KR101630354B1

KR101630354B1 - Bidirectional optical transceiver module

Info

Publication number: KR101630354B1
Application number: KR1020120099200A
Authority: KR
Inventors: 김민수; 박선택; 주정진
Original assignee: 한국전자통신연구원
Priority date: 2011-10-06
Filing date: 2012-09-07
Publication date: 2016-06-14
Also published as: KR20130037632A

Abstract

The present invention provides a bidirectional optical transmission / reception module having an optical coupling structure that is applicable to high-speed and large-capacity data communication and is advantageous in integration and cost reduction of modules. The bidirectional optical transceiver module according to an embodiment of the present invention includes a first structure having a hexahedron shape in which at least two side faces of the four side faces are inclined at a predetermined angle with respect to the bottom face and both transmission light and transmitted light are transmitted; And at least one second structure having a planar shape and perpendicular to the bottom surface and interposed in the first structure in a shape that is different from the direction of the transmission light or the received light by a predetermined angle, And one of the transmission light and the reception light is transmitted and the other is reflected.

Description

[0001] BIDIRECTIONAL OPTICAL TRANSCEIVER MODULE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a bidirectional optical transmission / reception module, and more particularly, to a technique for efficiently configuring a multi-channel bidirectional optical transmission / reception module.

With the development of information and communication technology and its diversification, there is a need for a high-speed and high-capacity information transmission technology based on optical communication in a short distance data communication area within several tens of meters as well as telecommunication of several tens of kilometers to several hundreds km Application is rapidly expanding. In recent years, there is a need to apply high-speed and high-capacity data communication technology even in a very short range of several meters to several centimeters, such as information transmission between computers and peripheral devices, signal transmission for high-resolution video devices, and signal transmission between boards in mobile devices . Accordingly, integration and cost reduction of the optical transmission / reception module are becoming important technical issues.

As a representative technology to cope with a rapid increase in demand for information transmission technology based on optical communication, proposed is a technique for improving the optical signal transmission rate per channel and a technique for parallel optics using a plurality of optical fiber lines . However, the increase in the number of optical fiber lines leads to an increase in the volume of the optical transmission / reception module, which is a negative factor in module integration.

On the other hand, in a conventional subscriber network optical transmission / reception system, a bidirectional optical transmission / reception module applying different wavelengths to both the upstream and downstream sides of the same optical fiber line has been considered as an important technical element in terms of integration and cost reduction. Is often referred to as a Bidirectional Optical Subassembly (BOSA) or BiDi module.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram showing a general configuration of a conventional BiDi module. FIG.

Referring to FIG. 1, a conventional BiDi module includes an optical fiber 101, an optical filter 103, a light source device 105, and a light receiving device 107. The optical filter 103 imparts different optical paths to the transmission light and the reception light having different wavelengths (? ₁ ,? ₂ ), and the light source element 105 and the light reception element 107 in the TO- Are arranged at an angle of 90 degrees with respect to the optical filter 103.

In order to integrate and reduce the price of the optical transceiver module for high-speed and large-capacity data communication, the construction principle of the BiDi module of FIG. 1 can be applied. In this case, it is possible to reduce the number of transmission lines of the optical transceiver module by half. However, in the configuration based on the TO-can package, the integration of the module still has a limitation. When a high-speed signal of 10 Gbps or higher is transmitted, the distance between the light source device and the driver IC, the distance between the light receiving device and the amplifier IC It is necessary to improve the fundamental composition. Further, even when an optical fiber array is applied to meet the necessity of large-capacity information transmission, it is necessary to construct an optical transmission / reception module capable of more efficient optical coupling and alignment, apart from the two-dimensional configuration of existing BiDi modules.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a bidirectional optical transmission / reception module having an optical coupling structure which is applicable to high-speed and large-capacity data communication and is advantageous in integration and cost reduction of modules.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a bidirectional optical transceiver module comprising: a first structure having a hexahedron shape in which at least two side faces of the four side faces are inclined at a predetermined angle with a bottom face; At least one second structure having a planar shape and perpendicular to the bottom surface and interposed in the first structure in a shape that is different from a direction of the transmission light or the received light by a predetermined angle; . The light emitting device may further include a circuit board on which at least one light source element and at least one light receiving element are integrated and which has parallel optical axes opposite to the first structure and an optical transmission medium disposed in proximity to or in contact with one side of the first structure .

The first structure transmits both transmission light and reception light of different wavelengths, and the second structure transmits one of the transmission light and the reception light and reflects the other transmission light.

The bidirectional optical T / R module may further include a reflective layer formed on an inclined side surface of the first structure.

Wherein the bidirectional optical T / R module comprises at least two lenses formed on an area of the bottom surface of the first structure covered by the inclined side surface; And the transmission light and the reception light may be incident or emitted through the lens.

Wherein the bidirectional optical transceiver module further comprises at least one lens formed on a side surface of the first structure in which the optical transmission medium is in contact or in contact with the optical path between the first structure and the optical transmission medium .

The second structure may be implemented with an optical filter or a dichroic beam splitter.

According to the present invention, by applying the coupling structure of the first structure in the form of a hexahedron having two or more sides inclined to the optical transmission / reception module of the multi-channel array structure and the second structure interposed therebetween, The integration and cost reduction of the transmission / reception module can be obtained.

Also, the distance between the light source device and the light receiving device and the electronic IC can be reduced through effective space utilization, thereby improving the transmission / reception performance of a high-speed optical signal.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a general configuration of a conventional BiDi module. FIG.
FIG. 2A and FIG. 2B are block diagrams of a bidirectional optical T / R module according to an embodiment of the present invention;
Fig. 2C is a modification of the embodiment of Figs. 2A and 2B. Fig. 2C shows an example in which the inclined side surface of the first structure is embodied as a convex mirror.
3 is a block diagram of a bidirectional optical T / R module according to another embodiment of the present invention.
4 is a view for explaining a method of operating the bidirectional optical T / R module according to the embodiment of FIGS. 2A and 2B.
5 illustrates a bidirectional optical transceiver module that further includes a circuit board on which a multi-channel light source element and a light receiving element are integrated in the embodiment of Figs. 2A and 2B. Fig.

The above and other objects, features, and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings, which are not intended to limit the scope of the present invention. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2A and 2B are block diagrams of a bidirectional optical T / R module according to an embodiment of the present invention. Figure 2a is a plan view of the module, and Figure 2b is a front view.

2A and 2B, the first and second side surfaces 201 and 202 of the four side surfaces of the bidirectional optical T / R module according to the embodiment of the present invention have a predetermined angle with respect to the bottom surface 205 The first structure 20 has a planar shape and is formed at a right angle to the bottom surface 205. The first structure 20 has a predetermined angle with respect to the direction of transmission light or transmitted light The second structure 21 interposed in the first structure 20 in such a manner that the second structure 21 is deformed by as much as 45 degrees in the example). At this time, the first structure 20 transmits both transmission light and reception light of different wavelengths, and the second structure 21 has a property of transmitting one of transmission light and reception light and reflecting the other.

The surfaces of the first and second side surfaces 201 and 202 are covered with the first and second side surfaces 201 and 202 of the bottom surface 205, A reflective layer coated with a metal or a dielectric material may be further formed to improve the optical coupling efficiency. In addition, a structure having a predetermined refractive index difference may be additionally provided in a specific region in the first structure 20, or a change in the refractive index of the first structure 20 may be induced, An effect of reducing light loss due to diffusion and scattering may be obtained.

A plurality of lenses 207 may be formed on the bottom surface 205 of the first structure 20 for efficient optical coupling using the focusing effect of light. Specifically, the plurality of lenses 207 are arranged in a region covered by the first and second side surfaces 201 and 202 of the bottom surface 205 of the first structure 20, that is, And the exit surface. In this case, since the optical paths for the two wavelengths of light are all the same, the same structure can be applied to all the lenses 207 formed on the bottom surface 207 according to the design and manufacturing requirements.

One or more lenses 209 for optical coupling with the optical transmission medium (see FIGS. 4 and 5) are further provided on the third side 203, which is perpendicular to the bottom surface 205, of the four sides of the first structure 20 .

As the second structure 21, an optical filter or a dichroic beamsplitter may be applied.

2C, the two sides of the first structure 20 may be replaced by the convex mirror structures 201-1, 201-2, 201-3 instead of the plurality of lenses 207 formed on the bottom surface 205 of the first structure 20. [ 202-1). In this case, since the convex mirror structures 201-1 and 202-1 substitute for the light focusing function of the lens 207, almost the same effect as the lens structure of FIGS. 2A and 2B can be obtained.

As in the above embodiment, the second structure 21 is formed as a single structure and interposed in the first structure 20 is ideal in terms of cost reduction of the module. However, if necessary, And the case where it is intervened can be considered.

FIG. 3 is a block diagram of a bidirectional optical T / R module according to another embodiment of the present invention, in which two second structures 31 and 32 are interposed in the first structure 30. 3, the first, second, and third side surfaces 301, 302, and 304 of the four side surfaces are connected to the bottom surface 205 at a predetermined angle (in this embodiment, 45 The first structure 30 has a planar shape and is formed at a right angle to the bottom surface 205 and has a predetermined angle with respect to the direction of transmitted light or transmitted light (in this embodiment, And two second structures 31 and 32 interposed in the first structure 30 in a shape that is different by 45 degrees and -45 degrees, respectively. At this time, the first structure 30 transmits both transmission light and reception light of different wavelengths, and the second structures 31 and 32 transmit the transmission light and the reception light, I have.

In this embodiment, the first second structure 31 reflects light coming through the fourth side 303 of the first structure 30 to the first side 301 and the second second structure 32 reflects light And reflects light received through the four side faces 303 to the third side face 304. In this case, the width of the first structure 30 is reduced to about half as compared with the embodiment of FIGS. 2A and 2B, and the light path is shortened.

FIG. 4 is a view for explaining the operation of the bidirectional optical T / R module according to the embodiment of FIGS. 2A and 2B.

In Fig. 4, the arrow lines drawn in two different directions represent transmit light with wavelength λ ₁ and receive light with wavelength λ ₂ , respectively.

The transmitted light incident on the first structure 20 through the lens 207 formed on the bottom surface 205 of the first structure 20 is reflected by the second side 202 and passes through the second structure 21 as it is And enters the optical transmission medium 40 through the lens 209 formed on the third side 203. Conversely, the incoming light from the optical transmission medium 40 enters the first structure 20 through the lens 209, is reflected by the second structure 21, is again reflected from the first side 201, And is emitted through the lens 207 of the lens 205. As described above, it is possible to realize an efficient bidirectional optical transmission / reception module by using the first structure 20 having a unique shape and the second structure 21 having different transmission or reflection characteristics depending on the wavelength.

5 is a diagram illustrating a bidirectional optical transceiver module including a circuit board on which a multi-channel light source element and a light receiving element are integrated in the embodiment of FIGS. 2A and 2B.

5, the bidirectional optical T / R module according to an embodiment of the present invention includes a circuit board 50 on which one or more light source elements 501 having a parallel optical axis and one or more light receiving elements 503 are integrated, The bottom surface 205 is opposed to the substrate 50 and the first and second side surfaces 201 and 202 of the four side surfaces are inclined to form a predetermined angle with the bottom surface 205, The first structure 20 has a planar shape and is perpendicular to the bottom surface 205. The first structure 20 has a shape that is different from the direction of the transmitted light or the received light by a predetermined angle (45 degrees in this embodiment) A second structure 21 interposed in the first structure 20 and a light transmission medium 40 disposed in proximity to or in contact with the third side 203 of the first structure 20. The second structure 21 has a property of transmitting one of the transmission light and the reception light and reflecting the other.

It is preferable that the bottom surface 205 of the first structure 20 is disposed opposite to the circuit board 50 on which the plurality of light source elements 501 and the light receiving elements 503 are integrated. And the light receiving element 503 are arranged on the circuit board 50 in alignment with the optical axis of light incident on or emitted from the bottom surface 205 of the first structure 20. In this case, an alignment pin or an alignment groove (not shown) may be additionally formed in a specific area of the circuit board 50 and the first structure 20, and the light source device 501 and the light receiving device 503 ) And the first structure 20 can be further improved. This structure eliminates the problem that the light source device and the light receiving device are separately housed or mounted on a separate substrate when the conventional structure as shown in FIG. 1 is applied, and is very advantageous in terms of integration and cost reduction of the optical module do.

The optical coupling structure as shown in FIG. 5 may be implemented by mounting an electronic IC 505 element such as a driver or an amplifier, which is essential for driving the light source element 501 and the light receiving element 503, It also has a great advantage in terms of size. In the high-speed optical T / R module, if the distance between the driver and the light source element, the distance between the amplifier and the light receiving element is large, a serious performance deterioration occurs. This problem can be easily solved when the electronic IC 505 is mounted so as to be adjacent to the light source element 501 and the light receiving element 503 in the region where the light emitting element 501 and the light receiving element 503 are disposed.

In this case, a multi-channel driver and a multi-channel amplifier may be mounted adjacent to the light source element array and the light receiving element array, respectively, as needed, in addition to a method of mounting a single electronic IC for integrally driving the multi-channel light source element and the light receiving element. Or a method of mounting a separate driver and amplifier for each channel is also applicable.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. For example, it is also possible to form a lens on the optical fiber, the light source element, and the light receiving element side without forming a lens on the light incident surface and the emission surface of the first structure, or to form a separate lens therebetween, This is obvious. It is also conceivable that the bottom surface of the first structure and the side coupled with the optical transmission medium form an angle of 45 degrees and the lens of the area to be coupled with the optical transmission medium is also formed on the bottom surface. It can be easily understood that there is no difference in the other respects except that it is vertically mounted on the coupling structure and the circuit board.

20, 30: First structure
21, 31, 32: second structure
201 to 204, 301 to 304: First to fourth sides of the first structure
205: bottom surface of the first structure
207, 209, 307, 309: lens
201-1, 202-1: first and second side surfaces in the form of a convex mirror
40: optical transmission medium
50: circuit board
501: Light source element
503: Light receiving element
505: Electronic IC

Claims

Characterized in that at least two side faces of the side face of the hexahedron are inclined at a predetermined angle with the bottom face to transmit both the transmission light and the reception light;
At least one second structure having a planar shape and being perpendicular to the bottom surface and interposed in the first structure in a shape that is different from a direction of the transmission light or the received light by a predetermined angle; Lt; / RTI >
And the second structure transmits one of the transmission light and the reception light and reflects the other light.
Bidirectional optical transceiver module.

The method according to claim 1,
A reflective layer formed on the inclined side surface; Further comprising
Bidirectional optical transceiver module.

The method according to claim 1,
At least two lenses formed on the bottom surface of the first structure in a region covered by the inclined side surface; Further comprising:
And the transmission light and the reception light are incident or emitted through the lens
Bidirectional optical transceiver module.

The method according to claim 1,
And the angle between the inclined side surface and the bottom surface is 45 degrees.
Bidirectional optical transceiver module.

The method according to claim 1,
Wherein the inclined side surface is formed in a convex mirror shape
Bidirectional optical transceiver module.

The method according to claim 1,
And the angle formed by the direction of the transmission light or the transmitted light and the second structure is 45 degrees.
Bidirectional optical transceiver module.

The method according to claim 1,
Characterized in that the second structure is an optical filter or a dichroic beam splitter
Bidirectional optical transceiver module.

A circuit board on which at least one light source element having a parallel optical axis and at least one light receiving element are integrated;
At least two side faces of the hexahedron are inclined at a predetermined angle with respect to the bottom face to transmit both the transmission light and the received light, Feature;
At least one second structure having a planar shape and being perpendicular to the bottom surface and interposed in the first structure in a shape that is different from a direction of the transmission light or the received light by a predetermined angle; And
An optical transmission medium disposed in proximity to or in contact with one side of the first structure; / RTI >
And the second structure transmits one of the transmission light and the reception light and reflects the other light.
Bidirectional optical transceiver module.

9. The method of claim 8,
A reflective layer formed on an inclined side surface of the first structure; Further comprising
Bidirectional optical transceiver module.

9. The method of claim 8,
Wherein the at least one light source element is arranged to direct light through a bottom surface of the first structure to an oblique side of the first structure and the at least one light receiving element is reflected from another inclined side of the first structure And is arranged to collect light emitted through the bottom surface of the first structure
Bidirectional optical transceiver module.

11. The method of claim 10,
At least two lenses formed on the bottom surface of the first structure in a region covered by the inclined side surface; Further comprising:
Wherein the transmission light output from the light source element is incident on the first structure through a part of the lenses and the received light is outputted through the remaining of the lenses and input to the light receiving element
Bidirectional optical transceiver module.

9. The method of claim 8,
And the angle between the inclined side surface and the bottom surface is 45 degrees.
Bidirectional optical transceiver module.

9. The method of claim 8,
At least one lens formed on a side surface of the first structure in which the optical transmission medium is in contact or in contact; Further comprising:
Wherein a light path is formed between the first structure and the light transmission medium through the lens
Bidirectional optical transceiver module.

9. The method of claim 8,
Characterized in that the optical transmission medium is an optical fiber or a planar optical waveguide
Bidirectional optical transceiver module.

9. The method of claim 8,
Wherein the inclined side surface is formed in a convex mirror shape
Bidirectional optical transceiver module.

9. The method of claim 8,
And the angle formed by the direction of the transmission light or the transmitted light and the second structure is 45 degrees.
Bidirectional optical transceiver module.

9. The method of claim 8,
Characterized in that the second structure is an optical filter or a dichroic beam splitter
Bidirectional optical transceiver module.

9. The method of claim 8,
An electronic IC mounted on the circuit board in a region adjacent to the light source element and the light receiving element to drive the light source element and the light receiving element; Further comprising
Bidirectional optical transceiver module.