A miniaturized single fiber bidirectional optical device

Abstract

The utility model relates to a kind of miniaturized single-fiber bidirectional optical devices, including optical fiber adapter, installation body and the emitting unit and photoelectric detector being set in installation body, emitting unit includes continuous wavelength laser, emitting light lens assembly and MZM modulator, continuous wavelength laser is used to emit to MZM modulator, optical fiber coupling lens and filter assembly are arranged between optical fiber adapter and photoelectric detector component, laser of emitting unit is emitted to optical fiber adapter by filter assembly and optical fiber coupling lens, optical fiber adapter emits laser and is emitted to photoelectric detector by optical fiber coupling lens and filter assembly.The utility model emits laser to optical fiber adapter by emitting unit, optical fiber adapter sends to photoelectric detector after receiving laser is output again, the continuous wavelength laser of the scheme used makes that output laser output power and light intensity are stable, the transmission rate and transmission length of optical fiber are all improved after the laser of MZM modulator processing.

Description

Technical Field

[0001] This utility model relates to the field of optical fiber communication technology, specifically to a miniaturized single-fiber bidirectional optical device. Background Technology

[0002] The function of single-fiber bidirectional optical devices is to enable bidirectional transmission of optical signals in the same optical fiber, eliminating the need to lay two separate optical fibers for transmission and reception, thus reducing fiber optic costs and simplifying cabling.

[0003] However, existing single-fiber bidirectional optical devices use a DML laser or EML laser as the entire transmitting unit. A photodetector receives an optical signal with a different wavelength from the emitted wavelength from a single optical fiber and converts it back into an electrical signal, such as... Figure 1 As shown. Due to its inherent structure, DML lasers exhibit significant chirp during use and are generally used for transmission rates below 25G and applications within 10km. EML lasers, on the other hand, can reach speeds of 50G and transmission lengths of up to 40km, but further increases are extremely difficult.

[0004] Existing single-fiber optical devices employ direct modulation, controlling the output optical power by directly changing the driving current injected into the laser. This is a low-cost and structurally simple modulation method, but it is also a major source of chirp. For example, DML lasers are directly modulated by current. The chirp generated by DML lasers is essentially due to the refractive index change caused by current modulation, leading to frequency drift. Furthermore, the chip's heating behavior varies under different currents, resulting in different refractive indices. EML lasers, on the other hand, use electroabsorption modulation. The chirp of EML lasers mainly originates from the physical characteristics of their internal electroabsorption modulator and carrier changes during the modulation process. Although smaller than the chirp of DML lasers, it still exists.

[0005] Therefore, the transmission distance of existing DML or EML lasers is affected by chirp, resulting in limited transmission rate and transmission length, which seriously affects the signal quality of high-speed optical communication. Utility Model Content

[0006] The first aspect of this invention aims to solve the technical problems of the limited transmission efficiency and transmission length in the prior art, and provides a miniaturized single-fiber bidirectional optical device that can improve the transmission rate and transmission length by introducing a continuous wavelength laser and an MZM modulator for processing the continuous laser.

[0007] To achieve the above objectives, this invention provides a miniaturized single-fiber bidirectional optical device, including an optical fiber adapter, a mounting body, and a transmitting unit and a photodetector disposed within the mounting body. The transmitting unit includes a continuous-wavelength laser, a transmitting lens assembly, and an MZM modulator. The continuous-wavelength laser is used to transmit light to the MZM modulator, and the transmitting lens assembly processes the laser from the transmitting unit into a parallel laser. An optical fiber coupling lens and a filtering assembly are disposed between the optical fiber adapter and the photodetector assembly. The laser from the transmitting unit is transmitted to the optical fiber adapter through the filtering assembly and the optical fiber coupling lens. The laser emitted by the optical fiber adapter is then transmitted to the photodetector through the optical fiber coupling lens and the filtering assembly. The laser is transmitted from the transmitting unit to the optical fiber adapter, and the optical fiber adapter outputs the received laser again before sending it to the photodetector. The continuous-wavelength laser used in this design ensures stable output power and intensity, and the laser processed by the MZM modulator improves both the transmission rate and transmission length of the optical fiber.

[0008] Preferably, the emitting lens assembly includes a collimating lens disposed at the emitting end of the continuous-wavelength laser. The collimating lens transforms the diverging laser emitted by the continuous-wavelength laser into a parallel laser, enabling the continuously emitted parallel laser to enter the MZM modulator.

[0009] The second aspect of this invention aims to solve the technical problem of excessively large package size after arranging a continuous wavelength laser and an MZM modulator. Furthermore, the transmitting unit also includes a reflecting assembly, which comprises a first reflecting mirror and a second reflecting mirror. The first reflecting mirror reflects the laser output from the collimating lens, and the second reflecting mirror receives the laser reflected by the first reflecting mirror. The first and second reflecting mirrors are arranged at a 45° angle to each other. This solution uses a 45° arranged reflecting mirror group, allowing the laser to be oriented and, after two right-angle reflections, output a reflected laser that remains parallel to the continuous laser output from the transmitting assembly. This enables the continuous laser transmitter and the MZM modulator to be arranged side-by-side and integrated on a small mounting platform, resulting in a compact and flexible package size.

[0010] Preferably, an isolator is provided between the collimating lens and the first reflecting mirror. The isolator prevents the reflected light after passing through the first reflecting mirror from entering the continuous wavelength laser in the opposite direction, which would cause the output of the continuous wavelength laser to be unstable.

[0011] Preferably, the emitting lens assembly further includes an MZM input coupling lens and an MZM output coupling lens. The MZM input coupling lens and the MZM output coupling lens are respectively positioned as the receiving end and output end of the MZM modulator. The MZM input coupling lens is used to receive the reflected laser light from the second reflector to the receiving end of the MZM modulator, and the MZM output coupling lens is used to receive the laser light output from the output end of the MZM modulator. Both the laser light entering and exiting the MZM modulator are processed by the emitting lens assembly, ensuring that the laser light remains parallel throughout its propagation.

[0012] Preferably, the mounting body includes a casing and a non-hermetic chamber. The casing seals the transmitting unit, and the non-hermetic chamber houses the filter assembly, photodetector, and fiber optic adapter. Gold-plated pins are located on the sidewall of the casing to facilitate gold wire bonding of the transmitting unit inside the casing, thereby powering the devices within the casing.

[0013] The third aspect of this invention aims to solve the technical problem of poor heat dissipation in existing laser components, which affects laser performance. Furthermore, a semiconductor cooler is provided within the packaging box, and the semiconductor cooler is used to house the emitting unit. By using a semiconductor cooler for cooling and employing tungsten copper, a metal with excellent thermal conductivity, heat dissipation performance is further improved.

[0014] Preferably, the filtering component includes a 45° filter and a 2° filter, with the 45° filter positioned below the 2° filter and a photodetector positioned above the 2° filter. Since the transmitting wavelength of the transmitting unit and the receiving wavelength of the fiber optic adapter are different, the 45° filter allows the laser light from the transmitting end to pass through while reflecting the laser light emitted from the fiber optic adapter to the photodetector. The 2° filter isolates the light from the transmitting end, allowing only the light of the receiving wavelength to pass through, thus completing the path from the transmitting unit to the fiber optic adapter, and from the fiber optic adapter to the photodetector.

[0015] The fourth aspect of this invention aims to solve the technical problem of large package size of existing photodetectors. Furthermore, the fiber optic coupling lens is disposed between the filter assembly and the fiber optic adapter. In the prior art, to match the laser beam with the photodetector interface, the fiber optic coupling lens is placed at the receiving end of the photodetector. To allow for a convergence distance, a distance needs to be maintained between the fiber optic coupling lens and the photodetector, which increases the working distance and makes the photodetector's package size too large. In this solution, the fiber optic coupling lens is disposed between the fiber optic adapter and the filter assembly, so that the laser emitted from the MZM modulator enters the filter assembly, first undergoes coupling and convergence at the fiber optic coupling lens, and then passes through the filter assembly.

[0016] The beneficial effects of this utility model are as follows:

[0017] The laser is emitted by the transmitting unit to the fiber optic adapter, which then outputs the received laser to the photodetector. The continuous wavelength laser used in this scheme ensures stable output power and intensity. The laser processed by the MZM modulator improves both the transmission rate and transmission length of the optical fiber. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the existing technology.

[0019] Figure 2 This is a schematic diagram of the structure of this utility model.

[0020] Figure 3 This is a cross-sectional view of the structure of this utility model.

[0021] Figure 4 This is an internal structural diagram of the present invention.

[0022] Figure 5 This is a schematic diagram of the transmitter of this utility model.

[0023] Figure 6 This is a schematic diagram of the receiver of this utility model.

[0024] The reference numerals in the accompanying drawings include: 1. Continuous wavelength laser; 2. MZM modulator; 3. Emitting light lens assembly; 31. Collimating lens; 32. MZM input coupling lens; 33. MZM output coupling lens; 4. Mounting body; 41. Encapsulation box; 42. Non-hermetic chamber; 43. Semiconductor cooler; 5. Fiber optic coupling lens; 6. Fiber optic adapter; 7. Isolator; 8. Reflection assembly; 81. First reflector; 82. Second reflector; 9. Filtering assembly; 91. 45° filter; 92. 2° filter; 10. Photodetector. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0026] In this disclosure, unless otherwise stated, directional terms such as "inner" and "outer" are defined based on the contours of the corresponding components. Terms such as "first" and "second" used in this disclosure are for distinguishing one element from another and do not imply sequence or importance.

[0027] like Figures 2-6 As shown, this embodiment provides a miniaturized single-fiber bidirectional optical device, including an optical fiber adapter 6, a mounting body 4, and a transmitting unit and a photodetector 10 disposed within the mounting body 4. The transmitting unit includes a continuous-wavelength laser 1, a transmitting light lens assembly 3, and an MZM modulator 2. The continuous-wavelength laser 1 is used to transmit light to the MZM modulator 2, and the transmitting light lens assembly 3 processes the laser from the transmitting unit into a parallel laser. An optical fiber coupling lens 5 and a filter assembly 9 are disposed between the optical fiber adapter 6 and the photodetector 10 assembly. The laser from the transmitting unit is transmitted to the optical fiber adapter 6 through the filter assembly 9 and the optical fiber coupling lens 5, and the laser emitted by the optical fiber adapter 6 is transmitted to the photodetector 10 through the optical fiber coupling lens 5 and the filter assembly 9. The laser is transmitted from the transmitting unit to the optical fiber adapter 6, and the optical fiber adapter 6 outputs the received laser again and sends it to the photodetector 10. The continuous-wavelength laser 1 used in this scheme ensures stable output power and intensity of the laser, and the laser processed by the MZM modulator 2 improves both the transmission rate and transmission length of the optical fiber.

[0028] The emitting lens assembly 3 includes a collimating lens 31, which is disposed at the emitting end of the continuous wavelength laser 1. The collimating lens 31 transforms the divergent laser emitted by the continuous wavelength laser 1 into a parallel laser, enabling the continuously emitted parallel laser to enter the MZM modulator 2.

[0029] like Figure 6 As shown, to address the technical issue of excessively large package size after arranging the continuous wavelength laser 1 and MZM modulator 2, the transmitting unit further includes a reflecting assembly 8. The reflecting assembly 8 comprises a first reflecting mirror 81 and a second reflecting mirror 82. The first reflecting mirror 81 reflects the laser output from the collimating lens 31, and the second reflecting mirror 82 receives the laser reflected by the first reflecting mirror 81. The first reflecting mirror 81 and the second reflecting mirror 82 are arranged at a 45° angle to each other. This scheme uses a 45° arrangement of reflecting mirrors, allowing the laser to be oriented and, after two right-angle reflections, output a reflected laser that remains parallel to the continuous laser output from the transmitting assembly. This enables the continuous laser transmitter and MZM modulator 2 to be arranged side-by-side and integrated on a small mounting platform, resulting in a compact and flexible package size.

[0030] like Figure 4 As shown, an isolator 7 is provided between the collimating lens 31 and the first reflecting mirror 81. The isolator 7 can prevent the reflected light after passing through the first reflecting mirror 81 from entering the continuous wavelength laser 1 in the opposite direction, which would cause the output of the continuous wavelength laser 1 to be unstable.

[0031] like Figure 2 -like Figure 5 As shown, the emitting lens assembly 3 also includes an MZM input coupling lens 32 and an MZM output coupling lens 33. The MZM input coupling lens 32 and the MZM output coupling lens 33 are respectively positioned at the receiving end and output end of the MZM modulator 2. The MZM input coupling lens 32 receives the reflected laser light from the second reflector 82 to the receiving end of the MZM modulator 2, and the MZM output coupling lens 33 receives the laser light output from the output end of the MZM modulator 2. Both the laser light entering and exiting the MZM modulator 2 are processed by the emitting lens assembly 3, ensuring that the laser light remains parallel throughout its propagation.

[0032] In the specific implementation process, the receiving end and the output end of the MZM modulator 2 in this embodiment are set on the same side, which facilitates the adjustment of the relative positions of the MZM input coupling lens 32 and the MZM output coupling lens 33.

[0033] like Figures 2-3 As shown, the mounting body 4 includes a casing 41 and a non-airtight chamber 42. The casing 41 is used to seal the transmitting unit, and the non-airtight chamber 42 houses the filter assembly 9, the photodetector 10, and the fiber optic adapter 6. Gold-plated pins are located on the sidewall of the casing 41, facilitating gold wire bonding of the transmitting unit inside the casing 41 to power the devices within the casing 41.

[0034] To address the technical problem of poor heat dissipation in existing laser components, which negatively impacts laser performance, this embodiment incorporates a semiconductor cooler 43 within the encapsulation box 41. The semiconductor cooler 43 houses the emitting unit. By utilizing the semiconductor cooler 43 for cooling and employing tungsten copper, a metal with excellent thermal conductivity, heat dissipation performance is further enhanced.

[0035] like Figures 3-6 As shown, the filtering component 9 includes a 45° filter 91 and a 2° filter 92. The 45° filter 91 is positioned below the 2° filter 92, and the photodetector 10 is positioned above the 2° filter 92. Since the transmitting wavelength of the transmitting unit and the receiving wavelength emitted by the fiber optic adapter 6 are different, the 45° filter 91 allows the laser light from the transmitting end to pass through, while reflecting the laser light emitted from the fiber optic adapter 6 to the receiving end of the photodetector 10. The 2° filter 92 isolates the light from the transmitting end, allowing only the light of the receiving wavelength to pass through, thus completing the path from the transmitting unit to the fiber optic adapter 6, and from the fiber optic adapter 6 to the photodetector 10.

[0036] In the non-airtight chamber 42 of the mounting body, the 45° filter 91 and the 2° filter 92 are stably installed by means of a bracket.

[0037] like Figures 5-6As shown, the collimating lens 31 of the emitting light lens assembly 3 can convert the received divergent light into a parallel beam. After the parallel beam is incident on the optical isolator 7, it is reflected by the first reflector 81 and the second reflector 82, and then converted into a converging light by the MZM input coupling lens 32, the MZM output coupling lens 33 and the fiber coupling lens 5, and coupled into the fiber of the fiber adapter 6.

[0038] To address the technical problem of large package size of the existing photodetector 10, the fiber optic coupling lens 5 is disposed between the filter component 9 and the fiber optic adapter 6.

[0039] In existing technologies, to match the laser beam with the interface of the broadcast detector, the fiber optic coupling lens 5 is placed at the receiving end of the photodetector 10. In order to reserve the convergence distance, a distance needs to be left between the fiber optic coupling lens 5 and the photodetector 10, which makes the working distance longer and the packaging volume of the photodetector 10 too large. In this solution, the fiber optic coupling lens 5 is placed between the fiber optic adapter 6 and the filter assembly, so that the laser emitted by the MZM modulator 2 enters the filter assembly and is first coupled and converged by the fiber optic coupling lens 5 before passing through the filter assembly.

[0040] In this embodiment, the receiving end of the photodetector 10 adopts a TO sealing scheme. The receiving end of the photodetector 10 and the transmitting end of the transmitting unit are not in the same sealed cavity, which can reduce crosstalk.

[0041] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A miniaturized single-fiber bidirectional optical device, characterized in that: The device includes an optical fiber adapter, a mounting body, and a transmitting unit and a photodetector disposed within the mounting body. The transmitting unit includes a continuous wavelength laser, a transmitting light lens assembly, and an MZM modulator. The continuous wavelength laser is used to transmit light to the MZM modulator, and the transmitting light lens assembly processes the laser light from the transmitting unit into parallel laser light. An optical fiber coupling lens and a filtering assembly are disposed between the optical fiber adapter and the photodetector assembly. The laser light from the transmitting unit is transmitted to the optical fiber adapter through the filtering assembly and the optical fiber coupling lens, and the laser light emitted by the optical fiber adapter is transmitted to the photodetector through the optical fiber coupling lens and the filtering assembly.

2. The miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The light-emitting lens assembly includes a collimating lens, which is disposed at the emitting end of the continuous wavelength laser.

3. A miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The transmitting unit further includes a reflecting component, which includes a first reflecting mirror and a second reflecting mirror. The first reflecting mirror is used to reflect the laser output from the collimating lens, and the second reflecting mirror is used to receive the laser reflected by the first reflecting mirror. The first reflecting mirror and the second reflecting mirror are arranged at 45° relative to each other.

4. A miniaturized single-fiber bidirectional optical device according to claim 3, characterized in that: An isolator is provided between the collimating lens and the first reflecting mirror.

5. A miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The emitting light lens assembly further includes an MZM input coupling lens and an MZM output coupling lens. The MZM input coupling lens and the MZM output coupling lens are respectively set as the receiving end and the output end of the MZM modulator. The MZM input coupling lens is used to receive the reflected laser from the second reflector to the receiving end of the MZM modulator, and the MZM output coupling lens is used to receive the laser output from the output end of the MZM modulator.

6. A miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The mounting body includes a sealing box and a non-airtight chamber. The sealing box is used to seal the transmitting unit, and the non-airtight chamber is used to install the filter assembly, photodetector, and fiber optic adapter.

7. A miniaturized single-fiber bidirectional optical device according to claim 6, characterized in that: The encapsulation box contains a semiconductor cooler, which is used to house the transmitting unit.

8. A miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The filtering component includes a 45° filter and a 2° filter, with the 45° filter positioned below the 2° filter and a photodetector positioned above the 2° filter.

9. A miniaturized single-fiber bidirectional optical device according to claim 1, characterized in that: The fiber optic coupling lens is positioned between the filter assembly and the fiber optic adapter.

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