OTDR (Optical Time Domain Reflectometer) optical module capable of eliminating blind area at initial section of optical fiber

Abstract

The utility model discloses an OTDR (Optical Time Domain Reflectometer) optical module capable of eliminating a blind area at an initial section of an optical fiber. The OTDR optical module comprises an upper shell, a lower shell, a frame, a PCBA (Printed Circuit Board Assembly), the optical fiber and an electric connector, wherein the frame is installed between the upper shell and the lower shell, the middle of the frame is open to form a window, and a fiber coiling ring is formed on the top surface of the frame and surrounds the periphery of the window; the PCBA board is installed on the bottom face of the frame, and the electric device, the optical device and the lens unit which are installed on the PCBA board are located in the area of the window. After the optical fiber is butted with the lens unit, a section of optical fiber is wound on the fiber winding ring to form an internal fiber winding and then is led out of the upper shell; the internal coiled fiber is longer than the blind area of the optical fiber initial section; the electric connector is installed on the lower shell, serves as an electric interface and a data interface of the optical module and is electrically connected with the PCBA board. According to the utility model, the internal disc fiber is additionally arranged in the optical module, and the blind area of the initial section of the optical fiber is positioned in the internal disc fiber, so that the problem that a section of optical fiber behind the starting point of the optical fiber cannot be subjected to OTDR detection is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical fiber communication, and specifically relates to an optical module used in an optical fiber network. Background Art

[0002] With the continuous development and large-scale application of optical fiber communication technology, the complexity of optical fiber networks is increasing. In actual use, optical modules with integrated OTDR (optical time domain reflectometer) functions can locate and diagnose breakpoint events of optical fiber links, thereby facilitating the troubleshooting and maintenance of optical fiber network connection status.

[0003] In the process of locating and diagnosing event points of optical fiber links, the existing OTDR optical module usually adopts the following method: an OTDR optical pulse is emitted into the optical fiber link; when the OTDR optical pulse propagates in the optical fiber link, when it encounters event points such as optical fiber connections, breaks, defects, end faces, and tail ends, Fresnel reflection occurs to generate a back-reflected signal, and at the same time, Rayleigh scattering is caused by the uneven particles in the optical fiber material, generating a back-scattered signal; the back-reflected and scattered signals return to the OTDR optical module via the optical fiber link and enter the OTDR detector inside the optical module. After the OTDR detector performs photoelectric conversion, an electrical signal that can reflect the light intensity is generated, which is sent to the OTDR processing circuit for amplification, shaping, filtering, high-speed analog-to-digital conversion, etc., to obtain the back-reflected signal strength data that varies with time. According to the data, an OTDR test curve can be generated to determine the location and type of the fault point of the optical fiber link.

[0004] The problem with this type of OTDR optical module is that Fresnel reflection is generated at the starting end face of the optical fiber (the interface between air and optical fiber). The intensity of the backward Fresnel reflected optical signal is relatively large, which can easily cause saturation of the OTDR detector. It takes some time for the OTDR detector to go from saturation to being able to perform tests. During this time, the optical module will not be able to perform OTDR detection, resulting in a section of optical fiber after the starting point being unable to perform fault diagnosis. This section of optical fiber is called the blind area of ​​the initial section of the optical fiber.

[0005] For multimode fiber links for short-distance communication, since the optical fiber connecting the optical module is relatively short, usually tens of centimeters, and the optical fiber link at the initial end often has multiple connector transfers, this section of optical fiber becomes a location prone to failure in the multimode fiber network. Therefore, it is very necessary to detect the initial section of optical fiber connected to the optical module. Utility Model Content

[0006] The utility model aims to provide an OTDR optical module which can eliminate the blind area of ​​the initial section of optical fiber. By adding an internal fiber coil in the optical module, the blind area of ​​the initial section of optical fiber is positioned in the internal fiber coil, thereby solving the problem that a section of optical fiber after the starting point of the optical fiber cannot be detected by OTDR.

[0007] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0008] An OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber, comprising:

[0009] upper and lower shells;

[0010] A frame is installed between the upper shell and the lower shell, with a window opened in the middle, and a fiber ring is formed on the top surface of the frame around the periphery of the window;

[0011] A PCBA board is mounted on the bottom surface of the frame, and electrical components, optical components and a lens unit are mounted on the board; the electrical components, optical components and lens unit are located in the area of ​​the window;

[0012] The optical fiber, after being docked with the lens unit, is coiled on the fiber coiling ring for a section to form an internal fiber coil, and then is led out of the upper shell; the length of the internal fiber coil is greater than the length of the blind area of ​​the initial section of the optical fiber;

[0013] The electrical connector is mounted on the lower shell and serves as an electrical interface and a data interface of the optical module and is electrically connected to the PCBA board.

[0014] In some embodiments of the present application, in order to facilitate the winding of the optical fiber inside the optical module, the fiber winding ring can be configured to be two arc portions, and the two arc portions are arranged opposite to each other and spaced apart. In this way, after the optical fiber is docked with the lens unit, it can be led out of the window from the gap between the two arc portions, and then coiled on the outside of the two arc portions.

[0015] In some embodiments of the present application, a top baffle extending outward may be formed on the top surface of the two arc portions or in the middle area of ​​the top surface to prevent the internal disk fibers from axially loosening.

[0016] In some embodiments of the present application, two stop frames can be set on the top surface of the frame; the two stop frames are configured to be located at the edge positions of the top surface of the frame and respectively correspond to the positions of two spacing areas formed between the two arc portions; the internal fiber coil is coiled on the outside of the two arc portions and on the inside of the two stop frames to prevent the internal fiber coil from loosening radially.

[0017] In some embodiments of the present application, an adjustment groove can be set at the edge position of the top surface of the frame. After the optical fiber passes through the adjustment groove, it is led out from the optical fiber lead-out hole opened on the upper shell to form a pigtail. The free end of the pigtail can be installed with an optical interface, and the optical module is connected to the optical fiber network through the optical interface; a protective sleeve is installed on the section of the optical fiber passing through the adjustment groove, and a tensile flange is installed on the protective sleeve. The tensile flange is installed in the adjustment groove, and the length of the pigtail is adjusted by adjusting the position of the protective sleeve on the pigtail and the position of the tensile flange in the adjustment groove to meet various customized needs of customers.

[0018] In some embodiments of the present application, in order to improve the heat dissipation effect of the optical module, the upper shell, frame and lower shell can be made of metal materials, and after being assembled together, the four peripheries of the frame are exposed, and the PCBA board is attached to the bottom surface of the frame. In this way, the heat generated by the PCBA board can be quickly conducted away through the metal frame to expand the temperature resistance range of the optical module.

[0019] In some embodiments of the present application, in order to further improve the heat dissipation effect of the optical module, a thermally conductive sealant can be filled in the window area of ​​the frame, and the top surface of the thermally conductive sealant can be fitted with the upper shell. In this way, the heat generated by the electrical and optical components on the PCBA board can be quickly conducted away through the thermally conductive sealant and the metal upper shell, so as to form an optical module with a wide temperature range and high reliability.

[0020] In some embodiments of the present application, an assembly opening that is compatible with the outer contour of the electrical connector can be opened on the lower shell, the electrical connector can be embedded in the assembly opening, and positioning holes can be opened on the electrical connector and the PCBA board respectively, and guide pins can be installed in the positioning holes. The guide pins can limit the installation position of the electrical connector, so that the metal spring sheet on the electrical connector can be in fixed-point contact with the PCBA board to ensure accurate electrical connection between the electrical connector and the PCBA board.

[0021] In some embodiments of the present application, in order to ensure the continuity of high-speed optical signal transmission to meet the high-speed communication requirements of multi-mode optical fiber networks, a support foot can be formed on the bottom surface of the lens unit, the lens unit can be mounted on the PCBA board through the support foot, and a gap can be formed between the bottom surface of the lens unit and the PCBA board; the optical device is arranged in the gap below the lens unit to shorten the distance between the optical device and the lens unit as much as possible, which is conducive to the miniaturization design of the optical module while reducing interference.

[0022] Compared with the prior art, the advantages and positive effects of the utility model are mainly reflected in:

[0023] The utility model arranges a fiber coil inside the optical module, and the length of the fiber coil is greater than the length of the blind zone of the initial section of the optical fiber. In this way, even if Fresnel reflection occurs at the starting end face of the optical fiber, the optical fiber in the blind zone is inside the optical module, and the optical module output pigtail and the optical fiber link connected thereto can be accurately detected, thereby solving the problem that the optical module pigtail and the optical cable connected thereto cannot be detected due to the blind zone of the initial section of the optical fiber.

[0024] 2. For pigtail optical modules, by setting a fiber coil inside the optical module, the fiber pigtail length of the optical module can be adjusted by adjusting the fiber coil length to meet the various customized needs of different customers, thereby expanding the versatility of the pigtail optical module.

[0025] 3. The optical module of the utility model is particularly suitable for use in optical fiber links in the field of data center communications and special optical network applications to solve the problems of daily management, maintenance and detection of optical fiber networks in this field.

[0026] After reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a diagram of the overall appearance of an embodiment of an OTDR optical module proposed by the utility model that can eliminate the blind area of ​​the initial section of the optical fiber;

[0029] Figure 2 yes Figure 1 An exploded view of the structure of an embodiment of the optical module shown;

[0030] Figure 3 yes Figure 2 A schematic structural diagram of an embodiment of an upper shell in FIG.

[0031] Figure 4 yes Figure 3 A bottom view of the upper shell is shown;

[0032] Figure 5 yes Figure 2 A schematic diagram of a structure of an embodiment of the framework in;

[0033] Figure 6 yes Figure 5 a bottom view of the frame shown;

[0034] Figure 7 yes Figure 2 A structural schematic diagram of an embodiment of a PCBA board;

[0035] Figure 8 yes Figure 2 A schematic structural diagram of an embodiment of an optical fiber assembly;

[0036] Fig. 9 yes Figure 2 A schematic structural diagram of an embodiment of a lower shell in FIG.

[0037] Fig.10 yes Figure 2 A structural schematic diagram of an embodiment of an electrical connector;

[0038] Fig.11 It is a schematic diagram of the installation structure of the light emitting lens unit on the PCBA board;

[0039] Fig.12 It is a schematic diagram of the installation structure of the light receiving lens unit on the PCBA board. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0041] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", "middle", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the present invention.

[0042] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances. In the description of the implementation method, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0043] In the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0044] See also Figure 1 , Figure 2 The optical module of this embodiment mainly includes an upper shell 10, a frame 20, a lower shell 30, an electrical connector 40, a PCBA board 50, an optical fiber assembly 60 and other components. The upper shell 10, the frame 20, the lower shell 30 and the electrical connector 40 are assembled together to form an external shell 100 of the optical module, and the pigtail part 62 of the optical fiber assembly 60 is led out from the external shell 100 and connected to the optical interface (optical connector) 70.

[0045] In some embodiments, the upper shell 10 can be designed as a box structure with an open bottom, such as Figure 3 , Figure 4 As shown, it includes a top surface 11 and surrounding sides 12. An area 13 for pasting product logos can be formed on the outer side of the top surface 11, and a plurality of connection seats 15 can be arranged on the inner side of the top surface 11. The connection seats 15 are provided with threaded holes 16 for threaded connection with the frame 20 and the lower shell 30 through screws 17.

[0046] A fiber lead-out hole 14 may be provided on one of the circumferential sides 12 of the upper shell 10 , and the pigtail portion 62 of the optical fiber assembly 60 may pass through the fiber lead-out hole 14 and out of the outer shell 100 of the optical module.

[0047] In some embodiments, the outer contour size of the frame 20 can be designed to be compatible with the upper shell 10, so that after the frame 20 is assembled with the upper shell 10 and the lower shell 30, the four peripheries of the frame 20 can be exposed. In this way, after the PCBA board 50 is installed on the frame 20, the heat generated by the PCBA board 50 can be directly released to the outside through the frame 20 to improve the heat dissipation effect of the optical module.

[0048] In order to make the PCBA board 50 fit closely with the frame 20 to speed up the heat conduction, Figure 2 , Figures 5 to 8 As shown, the middle area of ​​the frame 20 can be designed to be open to form a window 21 to avoid the electrical components, optical components and lens units on the PCBA board 50. A mounting surface 26 adapted to the outer contour of the PCBA board 50 can be formed on the bottom surface of the frame 20, and screw holes 25 and 55 can be opened at corresponding positions of the frame 20 and the PCBA board 50. Figure 6 , Figure 7 As shown, the PCBA board 50 is fixed to the bottom surface of the frame 20 by screws 18 and is closely fitted to the mounting surface 26 to increase the heat conduction area. In this way, the electrical components, optical components and lens units on the PCBA board 50 can be exposed to the top surface of the frame 20 through the window 21.

[0049] A fiber coil ring 22 can be installed at the top surface of the frame 20 around the window 21, for winding the optical fiber thereon to form an internal fiber coil 61. The length of the internal fiber coil 61 is configured to be greater than the length of the blind area of ​​the initial section of the optical fiber, so that the positions of all event points and accurate backward light intensity data can be obtained during OTDR detection.

[0050] In some embodiments, the fiber ring 22 may be designed to consist of two arc portions 221 and 222. Figure 5 As shown, the two arc portions 221 , 222 are disposed opposite to each other and separated headwardly and tailwardly to form two spacing areas 23 , 24 .

[0051] Each arc portion 221 / 222 may include a vertical winding surface 223 and a horizontal top baffle 224. Figure 2 The top baffle 224 is disposed on the top of the winding surface 223 and extends outward, and may cover the entire top of the winding surface 223, or may only cover the middle area of ​​the top of the winding surface 223, so as to prevent the optical fiber wound on the winding surface 223 from axially loosening, that is, from detaching from the fiber coiling ring 22 from above.

[0052] In order to prevent the optical fiber wound on the winding surface 223 from radially loosening, a stop frame 27 can be set at the edge of the top surface of the frame 20. For example, a stop frame 27 can be set on the opposite sides of the top surface of the frame 20, and the positions of the two stop frames 27 are preferably corresponding to the positions of the two spacing areas 23 and 24 formed between the two arc portions 221 and 222, so as to improve the limiting effect of the internal fiber coil 61.

[0053] In this embodiment, the stop frame 27 can be designed to be long and protruding from the top surface of the frame 20 and at the same height as the fiber coil ring 22. The inner side surface of the stop frame 27 (the side surface adjacent to the internal fiber coil 61) can be designed to be an inner concave arc surface to provide more margin for adjusting the diameter of the internal fiber coil 61.

[0054] An adjustment groove 80 is also provided at the edge of the top surface of the frame 20. Figure 2 , Figure 5 The arrangement position of the adjustment groove 80 should correspond to the position of the optical fiber lead-out hole 14 opened on the upper shell 10, for example, be arranged at the same corner position to guide the optical fiber to be led out of the outer shell 100 of the optical module from this position.

[0055] In some embodiments, some optical modules use two lens units to respectively complete the transmission and reception of optical signals, such as a light transmission and detection lens unit 51 and a light receiving lens unit 52. Figure 2 , Figure 6 , Figure 7As shown. The optical emission and detection lens unit 51 is connected to the transmitting optical fiber 69, and is used to focus the communication optical signal and OTDR optical pulse generated by the user end and then inject them into the transmitting optical fiber 69, and receive the back reflection and scattered signals returned by the transmitting optical fiber 69. The optical receiving lens unit 52 is connected to the receiving optical fiber 63, and is used to receive the opposite communication optical signal from the opposite end.

[0056] After one end of the transmitting optical fiber 69 is connected to the optical transmitting and detecting lens unit 51, the window 21 can be led out through one of the spacing areas 24 formed by the two arc sections of the fiber coiling ring 22, and then coiled outside the two arc sections 221 and 222. After one end of the receiving optical fiber 63 is connected to the optical receiving lens unit 52, the window 21 can be led out through another spacing area 23 formed by the two arc sections of the fiber coiling ring 22, and then coiled outside the two arc sections 221 and 222. The transmitting optical fiber 69 and the receiving optical fiber 63 are wound around the fiber coiling ring 22 for one or more turns (the number of turns can be determined comprehensively according to the length of the blind area of ​​the initial section of the optical fiber and the length requirement of the pigtail), and after forming the internal fiber coil 61, they pass through the adjustment groove 80 together, and then extend through the optical fiber lead-out hole 14 of the upper shell 10 to form the pigtail 62. Finally, the free end of the pigtail 62 is connected to the optical interface 70, so as to connect the optical module to the optical fiber link.

[0057] In certain embodiments, in combination Figure 2 , Figure 5 , Figure 8 As shown, the adjustment groove 80 can be designed to be a long strip, with the two sides 81 in the optical fiber routing direction being concave or flush with the top surface of the frame 20, and the other two sides 82 being convex and retracted inward at both ends to limit the tensile flange 64 installed on the optical fiber within the adjustment groove 80.

[0058] A protective sleeve 65 can be installed at the section of the optical fiber leaving the fiber coiling ring 22, and the tensile flange 64 can be installed on the protective sleeve 65 to avoid direct contact between the tensile flange 64 and the optical fiber, thereby protecting the optical fiber and achieving reliable bending of the optical fiber.

[0059] In actual use, the number of fiber coils inside the optical module can be adjusted according to various customized needs of users, and the manufacturing tolerance of the optical module pigtail 62 can be eliminated by adjusting the position of the protective sleeve 65 on the pigtail 62 and the position of the tensile flange 64 in the adjustment groove 80. After adjusting the length of the pigtail to meet the tolerance requirements, the length of the pigtail 62 can be fixed by applying structural glue between the tensile flange 64 and the adjustment groove 80. Applying this structure to the pigtail optical module can realize the free adjustment of the pigtail length, and the adjustment length can reach several centimeters, thereby reducing the processing difficulty of the pigtail optical module and expanding the versatility of the pigtail optical module.

[0060] Screw holes 28, 56, and 32 can be respectively opened at corresponding positions of the frame 20, the PCBA board 50, and the lower shell 30, which are assembled together by screws 17 and threadedly connected with the threaded holes 16 of the upper shell 10. After the PCBA board 50 is installed on the frame 20, a thermal conductive sealant can be further poured at the position of the window 21, and the top surface of the thermal conductive sealant is made to fit with the upper shell 10 to improve the sealing and heat dissipation performance of the optical module.

[0061] In some embodiments, a screw mounting hole 29 may be provided on the bottom surface of the frame 20. The screw mounting hole 29 may be designed as a threaded blind hole, and avoidance areas 57 and 33 may be formed at corresponding positions of the PCBA board 50 and the lower shell 30. Thus, when in use, the optical module may be fixed to other structural parts by screws to ensure that the optical module can withstand mechanical shocks caused by severe external vibrations.

[0062] In order to ensure that the PCBA board 50 is accurately installed on the bottom surface of the frame 20, a positioning column 66 can be set on the bottom surface of the frame 20, and a positioning hole 58 can be set at a corresponding position of the PCBA board 50. Figure 6 , Figure 7 During installation, first insert the positioning column 66 into the positioning hole 58 to determine the installation position of the PCBA board 50 on the frame 20, and then tighten it with the screw 17.

[0063] The lower shell 30 is installed below the PCBA board 50 so that the PCBA board 50 is closely attached to the lower shell 30 , and the upper shell 10 , the frame 20 , and the lower shell 30 are all made of metal materials to obtain the best heat dissipation effect.

[0064] like Fig. 9 As shown, an assembly opening 31 may be opened in the middle area of ​​the lower shell 30 , and the shape of the assembly opening 31 may be configured to match the outer contour of the electrical connector 40 , so as to facilitate the electrical connector 40 to be embedded in the assembly opening 31 of the lower shell 30 .

[0065] like Fig.10 As shown, the electrical connector 40 serves as the electrical interface and data interface of the optical module, and is provided with a metal spring 41 for contacting the PCBA board 50 at a fixed point to achieve electrical connection.

[0066] In order to ensure that the electrical connector 40 is installed accurately, positioning holes 42 and 59 can be respectively opened at corresponding positions of the electrical connector 40 and the PCBA board 50, and guide pins 19 can be inserted. Figure 2 As shown, to limit the relative position of the two.

[0067] In order to realize the miniaturized design of the optical module, in this embodiment, the lens units 51 and 52 are directly mounted on the PCBA board 50 to reduce the package size.

[0068] Specifically, if Fig.11 As shown, a foot 53 can be formed on the bottom surface of the light emitting and detecting lens unit 51, and the light emitting and detecting lens unit 51 is installed on the PCBA board 50 through the foot 53, and a gap 67 is formed between the bottom surface of the light emitting and detecting lens unit 51 and the PCBA board 50. The optical device in the optical module for generating communication optical signals and OTDR optical pulses, namely, a laser unit 71, and the optical device for receiving the back reflection and scattered signals generated by the OTDR optical pulses transmitted in the optical fiber link and performing photoelectric conversion, namely, an OTDR detector 72, are installed below the light emitting and detecting lens unit 51 and are located in the gap 67. In this way, not only can the space occupied by the optical device on the PCBA board 50 be reduced, so as to reduce the size of the PCBA board 50 and optimize the packaging design of the optical module; moreover, since the distance between the lens unit and the optical device is extremely close, the continuity of high-speed optical signal transmission can be guaranteed, and then the high-speed communication requirements of the multimode optical fiber network can be met.

[0069] Similarly, if Fig.12 As shown, a foot 54 can be formed on the bottom surface of the light receiving lens unit 52, and the light receiving lens unit 52 is mounted on the PCBA board 50 through the foot 54, and a gap 68 is formed between the bottom surface of the light receiving lens unit 52 and the PCBA board 50. The optical device in the optical module for receiving the opposite communication optical signal sent by the opposite end and performing photoelectric conversion, that is, the communication signal detector 73, is installed below the light receiving lens unit 52 and is located in the gap 68. While ensuring the continuity of high-speed optical signal transmission, the space occupation of the PCBA board 50 is reduced, which meets the design requirements of miniaturization of the optical module.

[0070] Of course, some electrical components may also be arranged in the gaps 67 and 68 formed by the lens unit and the PCBA board 50 , so that the size of the PCBA board 50 can be reduced as much as possible.

[0071] In order to solve the blind spot problem of the initial section of the optical fiber, this embodiment forms a section of coiled fiber inside the optical module. Therefore, when using OTDR technology to calculate the position of the event point in the optical fiber link, the length of the internal coiled fiber should be subtracted to correct the position of the event point, thereby eliminating the influence of the internal coiled fiber on the calculation result and ensuring the accuracy of the event point positioning.

[0072] The optical module of this embodiment has a small package size, light weight, good heat dissipation performance, and a temperature range of -40°C to 85°C, and can be used in special fields with harsh temperature environments. Applying it in a multimode optical fiber link for short-distance communication can eliminate the blind area of ​​the initial segment of the optical fiber and achieve accurate positioning of the initial event point.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the above embodiments, or to replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. An OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber, characterized in that: include: upper and lower shells; A frame is installed between the upper shell and the lower shell, with a window opened in the middle, and a fiber ring is formed on the top surface of the frame around the periphery of the window; A PCBA board is mounted on the bottom surface of the frame, and electrical components, optical components and a lens unit are mounted on the board; the electrical components, optical components and lens unit are located in the area of ​​the window; The optical fiber, after being connected to the lens unit, is coiled on the fiber coiling ring for a section to form an internal fiber coil, and then is led out of the upper shell; the length of the internal fiber coil is greater than the length of the blind area of ​​the initial section of the optical fiber; The electrical connector is mounted on the lower shell and serves as an electrical interface and a data interface of the optical module and is electrically connected to the PCBA board.

2. The OTDR optical module capable of eliminating the blind area of ​​the initial section of the optical fiber according to claim 1, characterized in that: The fiber coil ring comprises two arc sections, which are arranged opposite to each other and at intervals; After the optical fiber is connected to the lens unit, the window is led out from the interval area between the two arc parts and coiled outside the two arc parts.

3. The OTDR optical module capable of eliminating the blind area of ​​the initial section of the optical fiber according to claim 2, characterized in that: A top baffle extending outward is formed on the top surface of the two arc portions or in the middle area of ​​the top surface.

4. The OTDR optical module capable of eliminating the blind area of ​​the initial section of the optical fiber according to claim 2, characterized in that: Two stop frames are arranged on the top surface of the frame; The two stop frames are located at the edge of the top surface of the frame and correspond to the positions of the two interval areas formed between the two arc portions respectively; The internal fiber coil is located outside the two arc portions and inside the two stop frames.

5. The OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber according to claim 1, characterized in that: An adjustment groove is provided at the edge of the top surface of the frame, and after the optical fiber passes through the adjustment groove, it is led out from the optical fiber lead-out hole opened on the upper shell to form a pigtail; A protective sleeve is installed at a section of the optical fiber passing through the adjustment groove, and a tensile flange is installed on the protective sleeve. The tensile flange is installed in the adjustment groove. The position of the protective sleeve on the optical fiber and the position of the tensile flange in the adjustment groove are adjusted to adjust the length of the pigtail.

6. The OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber according to claim 5, characterized in that: An optical interface is installed at the free end of the pigtail.

7. The OTDR optical module capable of eliminating the blind area of ​​the initial section of the optical fiber according to any one of claims 1 to 6, characterized in that: The upper shell, the frame and the lower shell are all made of metal materials. After being assembled together, the four peripheries of the frame are exposed, and the PCBA board is in contact with the bottom surface of the frame.

8. The OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber according to claim 7, characterized in that: A heat-conducting sealant is filled in the window area of ​​the frame, and the top surface of the heat-conducting sealant is in contact with the upper shell.

9. The OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber according to claim 7, characterized in that: An assembly opening adapted to the outer contour of the electrical connector is provided on the lower shell, and the electrical connector is embedded in the assembly opening; Positioning holes are respectively provided on the electrical connector and the PCBA board, guide pins are installed in the positioning holes, and the installation position of the electrical connector is limited by the guide pins; A metal spring is arranged on the electrical connector, and the metal spring contacts the PCBA board at a fixed point to achieve electrical connection.

10. The OTDR optical module capable of eliminating the blind area of ​​the initial section of an optical fiber according to any one of claims 1 to 6, characterized in that: A support foot is formed on the bottom surface of the lens unit, the lens unit is mounted on the PCBA board through the support foot, and a gap is formed between the bottom surface of the lens unit and the PCBA board; The optical device is located at the gap below the lens unit.

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