Single-fiber bidirectional multichannel optical transceiver module

Abstract

A single-fiber bidirectional multichannel optical transceiver module comprises a shell, an optical transmitting assembly, an optical receiving assembly and an optical fiber adapter. The shell is provided with an accommodating cavity. The light emitting assembly is arranged in the containing cavity and comprises a plurality of light emitting units and wavelength division multiplexers arranged corresponding to the light emitting units. The optical receiving assembly is arranged in the accommodating cavity and comprises a plurality of optical receiving units and wavelength division demultiplexers arranged corresponding to the optical receiving units. The optical fiber adapter is arranged in the shell.

Description

Technical Field

[0001] The invention relates to a single-fiber bidirectional multi-channel optical transceiver module, in particular to a single-fiber bidirectional multi-channel optical transceiver module with a simplified packaging structure. Background Art

[0002] In modern high-speed optical communication networks, optical communication devices are usually installed in electronic communication equipment. With the upgrade of communication systems and the rapid increase in the demand for communication bandwidth for various Internet services, existing communication systems have two major problems that need to be overcome: insufficient internal storage space and high energy consumption. How to provide a communication system with small size, high internal space utilization and low energy consumption while improving bandwidth and transmission rate is one of the important topics in this technical field.

[0003] With the gradual development of high-speed optical communication networks, in order to ensure the high configuration density of optical modules, single-fiber bidirectional design is used as an optical module architecture replacement solution for traditional single-fiber unidirectional design. Generally speaking, a single-fiber bidirectional optical module can include a main shell provided with an optical fiber adapter and an optical path turning element and a sub-shell provided with an optical transmission sub-module or an optical reception sub-module, and the optical coupling between the optical transmission / light reception sub-module and the optical fiber adapter is realized by assembling the sub-shell with the main shell. However, in order to comply with the MSA (Multi-Source Agreement), the single-fiber bidirectional optical module may need to be designed to be airtight, but the optical module architecture assembled by the aforementioned sub-shell and the main shell makes it difficult to achieve airtightness. In addition, in response to the application of passive optical fiber networks (PON) in high-speed optical communication networks, the combination of traditional electro-absorption modulated lasers (EML) and semiconductor optical amplifiers (SOA) integrated chips can no longer meet the requirements of high-speed PONs such as 50G (Gbps). Summary of the invention

[0004] The present invention provides a single-fiber bidirectional multi-channel optical transceiver module, which helps to solve the problem that the architecture of the existing single-fiber bidirectional optical module is difficult to achieve airtight packaging and cannot meet the requirements of high-speed PON.

[0005] The single-fiber bidirectional multi-channel optical transceiver module disclosed in the present invention comprises a housing, an optical transmitting component, an optical receiving component and an optical fiber adapter. The housing has a receiving cavity. The optical transmitting component is arranged in the receiving cavity and comprises a plurality of optical transmitting units and a wavelength division multiplexer arranged corresponding to the optical transmitting units. The optical receiving component is arranged in the receiving cavity and comprises a plurality of optical receiving units and a wavelength division multiplexer arranged corresponding to the optical receiving units. The optical fiber adapter is arranged in the housing.

[0006] According to the single-fiber bidirectional multi-channel optical transceiver module disclosed by the present invention, the optical transmitting component and the optical receiving component are arranged in the same accommodating cavity, or even the optical transmitting component, the optical receiving component and the optical path turning component are arranged in the same accommodating cavity. Thus, compared with the existing optical module architecture, the optical transceiver module of the present invention is conducive to airtight packaging and has better structural stability.

[0007] In addition, a low-cost lithium niobate modulator is used to modulate the optical signal, so that the wavelength and bandwidth of the modulated optical signal meet the requirements of high-speed long-distance transmission. The combination of electro-absorption modulated laser and lithium niobate modulator is also conducive to adjusting the output power and extinction ratio of the optical signal to meet the requirements of high-speed PON.

[0008] The above description of the content of the present invention and the following description of the implementation modes are used to demonstrate and explain the spirit and principle of the present invention, and to provide further explanation for the protection scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 The figure is a schematic diagram of an existing single-fiber bidirectional optical transceiver module.

[0010] Figure 2 FIG. 4 is a schematic diagram of a single-fiber bidirectional optical transceiver module according to an embodiment of the present invention.

[0011] Figure 3 for Figure 2 Schematic diagram of the optical transmission components in .

[0012] Figure 4 for Figure 2 Schematic diagram of the optical path of the light emitting component in FIG.

[0013] Figure 5 for Figure 2 Schematic diagram of the optical path of the light receiving component in FIG.

[0014] [Description of Reference Numerals]

[0015] Optical transceiver module 1, 1A

[0016] Light emitting submodule 10

[0017] TO package shell 11, 12

[0018] Main housing 13

[0019] Light receiving submodule 20

[0020] Optical path turning element 30

[0021] Housing 10A

[0022] Accommodating chamber 100

[0023] Main body 110

[0024] Ceramic circuit board 120 optical emitting component 20A

[0025] Light emitting unit 210 Electroabsorption modulated laser 210a Direct modulated laser 210a" Continuous wavelength laser 210b Lithium niobate modulator 220 Light receiving port 221

[0026] Light outlet 222

[0027] WDM 230

[0028] Optical waveguide body 231 Bandpass filter group 232 Total reflection unit 233

[0029] Anti-reflective film 234

[0030] Thermoelectric Cooler 240

[0031] Thermistor 250

[0032] Coupling lens 260

[0033] Optical isolator 270

[0034] Heat sink 280

[0035] Light receiving unit 30A

[0036] Light receiving unit 310 wavelength division multiplexer 320 optical waveguide body 321 bandpass filter group 322 total reflection unit 323

[0037] Anti-reflection film 324 Light path turning unit 330

[0038] Fiber Optic Adapter 40A

[0039] Ceramic Ferrule 410

[0040] Ceramic sleeve 420

[0041] First optical path turning element 50

[0042] Optical surfaces 510, 520, 530, 540

[0043] The second optical path turning element 60 DETAILED DESCRIPTION

[0044] The detailed features and advantages of the present invention are described in detail in the following embodiments, and the contents are sufficient to enable ordinary technicians in the field to understand the technical content of the present invention and implement it accordingly. According to the contents, protection scope and drawings disclosed in this specification, ordinary technicians in the field can easily understand the relevant purposes and advantages of the present invention. The following examples are to further illustrate the viewpoints of the present invention in detail, but are not intended to limit the scope of the present invention in any way.

[0045] Please refer to Figure 1 , is a schematic diagram of an existing single-fiber bidirectional optical transceiver module. The single-fiber bidirectional optical transceiver module 1 may include an optical transmitting submodule 10 , an optical receiving submodule 20 , and an optical path turning element 30 .

[0046] The optical transmitting submodule 10 can be accommodated in a TO (transistor outline) package shell 11, and the optical transmitting submodule 10 can include a laser transmitter, a thermoelectric cooler, a coupling lens, and an optical isolator. The optical receiving submodule 20 can be accommodated in another TO package shell 12, and the optical receiving submodule 20 can include a photodiode and a transimpedance amplifier (TIA). The optical path turning element 30 can be accommodated in the main housing 13, and the optical path turning element 30 can be a filter. The filter can allow the optical signal output by the optical transmitting submodule 10 to pass through and be transmitted to the optical fiber port located in the main housing 13. In addition, the filter can change the transmission direction of the external optical signal input from the optical fiber port to be transmitted toward the optical receiving submodule 20.

[0047] The TO package shells 11 and 12 can be welded with the main housing 13 to achieve optical coupling between the optical transmitting submodule 10, the optical receiving submodule 20 and the optical fiber port. However, it is difficult to implement airtight packaging with this existing architecture. For example, it is difficult to maintain a tight fit between the TO package shells 11 and 12 and the main housing 13 for a long time, or a transparent airtight window needs to be installed, resulting in excessively high manufacturing costs. Therefore, the present invention provides one or more improvements to a single-fiber bidirectional optical transceiver module to solve the above problems.

[0048] Please refer to Figure 2 and Figure 3 ,in Figure 2 is a schematic diagram of a single-fiber bidirectional optical transceiver module according to an embodiment of the present invention, and Figure 3 for Figure 2 In this embodiment, the optical transceiver module 1A may be a single-fiber bidirectional multi-channel optical transceiver module, which may include a housing 10A, an optical transmitting component 20A, an optical receiving component 30A, and an optical fiber adapter 40A.

[0049] The housing 10A may have an airtight or non-airtight accommodating cavity 100. Specifically, the housing 10A may include a main body 110 and a ceramic circuit board 120, and the ceramic circuit board 120 is fixed to the main body 110 by sealing solder to form the accommodating cavity 100. In this embodiment, the accommodating cavity 100 is an independent single airtight chamber.

[0050] The light emitting component 20A is disposed in the accommodating cavity 100, and the light emitting component 20A may include a plurality of light emitting units 210 and a thin film lithium niobate (LiNbO3) modulator 220. Each light emitting unit 210 is, for example but not limited to, a laser emitter, and the bandwidth and optical wavelength of this laser emitter are not limited. The lithium niobate modulator 220 may include a packaging structure and a lithium niobate chip located in the packaging structure. The ceramic circuit board 120 may be electrically connected to the light emitting unit 210 and the lithium niobate modulator 220. The lithium niobate modulator 220 may have a light receiving port 221 and a light emitting port 222 located on the same side. The lithium niobate modulator 220 is disposed corresponding to at least one of the light emitting units 210. Furthermore, the light emitting unit 210 of the present embodiment may include an electro-absorption modulated laser 210a, a directly modulated laser (DML) 210a″ and a continuous wavelength laser (CW Laser) 210b. The electro-absorption modulated laser 210a and the directly modulated laser 210a″ may, for example, output optical signals of 1490 nanometers and 1577 nanometers, respectively. The continuous wavelength laser 210b may, for example, output an optical signal of 1064 nanometers, and the optical signal may be received by the lithium niobate modulator 220 via the light receiving port 221. The lithium niobate modulator 220 may modulate the optical signal and then output the modulated optical signal via the light output port 222. The number of the aforementioned electro-absorption modulated lasers and directly modulated lasers is not intended to limit the present invention.

[0051] The optical emitting component 20A may further include a wavelength division multiplexer 230 corresponding to these optical emitting units 210 to meet the PON application requirements. The wavelength division multiplexer 230 may be a Z-block, which may include an optical waveguide body 231, a bandpass filter group 232, a total reflection unit 233 and an anti-reflection film 234. The optical waveguide body 231 is a flat quadrilateral block or a diamond block, and its transverse cross-sectional dimensions can meet the conditions of single-mode transmission. The preparation material of the optical waveguide body 231 can adopt any waveguide material used in conventional processes, such as silicon dioxide, a composite material formed by stacking silicon layers and germanium layers, a composite material formed by stacking silicon layers and silicon dioxide layers, etc. The bandpass filter group 232 is located on the light input side of the optical waveguide body 231 ( Figure 3 The bandpass filter group 232 may include a plurality of filters with different bandpasses, and the applicable wavelength band of each filter corresponds to the working wavelength of each light emitting unit 210 (each channel). The bandpass filter group 232 can allow the light in the applicable wavelength band to penetrate, and reflect the light outside the applicable wavelength band. The multiple filters of the bandpass filter group 232 can be an integrally formed object, or they can be independent filter arrays. The total reflection units 233 are respectively located on the light output side ( Figure 3In the embodiment, the total reflection unit 233 can realize a coating or a reflector that reflects all wavelengths of light. The anti-reflection film 234 is respectively located on the light output side of the light waveguide body 231, and the total reflection unit 233 does not cover the anti-reflection film 234; in other words, the anti-reflection film 234 is arranged in the area of ​​the light output side of the light waveguide body 231 that does not overlap with the anti-reflection film 234. In other embodiments, if the light does not generate severe refraction or total reflection at the interface between the light waveguide body and the air, it is not necessary to additionally set an anti-reflection film.

[0052] In addition, the optical transmitter assembly 20A may further include a thermoelectric cooler 240, a thermistor 250, a coupling lens 260, an optical isolator 270, and a heat sink 280. These devices may work together with the optical transmitter unit 210 and / or the lithium niobate modulator 220, so that the optical transmitter assembly 20A can be used as a light transmitting submodule (TOSA).

[0053] The light receiving assembly 30A is disposed in the accommodating cavity 100, and the light receiving assembly 30A may include a plurality of light receiving units 310 and a wavelength division multiplexer 320 disposed corresponding to the light receiving units 310. The light receiving unit 310 is, for example but not limited to, a combination of a photodiode and a transimpedance amplifier (TIA), and the ceramic circuit board 120 may be electrically connected to the light receiving unit 310. In this embodiment, the light receiving unit 310 and the light emitting unit 210 may have the same number.

[0054] The wavelength division multiplexer 320 may be a Z-block, which may include an optical waveguide body 321, a bandpass filter group 322, a total reflection unit 323, and an anti-reflection film 324. The optical waveguide body 321 is a flat quadrilateral block or a rhombus block, and its transverse cross-sectional dimensions can meet the conditions for single-mode transmission. The preparation material of the optical waveguide body 321 can adopt any waveguide material used in conventional processes, such as silicon dioxide, a composite material formed by stacking silicon layers and germanium layers, a composite material formed by stacking silicon layers and silicon dioxide layers, etc. The bandpass filter group 322 is located on the light input side ( Figure 3 The bandpass filter group 322 may include a plurality of filters with different bandpasses, and the applicable wavelength band of each filter corresponds to the applicable wavelength of each light receiving unit 310. The bandpass filter group 322 can allow light in the applicable wavelength band to penetrate, and reflect light outside the applicable wavelength band. The multiple filters of the bandpass filter group 322 can be an integrally formed object, or they can be independent filter arrays. The total reflection units 323 are respectively located on the light output side ( Figure 3In this embodiment, the total reflection unit 323 can realize a coating or a reflector that reflects all wavelengths of light. The anti-reflection film 324 is respectively located at the light output side of the optical waveguide body 321. In other embodiments, it is not necessary to additionally set an anti-reflection film.

[0055] In this embodiment, the light receiving assembly 30A may further include an optical path turning unit 330, and the optical path turning unit 330 may be disposed between the wavelength division multiplexer 320 and the light receiving unit 310. The optical path turning unit 330 may be a reflector or a combination of a reflector and a lens. Since the light receiving surface of the light receiving unit 310 faces upward, the optical path turning unit 330 can change the horizontally transmitted optical signal into a vertically transmitted optical signal so as to be received by the light receiving unit 310.

[0056] In addition, the optical receiving component 30A may also include a coupling lens, an optical isolator, and a transimpedance amplifier for converting a current signal into a voltage signal. These devices can work together with the optical receiving unit 310, so that the optical receiving component 30A can be used as a receiving optical submodule (ROSA).

[0057] The optical fiber adapter 40A can be disposed in the housing 10A. Specifically, the optical fiber adapter 40A can be coupled to the main body 110 of the housing 10A to serve as an optical fiber port. The optical fiber adapter 40A can include a ceramic ferrule 410 and a ceramic sleeve 420 for inserting an external optical fiber (not shown).

[0058] The optical transceiver module 1A of the present embodiment may further include a first optical path turning element 50 and a second optical path turning element 60. The first optical path turning element 50 and the second optical path turning element 60 may be disposed in the accommodating cavity 100. The first optical path turning element 50 is disposed between the optical fiber adapter 40A and the wavelength division multiplexer 230 of the optical transmitting component 20A, and the second optical path turning element 60 is disposed at the optical transmitting end of the first optical path turning element 50.

[0059] The first optical path turning element 50 may be a beam splitter prism, which is used to change the transmission direction of the optical signal input from the optical fiber adapter 40A to be transmitted toward the optical receiving component 30A. In addition, the first optical path turning element 50 also allows the optical signal output from the optical transmitting component 20A to pass through and be transmitted to the optical fiber adapter 40A. The second optical path turning element 60 may be a reflector, which is used to change the transmission direction of the optical signal output from the optical transmitting end of the first optical path turning element 50 to be transmitted toward the wavelength division multiplexer 320 of the optical receiving component 30A.

[0060] Figure 4 for Figure 2Schematic diagram of the optical path of the optical emitting component in FIG. The light generated by the optical emitting unit 210 (including the optical signal output by the self-electroabsorption modulated laser, the direct modulated laser and the lithium niobate modulator 220) passes through the coupling lens 260 to form parallel light, and then the three-way (channel) light passes through the bandpass filter set 232 of the wavelength division multiplexer 230 and enters the optical waveguide body 231. Under the reflection of the total reflection unit 233, the channel light enters the next waveguide section along the Z-shaped or W-shaped waveguide optical path in sequence for propagation. Under the restriction of the optical waveguide on the propagation direction of the light, the three-way light finally passes through the anti-reflection film 234 and then passes through the optical isolator 270 and the first optical path turning element 50 to couple with the external optical fiber inserted in the optical fiber adapter 40A.

[0061] Figure 5 for Figure 2 Schematic diagram of the optical path of the optical receiving component in FIG. The external optical signal enters the housing 10A via the optical fiber adapter 40A. The external optical signal enters the interior of the first optical path turning element 50 through the optical surface 510, and the external optical signal can be refracted at the optical surface 510 to make an optical path turn. It is reflected by the optical surfaces 520 and 530 of the first optical path turning element 50 and makes at least two optical path turns, and then leaves the first optical path turning element 50 through the optical surface 540 (i.e., the light emitting end of the first optical path turning element 50). The external optical signal leaving the first optical path turning element 50 is transmitted to the second optical path turning element 60 and is reflected by the second optical path turning element 60 and makes at least one optical path turn, and then enters the optical waveguide body 321 of the wavelength division multiplexer 320. Under the reflection action of the total reflection unit 323, the external optical signal enters the next waveguide section in sequence along the Z-shaped or W-shaped waveguide optical path to propagate, and finally three light beams with different wavelengths can be obtained. In this way, the external optical signal can be received by the optical receiving unit 310 which is not coaxial with the optical fiber adapter 40A. The optical receiving unit 310 can respond to the received external optical signal and convert it into an electrical signal. The number of optical path turns mentioned above is not intended to limit the present invention.

[0062] According to the single-fiber bidirectional multi-channel optical transceiver module disclosed in the present invention, the optical transmitting component and the optical receiving component are arranged in the same accommodating cavity, or even the optical transmitting component, the optical receiving component and the optical path turning component are arranged in the same accommodating cavity. Thus, compared with the existing structure of assembling the TO package shell and the main shell, the optical transceiver module of the present invention is conducive to airtight packaging and has better structural stability.

[0063] In addition, low-cost lithium niobate modulators are used to modulate optical signals, and the wavelength and bandwidth of the modulated optical signals meet the requirements of high-speed long-distance transmission. The combination of electro-absorption modulated lasers, direct modulated lasers and lithium niobate modulators is also conducive to adjusting the output power and extinction ratio of optical signals to meet the requirements of high-speed PON.

Claims

1. A single-fiber bidirectional multi-channel optical transceiver module, characterized in that: Include: A housing having a receiving cavity; A light emitting assembly is disposed in the accommodating cavity, and the light emitting assembly includes a plurality of light emitting units and a wavelength division multiplexer disposed corresponding to the plurality of light emitting units; A light receiving assembly is disposed in the accommodating cavity, and the light receiving assembly includes a plurality of light receiving units and a wavelength division multiplexer disposed corresponding to the plurality of light receiving units; as well as The optical fiber adapter is arranged on the housing.

2. The single-fiber bidirectional multi-channel optical transceiver module according to claim 1, characterized in that: The accommodating cavity is an independent single cavity.

3. The single-fiber bidirectional multi-channel optical transceiver module according to claim 1, characterized in that: The accommodating cavity is an airtight cavity.

4. The single-fiber bidirectional multi-channel optical transceiver module according to claim 1, characterized in that: The light emitting component further includes a lithium niobate modulator, and the lithium niobate modulator is disposed corresponding to at least one of the plurality of light emitting units.

5. The single-fiber bidirectional multi-channel optical transceiver module according to claim 4, characterized in that: The plurality of light emitting units include an electro-absorption modulated laser, a directly modulated laser and a continuous wavelength laser, and the lithium niobate modulator is arranged corresponding to the continuous wavelength laser.

6. The single-fiber bidirectional multi-channel optical transceiver module according to claim 1, characterized in that: The optical fiber further comprises a first optical path turning element, and the first optical path turning element is arranged between the optical fiber adapter and the wavelength division multiplexer of the optical transmitting component.

7. The single-fiber bidirectional multi-channel optical transceiver module according to claim 6, characterized in that: The first optical path turning element is a beam splitter prism, which changes the transmission direction of the optical signal input from the optical fiber adapter to be transmitted toward the optical receiving component, and allows the optical signal output from the optical transmitting component to pass through and be transmitted to the optical fiber adapter.

8. The single-fiber bidirectional multi-channel optical transceiver module according to claim 6, characterized in that: The invention further comprises a second light path turning element, and the second light path turning element is arranged at the light emitting end of the first light path turning element.

9. The single-fiber bidirectional multi-channel optical transceiver module according to claim 8, characterized in that: The second optical path turning element is a reflector, which changes the transmission direction of the optical signal output from the optical emitting end of the first optical path turning element to be transmitted toward the wavelength division multiplexer.

10. The single-fiber bidirectional multi-channel optical transceiver module according to claim 8, characterized in that: The first light path turning element and the second light path turning element are both disposed in the accommodating cavity.

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