has a core 6 formed on a substrate material 62 made of silicon single crystal.
3, a planar optical waveguide 65 having a cladding 64 and a core 66, a filter 66 that divides the core 63 and is inserted into the planar optical waveguide 65, and a surface light receiving type PD 67 provided on the planar optical waveguide 65; It has. Surface light receiving type PD6
7 has a light receiving surface 67a formed with a predetermined area (spread).

The signal light receiving structure of the wavelength demultiplexer 61 is such that the signal light having a predetermined wavelength of the signal light transmitted through the core 63 is reflected by the filter 66 and received by the surface light receiving type PD 67. It leads to the surface 67a. The wavelength demultiplexer 61 has an insertion groove 68 for inserting the filter 66 along a direction inclined with respect to the flat surface of the planar optical waveguide 65.

For this reason, it is necessary to grind the blade of a dicing machine or the like while obliquely tilting the blade.
During the grinding process, the blade is shaken or the like, so that the processing becomes difficult and the optical waveguide is unintentionally damaged.
It is difficult to form the end face of the substrate into a mirror surface. For this reason, the loss when transmitting the signal light tends to increase.

As a method of detecting a split signal light from a waveguide by using a surface light receiving type PD, Japanese Patent Laid-Open No.
10 (A) and 10 shown in JP-A-8905
Structures 71a and 71b for receiving signal light guided in the core 73 as shown in FIG. FIG. 10 (A)
And light receiving structures 71a and 71b illustrated in FIG.
Comprises an optical waveguide 74 having a core 73 formed on a substrate material 72 made of silicon single crystal;
There are provided reflecting members 75a and 75b, which are provided opposite to the end face 73a of the core 73 and are formed in a minute size, and surface light receiving PDs 76a and 76b, respectively.

The reflecting member 75a of the light receiving structure 71a shown in FIG. 10A has a reflecting surface 77a that faces the end face 73a of the core 73 and reflects signal light. The reflection surface 77a is formed so as to be gradually inclined away from the end surface 73a of the core 73 as it goes upward. The surface light receiving type PD 76a has a light receiving surface 78a for receiving signal light. The surface light receiving type PD 76a is provided above the reflecting member 75a with the light receiving surface 78a facing the substrate material 72 and the reflecting surface 77a.

The reflecting member 75b of the light receiving structure 71b shown in FIG. 10B has a reflecting surface 77b facing the end face 73a of the core 73. The reflection surface 77b gradually moves toward the end surface 73a of the core 73 as it goes downward.
It is formed so as to be inclined in a direction away from it. The surface light receiving type PD 76b has a light receiving surface 78b for receiving signal light. The surface light receiving type PD 76b is buried in the substrate member 72 with the light receiving surface 78b facing the reflection surface 77b.

The light receiving structures 71a and 71b having the above-described structure are used.
Reflects the signal light emitted from the end face 73a of the core 73 by the reflection surfaces 77a and 77b of the reflection members 75a and 75b, and receives the signal light by the light reception surfaces 78a and 78b of the surface light receiving type PDs 76a and 76b. ing.

However, the aforementioned small-sized reflecting members 75a and 75b are used to transmit signal light to the surface-receiving PDs 76a and 76b.
It is difficult to mount at a predetermined position leading to b. Also,
In the light receiving structure 71a shown in FIG. 10A, the surface light receiving type PD 76a is supported in a cantilevered state by the reflection member 75a, so that there are problems in wiring method and strength, and
In the light receiving structure 71b shown in FIG. 10B, since the lower surface of the reflecting member 75b is smaller than the upper surface, the reflecting member
5b and the like tend to be difficult to position, and mounting tends to be more difficult.

Accordingly, it is an object of the present invention to provide a low-cost, easy-to-install package without using a surface-receiving type PD and without using a reflection member, and to suppress a loss when transmitting signal light. SUMMARY OF THE INVENTION It is an object of the present invention to provide a transmitting / receiving module provided with a wave filter and the wavelength demultiplexer.

[0018]

According to a first aspect of the present invention, there is provided a wavelength demultiplexer according to the first aspect, wherein a light receiving device is arranged at a predetermined position and is formed flat.
A first substrate member having a reference surface and a V-groove formed concavely from the first reference surface; an optical fiber disposed in the V-groove; A filter that reflects the signal light having the wavelength and transmits the signal light having the second wavelength transmitted through the optical fiber, cuts the optical fiber, and is inserted into the substrate member, and is reflected by the filter. And a light guide section for guiding the signal light having the first wavelength to the light receiving device.

According to a second aspect of the present invention, there is provided a wavelength demultiplexer.
Wherein the light receiving device is disposed above the filter and the light guide.

According to a third aspect of the present invention, there is provided a wavelength demultiplexer.
Alternatively, in the wavelength demultiplexer according to claim 2, the light receiving device is a surface light receiving type photodiode.

According to a fourth aspect of the present invention, there is provided a wavelength demultiplexer according to the first aspect.
4. The wavelength demultiplexer according to claim 3, wherein the light guide includes a mirror-like film formed at least near the filter on the inner surface of the V-groove. 5. Features.

According to a fifth aspect of the present invention, there is provided a wavelength demultiplexer according to the first aspect.
5. The wavelength demultiplexer according to claim 4, wherein the filter is provided by being inserted into the substrate member along a direction perpendicular to a first reference plane of the substrate member. 6. It is characterized by having been.

The wavelength demultiplexer according to the sixth aspect is the first aspect.
6. The wavelength demultiplexer according to claim 5, wherein the optical fiber is formed flat and overlaps the first reference surface across the V groove. 7. The lid member is attached to the substrate member by a lid member having:

[0024] The optical transceiver module according to claim 7 is
A first substrate member having a V groove in which an optical fiber is provided and a flat first reference surface along the optical fiber in which a light receiving device is provided in a predetermined position; A filter that is inserted into the substrate member and reflects the signal light having the first wavelength transmitted through the optical fiber and transmits the signal light having the second wavelength transmitted through the optical fiber; A first light device including: a light guide section for guiding the signal light having the first wavelength to the light receiving device; a V-groove for disposing the optical fiber; and emitting the signal light to the optical fiber. And a second optical device having a light emitting device.

In the wavelength demultiplexer according to the first aspect, signal light is transmitted using an optical fiber disposed in a V-groove of a substrate member.
For this reason, it is not necessary to form an optical waveguide by a film forming method or the like, as compared with a case where signal light is transmitted using an optical waveguide having a core and a clad. Become. In addition, since an optical fiber generally having a lower loss than that of the optical waveguide is used, it is possible to suppress a loss when transmitting the signal light.

In the wavelength demultiplexer according to the second and third aspects, since the light receiving device is a photodiode of a surface light receiving type, the positioning accuracy of the light receiving device and the use of a filter inserted into a substrate member are provided. Requirements for the accuracy of the insertion groove and the like used for the above can be relaxed.

In the wavelength demultiplexer according to the fourth aspect, the light guide for guiding the signal light reflected by the filter to the light receiving device is a film made of a mirror-like metal formed on the inner surface of the V-groove. By providing a light receiving device above the light guide, the signal light reflected on the mirror-like metal film can be reliably guided to the light receiving device.
At this time, the signal light reflected from the metal film spreads somewhat and reaches the light receiving device. However, if the light receiving area of the light receiving device is sufficiently secured in advance, the signal light can be reliably detected even if the mounting of the light receiving device is slightly shifted. . Therefore, the light receiving device can be mounted without increasing the mounting accuracy, and the signal light can be easily detected.

In the wavelength demultiplexer according to the fifth aspect, since the filter is inserted into the substrate member along a direction perpendicular to the first reference plane, the filter is formed when the filter is inserted. The insertion groove to be formed can be easily formed. Since the blade of the dicing machine used at this time grinds perpendicularly to the first reference plane, blurring and the like are suppressed, so that damage to the optical fiber is suppressed. Therefore, loss at the time of transmitting the signal light can be suppressed.

In the wavelength demultiplexer according to the sixth aspect, since the optical fiber is attached to the first substrate member by the lid member, it is possible to prevent the optical fiber from being displaced after being attached. Therefore, the light receiving device can more reliably receive the signal light, and the loss of the signal light received by the light receiving device can be suppressed.

According to a seventh aspect of the present invention, in the transmitting / receiving module, the first optical device on which the light receiving device is provided is a V-shaped substrate member.
Signal light is transmitted using an optical fiber arranged in the groove. For this reason, it is not necessary to form the optical waveguide by a film forming method or the like as compared with a case where signal light is transmitted using an optical waveguide having a core and a clad, and thus cost reduction can be achieved. . In addition, since an optical fiber generally having a lower loss than that of the optical waveguide is used, it is possible to suppress a loss when transmitting the signal light.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. Wavelength demultiplexer (Wavelength-Divis) shown in FIG.
The ion multiplexing 1 is an optical device used for the optical transmitting and receiving module 2 shown in FIG.

The optical transmitting / receiving module 2 is provided at a predetermined position with a first photodiode (Photodiod) as a light receiving device.
e: hereinafter referred to as PD) The wavelength demultiplexer 1 as a first optical device on which a 6a is disposed, a laser diode (Laser Diode: hereinafter referred to as LD) 5 as a light emitting device at a predetermined position, and a light receiving device as a light receiving device A transmission module 3 as a second optical device having a second photodiode (hereinafter, referred to as PD) 6b is provided.
The wavelength demultiplexer 1 is a receiving module.

As shown in FIGS. 1 to 4, the wavelength demultiplexer 1 includes a first substrate member 10, an optical fiber 11, a filter 12 (shown in FIG. 4), and the above-described first PD 6a. ,
It has. The first substrate member 10 is made of a substrate material made of quartz glass, silicon single crystal, or the like.
Reference surface 13 and a V-groove 14 are provided.

The first reference surface 13 is made of a surface of a substrate material constituting the first substrate member 10 and is formed flat. The first reference surface 13 is configured to arrange the first PD 6a at a predetermined position. In FIG. 1, the first reference plane 13 is located on the upper side.

The V groove 14 is formed so as to be concave from the first reference surface 13, and has a V-shaped cross section so that the opening gradually narrows as the distance from the first reference surface 13 increases. Is formed. The V-groove 14 is formed from one end face 15 of the first substrate member 10 to the other end face 16 located on the opposite side of the end face 15.

When the substrate material of the first substrate member 10 is made of silicon single crystal, the V-groove 14 can be formed by anisotropic etching, grinding, or the like. When it is made of quartz glass, it can be formed by grinding or the like.

In the illustrated example, the first substrate member 10
Is made of silicon single crystal in which the above-mentioned first reference plane 13 is the (100) plane. Further, as shown in FIG. 2, the V-groove 14 is formed by anisotropic etching using a KOH solution or the like, and its inner surfaces 17 and 1 are formed.
7 and the first reference plane 13 form an angle θ of 54.7 degrees.

A first electrode portion 18 is formed on the first reference surface 13 of the first substrate member 10. The first electrode portion 18 is provided at a position on the first reference surface 13 where the first electrode portion 18 is electrically connected to the first PD 6a. The first electrode unit 18 is electrically connected to an external device or the like, and outputs the reception status of the PD 6a to the external device or the like.

The optical fiber 11 is connected to the first substrate member 1.
The first substrate member 10 is provided so as to protrude from end surfaces 15 and 16 of the first substrate member 10. The optical fiber 11 is configured such that an optical connector or the like that optically connects to an external optical fiber or the like is connected to one end 11 a protruding from the one end face 15, and that the other end protrudes from the other end face 16. The LD 5 of the transmission module 3 is optically connected to the end 11b.

The optical fiber 11 is connected to the first substrate member 1.
The lid member 19 is attached to the first substrate member 10 by a lid member 19 separate from the first substrate member. Lid member 19
Has a second reference surface 19a which is formed flat and overlaps the first reference surface 13. Lid member 19
Extends across the V-groove 14 and the second reference surface 19a
The optical fiber 11 is sandwiched and fixed between the inner surfaces 17, 17 of the V-groove 14 and the second reference surface 19a in a state where the optical fiber 11 is superimposed on the first reference surface 13.

In the illustrated example, the lid member 19 is
One end 1 of the first substrate member 10 on one end surface 15 side
0a and the other end 10b located on the other end face 16 side.
, Respectively. Also, the lid member 19
Is attached to the first substrate member 10, the bonding means 19 such as a UV curing material or solder which cures when irradiated with ultraviolet rays.
b (shown in FIG. 4) is used.

The filter 12 is formed in a plate shape.
Of the signal light having a wavelength of 1.3 μm and the signal light of 1.55 μm mainly used in optical communication, the signal light of one wavelength transmitted by the LD 5 is transmitted and the signal light of the other wavelength is reflected. To prevent transmission.

In the illustrated example, the LD 5 has a wavelength of 1.3 μm.
m signal light is transmitted. For this reason, the filter 12 transmits the signal light having the wavelength of 1.3 μm as the second wavelength and reflects the signal light having the wavelength of 1.55 μm as the first wavelength.

The filter 12 is inserted into the first substrate member 10 in a state where the optical fiber 11 disposed in the V-groove 14 is mechanically divided. The filter 1
2 is a first reference plane 1 viewed from the side of the wavelength demultiplexer 1.
The optical axis is inserted into the first substrate member 10 along a direction perpendicular to the optical fiber 11 and is a signal light transmission direction of the optical fiber 11 as viewed from above the wavelength demultiplexer 1 (one point in the drawing). Along the direction intersecting the direction indicated by the chain line P)
It is inserted into the first substrate member 10.

In the illustrated example, the angle between the filter 12 and the signal light transmission direction of the optical fiber 11 indicated by a dashed line P in FIG.
It is inserted into the first substrate member 10 in a predetermined state.

The filter 12 is inserted into an insertion groove 7 formed by a dicing machine or the like along a direction substantially perpendicular to the first reference plane 13 and crossing the optical axis P. Later, by UV curing agent, etc.
It is adapted to be fixed to the first substrate member 10.

A mirror-like film 20 made of a metal such as gold or chromium is formed on the inner surfaces 17, 17 of the V-groove 14, at least near the filter 12. The film 20 made of such a metal is formed on the inner surfaces 17, 17 of the V-groove 14 by vapor deposition or the like.

The film 20 reflects the signal light having a wavelength of 1.55 μm as the first wavelength reflected by the filter 12 above the V-groove 14 along the arrow H1 in FIG. ing. In the illustrated example, the metal film 20 is formed on the inner surfaces 17 over the entire length of the V groove 14. The film 20 constitutes the light guide section described in this specification.

The first PD 6a is provided above the metal film 20 and the filter 12 as the light guide. The PD 6a is connected to the first reference surface 13
Is attached and fixed by an adhesive means 23 such as a UV curing agent or solder. The PD 6a is connected to the first
Are electrically connected by soldering to the electrode portions 18 of the first and second electrodes.

As shown in FIG. 2, the PD 6a has, on a surface facing the film 20 and the filter 12, a light receiving window 21 for transmitting the signal light having a wavelength of 1.55 μm and a light passing through the light receiving window 21. And a light receiving surface 22 having a predetermined area (spread) for receiving the signal light.

With the above-described configuration, the filter 12
And the wavelength reflected by the film 20 made of metal is 1.
The 55 μm signal light passes through the light receiving window 21 and is received by the light receiving surface 22 along arrows H1 and H2 in FIG.

In the illustrated example, the light-receiving surface 22 is formed in a circular shape having a diameter of 80 μm, and the light-receiving window 21 has a diameter of 1 mm arranged concentrically with the light-receiving surface 22.
It has a circular shape of 00 μm and a reflectivity of 6.3%. The distance D between the light receiving window 21 and the light receiving surface 22
1 is formed to 200 μm, and the reflectance of the film 20 made of metal as the light guide is formed to 98%.

At this time, the first reference plane 13
FIG. 5 shows the light receiving ratio of the signal light having a wavelength of 1.55 μm with respect to the distance L between the optical axis P of the optical fiber 11 and the center O of the light receiving surface 22 along. According to FIG. 5, the distance L between the optical axis P of the optical fiber 11 and the center O of the light receiving surface 22 along the first reference surface 13 is 13 μm.
Even if the value is relatively large from m to 45 μm, the light receiving rate of the light receiving surface 22 can be maintained at 80% or more.

As shown in FIGS. 6 and 7, the transmission module 3 is provided with a second substrate member 30 and the LD 5 described above.
And a second PD 6b. The second substrate member 30 is made of a substrate material made of quartz glass, silicon single crystal, or the like, and has a flat reference surface 31, a V groove 32,
A fiber abutment groove 33 and an LD alignment mark (not shown) are provided.

The reference surface 31 is connected to the second substrate member 3.
The LD 5 and the PD 6 b are formed at a predetermined position, and are made of a surface of a substrate material constituting the O.sub.0. In FIG. 7, the reference plane 31 is located on the upper side.

The V-shaped groove 32 is formed so as to be concave from the reference surface 31, and has a V-shaped cross section so that the opening gradually narrows as the distance from the reference surface 31 increases. The V-groove 32 extends from one end surface 34 of the second substrate member 31 to an intermediate portion of the substrate member 31.

The V-shaped groove 32 is provided in the second substrate member 30.
When the substrate material is composed of silicon single crystal,
It can be formed by anisotropic etching or grinding, and when the substrate material is made of quartz glass, it can be formed by grinding.

The fiber abutment groove 33 is formed so as to be concave from the reference surface 31, extends in a direction intersecting the V-shaped groove 32, and extends on both side edges 30 of the second substrate member 30.
a and 30b. The fiber abutment groove 33 and the V groove 32 communicate with each other. The fiber abutment groove 33 is formed by grinding or the like.

The reference surface 3 of the second substrate member 30
1 is provided with a second electrode portion 35. This second
Of the LD5, PD6 on the reference surface 31
It is provided at a position to be electrically connected to b. The second electrode unit 35 is electrically connected to an external device or the like, and transmits a signal light from the LD 5 according to a signal light transmission start command input through the external device or the like.
The reception status of the PD 6b at the time of transmitting the LD5 is output to the external device or the like.

The LD 5 is attached to a predetermined position of the reference surface 31 optically connected to the optical fiber 11 of the wavelength demultiplexer 1 disposed in the V groove 32 by a UV curing agent, solder, or the like. Is fixed. LD5
Are soldered to the second electrode portion 35 and are electrically connected.

The LD 5 transmits a signal light having a wavelength of 1.3 μm as a second wavelength to the optical fiber 11 of the wavelength demultiplexer 1 disposed in the V groove 32.
At the same time as the transmission of the signal light, the monitor signal light is transmitted to the second PD 6b.

Further, the LD 5 allows the optical fiber 1 on the reference surface 31 to be moved by the LD alignment mark.
1 and is easily positioned at a position optically connected to each other.

The PD 6b is attached to and fixed to a predetermined position of the reference surface 31 adjacent to the LD 5 and capable of receiving the monitoring signal light transmitted by the LD 5 with a UV curing agent, solder, or the like. The PD 6b is soldered and electrically connected to the second electrode unit 35.

When the substrate material of the second substrate member 30 is made of single crystal silicon, the V groove 32 and the L
The D alignment mark can be formed at a time by anisotropic etching using a KOH solution or the like. In this case, since the positional relationship between the V-groove 32 and the LD alignment mark is determined by the accuracy of the photomask, the positional accuracy between these V-grooves 32 and the LD alignment mark can be kept high. For this reason, the deviation of the optical axis between the optical fiber 11 and the LD 5 arranged in the V-groove 32, etc.
It can be kept small enough to not be a problem.

As shown in FIG. 6, when the optical fiber 11 is disposed in the V-groove 32, the transmitting module 3 has a lid member for sandwiching and fixing the optical fiber 11 together with the V-groove 32. 36 are attached. The lid member 36 has a flat flat surface 37 overlapping the reference surface 31.

The lid member 36 extends over the V groove 32 and a flat surface 37 is superimposed on the reference surface 31.
It is adapted to be attached to the second substrate member 30. When attaching the lid portion 36 to the second substrate member 30, a UV curing agent, solder, or the like is used.

The optical transmitting / receiving module 1 includes the transmitting module 3 mounted on a glass substrate 38 having a flat surface.
It is fixed by bonding using a V curing agent or the like. Thereafter, the optical fiber 11 is disposed in the V-shaped groove 32 and the lid member 36 is disposed.
, And the wavelength demultiplexer 1 is adhered and fixed to a glass substrate 38 or the like.

According to the above configuration, the wavelength demultiplexer 1
Transmits signal light using the optical fiber 11 arranged in the V groove 14 of the first substrate member 10. For this reason, it is not necessary to form the optical waveguide by a film forming method or the like, so that the cost can be reduced as compared with the case where the signal light is transmitted using the optical waveguide having the core and the clad. Become. Further, since the optical fiber 11 generally has a lower loss than the optical waveguide, the wavelength demultiplexer 1 can suppress the loss when transmitting the signal light.

The wavelength demultiplexer 1 converts the signal light, for example, having a wavelength of 1.55 μm reflected by the filter 12
Since the light guide portion leading to D6a is a film 20 made of a mirror-like metal formed on the inner surfaces 17, 17 of the V-groove 11, the above-described reflection is provided by providing the PD 6a above the light guide portion. The transmitted signal light can be reliably guided to the PD 6a.

Further, a surface light receiving type PD 6a is used as the light receiving device, and the PD 6a along the first reference surface 13 is used.
The center O of the light receiving surface 22 of D6a and the optical axis P of the optical fiber 11
Even if the distance L between them becomes a relatively large value such as the aforementioned 13 μm to 45 μm, loss of the signal light received by the PD 6a can be suppressed.

For this reason, the positioning accuracy of the PD 6a on the first reference surface 13 and the inner surfaces 17 and 1 of the V-groove 14 are determined.
7 and the first reference plane 13, the molding accuracy such as the angle θ, the filter 12, the first reference plane 13 and the optical fiber 1
Accuracy requirements for the angle formed with one optical axis P can be relaxed. Therefore, the PD 6a, the optical fiber 11, the filter 12, and the like can be easily mounted, and the yield of the wavelength demultiplexer 1 can be improved.

The filter 12 is connected to the first reference plane 1.
3 and is inserted into the first substrate member 10 along a direction perpendicular to the third substrate 3. For this reason, it is possible to suppress the movement of the blade when the insertion groove 7 used for inserting the filter 12 is formed using a dicing machine or the like.
Therefore, since the insertion groove 7 can be formed without damaging the optical fiber 11, loss when the optical fiber 11 transmits signal light can be suppressed.

Further, since the optical fiber 11 is attached to the first substrate member 10 by the lid member 19, it is possible to prevent the optical fiber 11 from being displaced after being attached. Therefore, the PD 6a can more reliably receive the signal light, and the loss of the signal light received by the PD 6a can be suppressed.

The optical transmitting / receiving module 2 comprises a first
The wavelength demultiplexer 1 as the first optical device in which the PD 6a is disposed transmits the signal light by using the optical fiber 11 disposed in the V-groove 14 of the first substrate member 10. The cost can be reduced as compared with the case where the signal light is transmitted using the optical waveguide. In addition, since the optical fiber 11 that generally has lower loss than the optical waveguide is used, it is possible to suppress the loss when transmitting the signal light.

[0075]

According to the first aspect of the present invention, the wavelength demultiplexer transmits signal light using an optical fiber disposed in the V-groove of the substrate member. For this reason, it is not necessary to form an optical waveguide by a film forming method or the like as compared with a case where signal light is transmitted using an optical waveguide having a core and a clad, so that cost can be reduced. Become. In addition, since an optical fiber generally having a lower loss than that of the optical waveguide is used, it is possible to suppress a loss when transmitting the signal light.

According to the wavelength demultiplexer of the second and third aspects, in addition to the effect of the first aspect, since the light receiving device is a surface light receiving type photodiode, the positioning accuracy of the light receiving device and the filter are reduced. This makes it possible to relax the requirements for the accuracy of the insertion groove and the like used for insertion into the substrate member. Therefore, the mounting of the light receiving device becomes easy, and the cost can be reduced.

The wavelength demultiplexer according to the fourth aspect is the first aspect.
In addition to the effect of any one of the third to third aspects, the light guide for guiding the signal light reflected by the filter to the light receiving device is a film made of a mirror-like metal formed on the inner surface of the V groove. By providing a light receiving device above the light guide, the reflected signal light can be reliably guided to the light receiving device. Therefore, the light receiving device can be more easily mounted, and the cost can be further reduced.

The wavelength demultiplexer according to the fifth aspect is the first aspect.
In addition to the effect of any one of the fourth to fourth aspects, the filter is inserted into the substrate member along a direction perpendicular to the first reference plane. For this reason, it is possible to prevent the blade from moving when the insertion groove used for inserting the filter is formed using a dicing machine or the like. Therefore, it is possible to suppress damage to the optical fiber when forming the insertion groove, and it is possible to suppress a loss when the optical fiber transmits signal light.

The wavelength demultiplexer according to the sixth aspect is the first aspect.
In addition to the effect of any one of the fifth to fifth aspects, since the optical fiber is attached to the first substrate member by the lid member, it is possible to prevent the optical fiber from being displaced after being attached. Therefore, the light receiving device can more reliably receive the signal light, and the loss of the signal light received by the light receiving device can be suppressed.

According to a seventh aspect of the present invention, in the transmitting / receiving module, the first optical device on which the light receiving device is provided is a V-shaped substrate member.
Signal light is transmitted using an optical fiber arranged in the groove. For this reason, it is not necessary to form an optical waveguide by a film forming method or the like as compared with a case where signal light is transmitted using an optical waveguide having a core and a clad, so that cost can be reduced. Become. In addition, since an optical fiber generally having a lower loss than that of the optical waveguide is used, it is possible to suppress a loss when transmitting the signal light.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a wavelength demultiplexer according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II shown in FIG.

FIG. 3A is a plan view showing a first substrate member of the wavelength demultiplexer shown in FIG. 1; (B) is the same as III- in FIG.
Sectional drawing which follows the III line.

FIG. 4A is a plan view of the wavelength demultiplexer shown in FIG.
FIG. 4B is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a graph showing a relationship between a shift between the center of an optical fiber and the center of a light receiving surface of a PD in the wavelength demultiplexer shown in FIG.
The figure which shows the light reception rate of D.

FIG. 6 is a perspective view showing an optical transceiver module provided with the wavelength demultiplexer shown in FIG. 1;

FIG. 7 is a perspective view showing a transmission module of the optical transceiver module shown in FIG. 6;

FIG. 8 is a perspective view showing a conventional optical transceiver module.

FIG. 9 is a sectional view showing a conventional wavelength demultiplexer.

FIG. 10 is a cross-sectional view showing a conventional light receiving structure using a surface light receiving type PD.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Wavelength demultiplexer (1st optical device) 2 ... Optical transmission / reception module 3 ... Transmission module (2nd optical device) 5 ... Laser diode (light emitting device) 6a ... 1st photodiode (light receiving device) 6b ... Second photodiode (light receiving device) 10 ... First substrate member 11 ... Optical fiber 12 ... Filter 13 ... First reference surface 14 ... V groove 17 ... Inner surface 19 ... Lid member 19a ... Second reference surface 20 ... Mirror-like film (light guide)

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) H04B 10/04 10/06 (72) Inventor Chen Koyuki 3-10 Fukuura, Kanazawa-ku, Yokohama-shi, Kanagawa Japan Nippon Hatsujo Co., Ltd. F-term (reference) 2H047 BB14 CC07 5K002 AA05 AA07 BA05 BA31

Claims (7)

[Claims] A first substrate member provided with a light receiving device at a predetermined position and having a first reference surface formed flat and a V-groove formed concavely from the first reference surface; An optical fiber disposed in the V-groove; reflecting a signal light having a first wavelength transmitted through the optical fiber and transmitting a signal light having a second wavelength transmitted through the optical fiber; A filter inserted into the substrate member by dividing a fiber; and a light guide unit for guiding the signal light having the first wavelength reflected by the filter to the light receiving device. Wavelength splitter. 2. The wavelength demultiplexer according to claim 1, wherein the light receiving device is disposed above the filter and the light guide. 3. The wavelength demultiplexer according to claim 1, wherein the light receiving device is a photodiode of a surface light receiving type. 4. The light guide section according to claim 1, further comprising a mirror-like film formed at least near the filter on the inner surface of the V-groove. The wavelength demultiplexer according to claim 1. 5. The filter according to claim 1, wherein the filter is inserted into the substrate member along a direction perpendicular to a first reference plane of the substrate member. The wavelength demultiplexer according to any one of the above. 6. A lid member having a second reference surface formed flat and overlapping the first reference surface across the V groove,
2. The device according to claim 1, wherein the device is attached to the substrate member.
A wavelength demultiplexer according to claim 5. 7. A V-shaped groove in which an optical fiber is arranged and a flat first groove along the optical fiber in which a light receiving device is arranged at a predetermined position.
A first substrate member having a reference surface, and a signal light having a first wavelength, which is inserted into the first substrate member by dividing the optical fiber and is transmitted through the optical fiber, and reflects the signal light. A first filter having a filter that transmits a signal light having a second wavelength transmitted through an optical fiber; and a light guide unit that guides the signal light having the first wavelength reflected by the filter to the light receiving device. An optical transmitting and receiving module, comprising: an optical device according to (1), a V-groove for disposing the optical fiber, and a light emitting device that emits signal light to the optical fiber.