Transceiver optical components, optical monitoring modules and optical modules

Abstract

The present invention is applicable to the field of optical communication technology, and provides a transceiver optical component, an optical monitoring module, and an optical module. The transceiver optical component includes a polarization beam splitter and combiner, a non-reciprocal polarization reflector located on the first side of the polarization beam splitter and combiner, a first bandpass polarization reflector located on the second side of the polarization beam splitter and combiner, and a second bandpass polarization reflector located on the third side of the polarization beam splitter and combiner; the second side of the polarization beam splitter and combiner is an adjacent side of the first side of the polarization beam splitter and combiner, and the third side of the polarization beam splitter and combiner is an opposite side of the second side of the polarization beam splitter and combiner; wherein the polarization beam splitter and combiner is used to transmit a first polarization signal and reflect a second polarization signal; the first polarization signal is an optical signal whose polarization state is a first polarization state, and the second polarization signal is an optical signal whose polarization state is a second polarization state. The transceiver optical component, the optical monitoring module, and the optical module provided by the present invention are small in size and low in cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical communication, and in particular relates to a transceiver optical component, an optical monitoring module and an optical module. Background Art

[0002] The operation and maintenance of optical fiber networks cannot be separated from the monitoring of the physical status of optical fiber networks. Optical time-domain reflectometer (OTDR) and optical supervisory channel (OSC) are two of the main monitoring methods. Specifically, OTDR is a technical method that measures the Fresnel back reflection and Rayleigh scattering in optical fibers to obtain the uniformity, defects, fractures, joint coupling and other properties of optical fibers. It can be used to measure optical fiber attenuation, joint loss, locate optical fiber fault points, and understand the loss distribution along the length of optical fibers. The optical supervisory channel refers to the monitoring wavelength (monitoring channel) generated by the node inserted at the transmitting end of the optical fiber signal transmission system, and the monitoring wavelength is separated at the receiving end of the transmission system to test and monitor the optical fiber connection status and performance of the optical fiber transmission system.

[0003] Performing bidirectional optical time domain reflectometry and optical monitoring channels in a single optical fiber is the most concise and effective way to monitor the physical status of the optical fiber network. In addition, network operators hope that the single-fiber bidirectional OTDR+OSC system can be integrated into an SFP (Small Form-factor Pluggable) optical module, which requires an integrated small-volume transceiver optical component.

[0004] However, the current single-fiber bidirectional OTDR+OSC system, such as Figure 1 As shown, there is an OTDR+OSC system A and B at each end of a single-fiber bidirectional transmission optical fiber 101, and each system includes a signal sending laser, LD-A-λ 1 and LD-B-λ 2 , respectively sending wavelength λ 1 and λ 2 The optical signal of the locally transmitted wavelength becomes an OSC signal when it reaches the other party, and becomes an OTDR signal when it is reflected by the single-fiber bidirectional transmission optical fiber 101.

[0005] Therefore, each single-fiber bidirectional OTDR+OSC system must receive signals of two wavelengths, one is the OSC signal sent by the other party, and the other is the OTDR signal formed by the reflection of the local wavelength by the single-fiber bidirectional transmission fiber 101. After the two signals enter the single-fiber bidirectional OTDR+OSC system, a three-port fiber WDM (Wavelength Division Multiplexing) device 102 is used to separate the OTDR / OSC signal, and then another three-port optical circulator 103 is used to separate the transmission signal and the reflection signal of the same wavelength. The separated signals are transmitted by OTDR-A-λ at the A end. 1 Detector (photodetector, PD) and OSC-A-λ 2 The detector receives the signal and is then received by OSC-B-λ at the B end. 1 Detector and OTDR-B-λ 2 Detector receiving.

[0006] It can be seen that the existing solution uses discrete optical fiber devices (optical fiber WDM devices and optical circulators), which are large in size and high in cost, and cannot meet the requirements of integrating transceiver optical components into SFP optical modules. Summary of the invention

[0007] The object of the present invention is to provide a transceiver optical component, an optical monitoring module and an optical module, aiming to solve the technical problem of large volume of the transceiver optical component used for optical signal monitoring in the prior art.

[0008] The present invention is implemented in this way. In a first aspect, a transceiver optical component is provided, comprising a polarization beam splitter and combiner, a non-reciprocal polarization reflector located on a first side of the polarization beam splitter and combiner, a first bandpass polarization reflector located on a second side of the polarization beam splitter and combiner, and a second bandpass polarization reflector located on a third side of the polarization beam splitter and combiner; the second side of the polarization beam splitter and combiner is an adjacent side to the first side of the polarization beam splitter and combiner, and the third side of the polarization beam splitter and combiner is an opposite side to the second side of the polarization beam splitter and combiner;

[0009] The polarization beam splitter / combiner is used to transmit a first polarization signal and reflect a second polarization signal; the first polarization signal is an optical signal with a polarization state of the first polarization state, and the second polarization signal is an optical signal with a polarization state of the second polarization state;

[0010] The non-reciprocal polarization reflector is used to transmit the first optical signal and convert the polarization state of the first optical signal into the first polarization state, and is also used to reflect the OTDR signal and the OSC signal transmitted by the polarization beam splitter and combiner, and convert the polarization state of the OTDR signal and the OSC signal from the first polarization state to the second polarization state; the wavelength of the OSC signal is different from the wavelength of the OTDR signal;

[0011] The first bandpass polarization reflector is used to reflect the OTDR signal reflected by the polarization splitter / combiner, and convert the polarization state of the OTDR signal from the second polarization state to the first polarization state, and transmit all OSC signals conducted by the polarization splitter / combiner;

[0012] The second bandpass polarization reflector is used to reflect the OSC signal reflected by the polarization splitter / combiner, and convert the polarization state of the OSC signal from the second polarization state to the first polarization state, and transmit all OTDR signals conducted by the polarization splitter / combiner.

[0013] In an optional embodiment, the non-reciprocal polarization reflector includes a sub-wavelength grating polarization reflector and a 45-degree Faraday rotator sequentially arranged along a propagation direction of the first optical signal;

[0014] Among them, the sub-wavelength grating polarization reflector is used to transmit light signals with polarization directions the same as its own metal grid line periodic direction, and reflect light signals with polarization directions perpendicular to its own metal grid line periodic direction, and the 45-degree Faraday rotator is used to rotate the polarization direction of the light signal by 45 degrees.

[0015] In an optional embodiment, the sub-wavelength grating polarization reflector is formed on the corresponding light-transmitting surface of the 45-degree Faraday rotator.

[0016] In an optional embodiment, the polarization beam splitter / combiner is a multi-layer dielectric film type polarization beam splitter / combiner.

[0017] In an optional embodiment, the first bandpass polarization reflector includes a polarization rotator disposed near the polarization beam splitter / combiner and a bandpass reflector located on a second side of the polarization rotator;

[0018] The second side of the polarization rotator is a side corresponding to the second side of the polarization beam splitter / combiner, the polarization rotator is used to rotate the polarization direction of the linear polarized light by 90 degrees after passing through twice, and the bandpass reflector is used to reflect the OTDR signal and transmit the OSC signal.

[0019] In an optional embodiment, the polarization rotator is a 1 / 4 wave plate or a 45-degree Faraday rotator.

[0020] In an optional embodiment, the bandpass reflector is realized by coating a multi-layer dielectric film on the light output surface of the polarization rotator.

[0021] In an optional embodiment, the structure of the second bandpass polarization reflector is the same as that of the first bandpass polarization reflector.

[0022] In a second aspect, an optical monitoring module is provided, including a transceiver optical component, an optical signal transmitting unit, an input and output terminal, a first optical signal receiving unit, and a second optical signal receiving unit;

[0023] Among them, the transceiver optical component is the transceiver optical component provided by the first aspect; the optical signal transmitting unit is located on the first side of the non-reciprocal polarization reflector, for transmitting a first optical signal; the first side of the non-reciprocal polarization reflector is the side corresponding to the first side of the polarization beam splitter and combiner; the input and output ends are located on the fourth side of the polarization beam splitter and combiner, for inputting and outputting optical signals; the fourth side of the polarization beam splitter and combiner is the opposite side of the first side of the polarization beam splitter and combiner; the first optical signal receiving unit is located on the third side of the transceiver optical component, for receiving and processing the OTDR signal transmitted by the transceiver optical component; the second optical signal receiving unit is located on the second side of the transceiver optical component, for receiving and processing the OSC signal transmitted by the transceiver optical component; the second side of the transceiver optical component is the side corresponding to the second side of the polarization beam splitter and combiner, and the third side of the transceiver optical component is the side corresponding to the third side of the polarization beam splitter and combiner.

[0024] According to a third aspect, an optical module is provided, comprising a housing and the optical monitoring module provided by the second aspect installed in the housing.

[0025] The technical effect of the first aspect of the present invention relative to the prior art is that the transceiver optical component provided by the embodiment of the present invention can not only realize the separation of OTDR signals and OSC signals in different wavelength ranges, but also realize the separation of the transmission signal (the above-mentioned first optical signal) and the receiving signal (OTDR signal) in the same wavelength range, that is, the combined function of the optical fiber WDM device and the optical circulator in the prior art can be realized, the volume of the transceiver optical component can be effectively reduced, and the cost of the required components is lower than that of the transceiver optical component in the prior art, and can meet the use requirements of integration into the SFP optical module. In addition, by using the transceiver optical component provided by the embodiment of the present invention, even if the wavelengths of the optical signals emitted by the two paired optical monitoring modules are similar, that is, λ 1 and λ 2 The values ​​are similar, and the above functions can be easily realized, and each component is easy to manufacture and has low cost.

[0026] It can be understood that the beneficial effects of the second to third aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0028] Figure 1 It is a schematic diagram of the structure and optical path of the optical signal monitoring system of the prior art;

[0029] Figure 2 It is a schematic diagram of the structure and optical path of an optical monitoring module provided by an embodiment of the present invention;

[0030] Figure 3a is a schematic diagram of the reflection characteristics of the polarization beam splitter and combiner used in one embodiment of the present invention;

[0031] Figure 3b is a schematic diagram of reflection characteristics of a polarization beam splitter and combiner used in another embodiment of the present invention;

[0032] Figure 4 Schematic diagram of the structure and optical path of a non-reciprocal polarization reflector used in one embodiment of the present invention;

[0033] Figure 5 Schematic diagram of the structure and optical path of the first bandpass polarization reflector used in an embodiment of the present invention;

[0034] Figure 6 yes Figure 5 A schematic diagram of reflection characteristics of the first bandpass polarization reflector shown;

[0035] Figure 7 It is a schematic diagram of the reflection characteristics of the second bandpass polarization reflector used in an embodiment of the present invention.

[0036] Description of reference numerals:

[0037] 101. Single-fiber bidirectional transmission optical fiber; 102. Optical fiber WDM device; 103. Optical circulator; 110. Polarization splitter and combiner; 120. Non-reciprocal polarization reflector; 121. Sub-wavelength grating polarization reflector; 122. 45-degree Faraday rotator; 130. First bandpass polarization reflector; 131. Polarization rotator; 132. Bandpass reflector; 140. Second bandpass polarization reflector; 200. Optical signal transmitting unit; 300. Input and output end; 400. First optical signal receiving unit; 500. Second optical signal receiving unit. DETAILED DESCRIPTION

[0038] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0039] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the 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 cannot be understood as a limitation on the present invention.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0041] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0043] In order to solve the problems existing in the prior art, an embodiment of the present invention provides a transceiver optical component, which can realize the functions of the optical fiber WDM device and the optical circulator in the prior art. Applying it to the optical monitoring module can enable the optical monitoring module to integrate OTDR and OSC functions, and has a small size and low cost, so that the optical monitoring module can be packaged into an SFP optical module.

[0044] Specifically, to realize the OTDR and OSC functions, two optical monitoring modules are generally required, and the two are connected through a single-fiber bidirectional transmission optical fiber. One optical monitoring module is used to send a wavelength of λ to the single-fiber bidirectional transmission optical fiber. 1 The other optical monitoring module is used to send an optical signal with a wavelength of λ to the single-fiber bidirectional transmission optical fiber. 2 The optical signal is then sent 1 The optical monitoring module of the optical signal can receive the first OTDR signal formed by the reflection of the single-fiber bidirectional transmission optical fiber and the first OSC signal transmitted by the single-fiber bidirectional transmission optical fiber, and then send λ 2 The optical monitoring module of the optical signal can receive the second OTDR signal formed by the reflection of the single-fiber bidirectional transmission optical fiber and the second OSC signal conducted by the single-fiber bidirectional transmission optical fiber.

[0045] Among them, the first OTDR signal has a wavelength of λ 1 The optical signal is reflected by the single-fiber bidirectional transmission fiber to form an OTDR signal, and the second OTDR signal is a wavelength of λ 2 The OTDR signal formed by the reflection of the optical signal of the single-fiber bidirectional transmission fiber, the first OSC signal is the wavelength of λ 2 The OSC signal is formed after the optical signal is transmitted through the single-fiber bidirectional transmission optical fiber, and the second OSC signal is a wavelength of λ 1 The OSC signal is formed after the optical signal is transmitted through a single-fiber bidirectional transmission optical fiber.

[0046] It should be noted that the above optical signals generally have a certain wavelength range, that is, the above λ 1 and λ 2 Each is a range value.

[0047] For details, please refer to Figure 2 As shown, the optical monitoring module includes a transceiver optical component, an optical signal transmitting unit 200, an input / output terminal 300, a first optical signal receiving unit 400, and a second optical signal receiving unit 500. The optical signal transmitting unit 200 is used to transmit a first optical signal. The input / output terminal 300 is used to input and output optical signals. The first optical signal receiving unit 400 is used to receive and process an OTDR signal transmitted by the transceiver optical component. The second optical signal receiving unit 500 is used to receive and process an OSC signal transmitted by the transceiver optical component. The transceiver optical component adopts the transceiver optical component provided by an embodiment of the present invention.

[0048] The transceiver optical assembly provided by the embodiment of the present invention includes a polarization beam splitter / combiner 110, a non-reciprocal polarization reflector 120 located on a first side of the polarization beam splitter / combiner 110, a first bandpass polarization reflector 130 located on a second side of the polarization beam splitter / combiner 110, and a second bandpass polarization reflector 140 located on a third side of the polarization beam splitter / combiner 110. Specifically, the polarization beam splitter / combiner 110 generally has a plurality of side surfaces, that is, has multiple sides, the second side of the polarization beam splitter / combiner 110 is an adjacent side to the first side of the polarization beam splitter / combiner 110, and the third side of the polarization beam splitter / combiner 110 is an opposite side to the second side of the polarization beam splitter / combiner 110.

[0049] The polarization beam splitter / combiner 110 is used to transmit the first polarization signal and reflect the second polarization signal. The first polarization signal is an optical signal with a polarization state of the first polarization state, and the second polarization signal is an optical signal with a polarization state of the second polarization state. The optical signal mentioned here includes the first optical signal, OTDR signal and OSC signal mentioned below.

[0050] It should be noted that the first polarization state and the second polarization state in this article are generally two polarization states with polarization directions perpendicular to each other, such as light corresponding to one polarization state is P polarized light, and light corresponding to the other polarization state is S polarized light. For ease of description, the following description is based on the example that the light corresponding to the first polarization state is P polarized light and the light corresponding to the second polarization state is S polarized light. It should be understood that when the light corresponding to the first polarization state is S polarized light and the light corresponding to the second polarization state is P polarized light, the principle is the same as when the light corresponding to the first polarization state is P polarized light and the light corresponding to the second polarization state is S polarized light, except that the polarization directions of the corresponding optical signals are different.

[0051] The non-reciprocal polarization reflector 120 is used to transmit the first optical signal and convert the polarization state of the first optical signal into the first polarization state, and is also used to reflect the OTDR signal and the OSC signal transmitted by the polarization splitter and combiner 100, and convert the polarization state of the OTDR signal and the OSC signal from the first polarization state to the second polarization state. Specifically, the OTDR signal is the optical signal that is reflected back from the single-fiber bidirectional transmission optical fiber 101 after the first optical signal (i.e., the first optical signal with the first polarization state) transmitted through the polarization splitter and combiner has the first polarization state and the second polarization state, and the optical signal with the first polarization state in the OTDR signal is transmitted through the polarization splitter and combiner. The OSC signal is an optical signal sent by another optical monitoring module transmitted through the single-fiber bidirectional transmission optical fiber 101, and has the first polarization state and the second polarization state, and the optical signal with the first polarization state in the OSC signal is transmitted through the polarization splitter and combiner. The wavelength of the OSC signal is different from that of the OTDR signal.

[0052] It should be noted that the first optical signal, OTDR signal and OSC signal in this embodiment are all optical signals with a certain wavelength range. The wavelength of the OSC signal is different from that of the OTDR signal, which means that there is no overlapping area between their wavelength ranges.

[0053] The first bandpass polarization reflector 130 is used to reflect the OTDR signal reflected by the polarization splitter / combiner 110 (i.e., the optical signal whose polarization state is the second polarization state in the OTDR signal), and convert the polarization state of the OTDR signal from the second polarization state to the first polarization state, and transmit the OSC signal conducted by the polarization splitter / combiner 110. The OSC signal mentioned here includes both the OSC signal whose polarization state is the first polarization state and the OSC signal whose polarization state is the second polarization state.

[0054] The second bandpass polarization reflector 140 is used to reflect the OSC signal reflected by the polarization splitter / combiner 110 (i.e., the optical signal whose polarization state is the second polarization state in the OSC signal), and convert the polarization state of the OSC signal from the second polarization state to the first polarization state, and transmit the OTDR signal conducted by the polarization splitter / combiner 110. The OTDR signal mentioned here includes both the OTDR signal whose polarization state is the first polarization state and the OTDR signal whose polarization state is the second polarization state.

[0055] The working principle of the optical monitoring module using the transceiver optical component provided by the embodiment of the present invention is as follows. For the convenience of description and understanding, the OTDR and OSC functions are described separately.

[0056] OTDR functions:

[0057] The optical signal transmitting unit 200 transmits a first optical signal, the wavelength passband of which is λ 1 , contains only a single polarization component, denoted as λ 1O After that, the first optical signal λ 1O The polarization signal (denoted as λ) is transmitted through the non-reciprocal polarization reflector 120 to form a polarization state of the first polarization state. 1p ), then the polarization signal λ 1p After being transmitted through the polarization splitter and combiner 110, it propagates to the single-fiber bidirectional transmission optical fiber 101 through the input and output end 300, and finally reflects from the single-fiber bidirectional transmission optical fiber 101 to form an OTDR signal. At this time, due to the deflection effect of the optical fiber, the OTDR signal reflected from the single-fiber bidirectional transmission optical fiber 101 has two mutually perpendicular polarization components, denoted as λ 1s ' and λ 1p '. Then the polarization state of the optical signal λ in the OTDR signal is the first polarization state 1p 'Can be along the above polarization signal λ 1pThe propagation path is returned, and is propagated to the non-reciprocal polarization reflector 120 through the input and output end 300 and the polarization splitter and combiner 110 in sequence, and then reflected by the non-reciprocal polarization reflector 120 to form an OTDR signal λ with a polarization state of the second polarization state. 1s ', then the signal λ 1s 'Then it is reflected by the polarization splitter and combiner 110 in sequence, transmitted by the second bandpass polarization reflector 140, and finally received by the first optical signal receiving unit 400.

[0058] At the same time, the polarization state of the OTDR signal fed back by the transmission fiber is the optical signal of the second polarization state, that is, λ 1s ', it first passes through the input and output end 300 into the optical monitoring module, then is reflected by the polarization splitter and combiner 110 to the first bandpass polarization reflector 130, and then is reflected by the first bandpass polarization reflector 130 to change the polarization state from the second polarization state to the first polarization state, that is, to become the optical signal λ 1p ', and then the signal is transmitted through the polarization splitter and combiner 110 and the second bandpass polarization reflector 140 in sequence, and is finally received by the first optical signal receiving unit 400.

[0059] After receiving the above two OTDR signals, the first optical signal receiving unit 400 processes them to generate corresponding electrical signals and analyzes them to obtain corresponding detection parameters, or generates corresponding electrical signals and sends them to an external signal processing device, which processes them to obtain corresponding detection parameters.

[0060] OSC Function:

[0061] The second optical signal (wavelength passband is λ) sent by another optical monitoring module 2 ), after being transmitted through the single-fiber bidirectional transmission optical fiber 101, a corresponding OSC signal is generated. The OSC signal also contains two polarization components, S and P, which are denoted as λ 2s and λ 2p Then the polarization state of the optical signal λ in the OSC signal is the first polarization state 2p It can be transmitted to the non-reciprocal polarization reflector 120 through the input and output end 300 and the polarization splitter and combiner 110 in sequence, and then reflected by the non-reciprocal polarization reflector 120 to form an OSC signal λ with a polarization state of the second polarization state. 2s , after which the signal λ 2s Then, it is reflected by the polarization splitter / combiner 110 and the second bandpass polarization reflector 140 in sequence, and the polarization state is changed from the second polarization state to the first polarization state again, that is, the optical signal λ 2p , and then the signal is transmitted through the polarization splitter / combiner 110 and the first bandpass polarization reflector 130 in sequence, and is finally received by the second optical signal receiving unit 500 .

[0062] At the same time, the polarization state of the OSC signal fed back by the transmission fiber is the optical signal of the second polarization state, i.e., λ 2s , it first enters the optical monitoring module through the input and output end 300, then is reflected by the polarization splitter and combiner 110 in sequence, is transmitted through the first bandpass polarization reflector 130, and is finally received by the second optical signal receiving unit 500.

[0063] It should be noted that Figure 2 The separation of the two optical paths with parallel propagation directions is only for the convenience of drawing illustrations. The actual positions may be the same or have a certain spacing, which may be determined according to the actual optical paths.

[0064] It can be seen that the transceiver optical component provided by the embodiment of the present invention can not only realize the separation of OTDR signals and OSC signals in different wavelength ranges, but also realize the separation of the transmission signal (the above-mentioned first optical signal) and the receiving signal (OTDR signal) in the same wavelength range, that is, the combined function of the optical fiber WDM device and the optical circulator in the prior art can be realized, and the volume of the transceiver optical component can be effectively reduced. The cost of the required components is lower than that of the transceiver optical component in the prior art, and can meet the requirements for integration into the SFP optical module. In addition, by using the transceiver optical component provided by the embodiment of the present invention, even if the wavelengths of the optical signals emitted by the two paired optical monitoring modules are similar, that is, λ 1 and λ 2 The values ​​are similar, and the above functions can be easily realized, and each component is easy to manufacture and has low cost.

[0065] The non-reciprocal polarization reflector 120 may be arranged in a variety of ways. For ease of understanding, examples are given below.

[0066] In an optional embodiment, if Figure 4 As shown, the non-reciprocal polarization reflector 120 includes a sub-wavelength grating polarization reflector 121 and a 45-degree Faraday rotator 122 which are sequentially arranged along the propagation direction of the first optical signal.

[0067] Among them, the sub-wavelength grating polarization reflector 121 is used to transmit light signals with the same polarization direction as its own metal grid line periodic direction, and reflect light signals with polarization directions perpendicular to its own metal grid line periodic direction, and the 45-degree Faraday rotator 122 is used to rotate the polarization direction of the light signal by 45 degrees.

[0068] Specifically, the sub-wavelength grating polarized reflector 121 has broadband polarized reflection performance, generally has a plurality of metal grid lines arranged periodically along a certain direction, can transmit polarized light whose polarization direction is consistent with the periodic direction of the metal grid lines, and reflect polarized light whose polarization direction is perpendicular to the periodic direction of the metal grid lines. The periodic direction of the metal grid lines mentioned here refers to the arrangement direction of the metal grid lines, which is generally perpendicular to the extension direction of the metal grid lines. Figure 4 In the configuration shown, the initial polarization direction of the first optical signal emitted by the optical signal transmitting unit 200 is consistent with the periodic direction of the metal grid lines, and at this time, the polarization direction of the first optical signal and the periodic direction of the metal grid lines both form an angle of 45 degrees with the polarization direction corresponding to the first polarization state.

[0069] When in use, the first optical signal first passes through the sub-wavelength grating polarization reflector 121, at which time the polarization direction of the first optical signal remains unchanged, and then the first optical signal is rotated 45 degrees by the 45-degree Faraday rotator 122, and the polarization direction is adjusted to the first polarization state. At this time, the OTDR signal with the first polarization state is recorded as λ 1p '.

[0070] When the OTDR signal with the first polarization state propagates from the side where the polarization beam splitter and combiner 110 is located to the non-reciprocal polarization reflector 120, it will first pass through the 45-degree Faraday rotator 122 and be rotated 45 degrees, so that the polarization direction is perpendicular to the periodic direction of the metal grid lines in the sub-wavelength grating polarization reflector 121, so it will be reflected by the metal grid lines and propagate again in the direction where the 45-degree Faraday rotator 122 is located, and then rotated 45 degrees by the 45-degree Faraday rotator 122 again to adjust to the second polarization state. At this time, the OTDR signal with the second polarization state is recorded as λ 1s '.

[0071] It should be noted that Figure 4 Medium 1p ' and λ 1s The separation of ' is only for the convenience of drawing, the actual positions are the same.

[0072] The non-reciprocal polarization reflector 120 adopts the structure provided by this embodiment, which has a simple structure, is easy to obtain materials and assemble, and has a low cost.

[0073] The above-mentioned sub-wavelength grating polarization reflector 121 can be one of the three types of gratings, namely, sub-wavelength medium, sub-wavelength metal, and sub-wavelength medium and metal mixture, or can be formed by directly forming one of the above three types of gratings on a light-transmitting surface of the 45-degree Faraday rotator 122 through a micro-machining process. When the sub-wavelength grating polarization reflector 121 is provided independently of the 45-degree Faraday rotator 122, it is convenient to obtain materials and assemble. When the sub-wavelength grating polarization reflector 121 is directly formed on the corresponding light-transmitting surface of the 45-degree Faraday rotator 122 through a micro-machining process, the volume of the non-reciprocal polarization reflector 120 can be made smaller.

[0074] Of course, in other embodiments, the non-reciprocal polarization reflector can also adopt other structures, such as adding a half-wave plate to adjust the polarization direction, so that the geometric configuration of the polarization beam splitter 123 is consistent with the polarization beam splitter and combiner 110 for easy assembly, as well as other variations, as long as the above functions can be achieved.

[0075] In an optional embodiment, if Figure 2 As shown, the polarization beam splitter and combiner 110 is a multi-layer dielectric film type polarization beam splitter and combiner. Specifically, the polarization beam splitter and combiner 110 has a filter layer formed by multiple dielectric films, which can transmit the optical signal with the first polarization state and reflect the optical signal with the second polarization state, that is, only allow the above-mentioned λ 1p , 1p ' and λ 2p Transmission, and λ 1s , 1s ' and λ 2s The reflection characteristics are as follows Figure 3a as shown; or Figure 3b As shown, the filter layer can transmit the optical signal with the second polarization state and reflect the optical signal with the first polarization state.

[0076] Figure 3a and Figure 3b The dashed line is the reflection spectrum of S light, and the solid line is the reflection spectrum of P light. Figure 3a It can be seen that the reflection spectrum of P light is 1 Passband and λ 2 The reflectivity in the passband is close to zero, which means it can be transmitted; the reflectivity of the S light in the λ1 and λ2 passbands is close to 100%. Figure 3b It can be seen that the reflection spectrum of P light is 1 Passband and λ 2 The reflectivity in the passband is close to 100%; the reflectivity of the S light in the λ1 and λ2 passbands is close to zero, so it can be transmitted.

[0077] In addition, the use conditions of the polarization beam splitter and combiner 110 are generally large-angle incidence and reflection, that is, the above-mentioned filter layer is generally set at an angle, and the inclination angle is generally 45 degrees. Of course, other angles can also be used, such as 30 degrees, 60 degrees, etc., as long as it can meet its use requirements.

[0078] The polarization beam splitter and combiner 110 adopts the structure provided in this embodiment, which has a simple structure and is easy to prepare.

[0079] In addition to the above-mentioned filter layer, the polarization beam splitter and combiner 110 may also include other light guides, such as two triangular prisms that can be spliced ​​into a quadrangular prism, in which case the filter layer can be formed between the two triangular prisms. In this way, it is helpful to shape the filter layer and protect the filter layer. Of course, in other embodiments, only one prism can be provided, and the filter layer can be plated on one of the light-transmitting surfaces of the prism. This is not a sole limitation, as long as the above-mentioned functions can be achieved.

[0080] In an optional embodiment, if Figure 5 As shown, the first bandpass polarization reflector 130 includes a polarization rotator 131 disposed near the polarization beam splitter / combiner 110 and a bandpass reflector 132 located on the second side of the polarization rotator 131. The second side of the polarization rotator 131 is a side corresponding to the second side of the polarization beam splitter / combiner 110, and is also a side of the polarization rotator 131 away from the polarization beam splitter / combiner 110, that is, the bandpass reflector 132 is disposed away from the polarization beam splitter / combiner 110. The polarization rotator 131 is used to rotate the polarization direction of the linear polarized light by 90 degrees after passing through twice, and the bandpass reflector 132 is used to reflect the OTDR signal and transmit the OSC signal.

[0081] Specifically, the first bandpass polarization reflector 130 is used under the condition of small angle incidence, transmission or reflection, about 0 degree incidence, and of course other angles of incidence can also be used as long as the above functions can be achieved. Figure 6 As shown in the reflection characteristics, since the first bandpass polarization reflector 130 is used under the condition of small angle incidence, the S light and the P light have approximately the same reflection spectrum. 1 The passband is totally reversed, for λ 2 The passband is fully transparent. 2 The passband light will pass through the first bandpass polarization reflector 130 and become a λ 2 Passband light.

[0082] When in use, the OTDR signal with the second polarization state is reflected by the polarization splitter / combiner 110 and propagates to the polarization rotator 131. After transmission, it is reflected by the bandpass reflector 132 and passes through the polarization rotator 131 again. The polarization direction of the OTDR signal is rotated 90 degrees after passing through the polarization rotator 131 twice, and its polarization state is converted from the second polarization state to the first polarization state. Then, the OTDR signal passes through the polarization splitter / combiner and is received by the first optical signal receiving unit.

[0083] At the same time, the OSC signal can be reflected by the polarization splitter and combiner and propagate to the first bandpass polarization reflector 130, and then can pass through the polarization rotator 131 and the bandpass reflector 132 in sequence to be received by the second optical signal receiving unit.

[0084] The first bandpass polarization reflector 130 adopts the structure provided by this embodiment, which has a simple structure and is easy to assemble.

[0085] The polarization rotator can be a quarter wave plate, a 45-degree Faraday rotator, or other structures that can achieve the above functions. When the polarization rotator is a quarter wave plate, it is cheap and small. When the polarization rotator is a 45-degree Faraday rotator, it is not necessary to consider the direction of the optical axis, which is convenient for assembly.

[0086] The bandpass reflector can be a separate bandpass reflector or can be realized by coating a multilayer dielectric film on the light-emitting surface of the polarization rotator. When the bandpass reflector is made by coating, the volume of the first bandpass polarization reflector is smaller.

[0087] In an optional embodiment, the structure of the second bandpass polarization reflector is the same as that of the first bandpass polarization reflector, but the functions of the two are slightly different. The second bandpass polarization reflector is used for transmitting OTDR signals and reflecting OSC signals. Its reflection characteristics are as follows: Figure 7 As shown, the first bandpass polarization reflector is used for transmitting the OSC signal and reflecting the OTDR signal. Its reflection characteristics are as follows: Figure 6 By adopting the above structure, the structure of the second bandpass polarization reflector can be made simple and easy to assemble.

[0088] Please refer to Figure 2 As shown, in another embodiment of the present invention, an optical monitoring module is provided, including a transceiver optical component, an optical signal transmitting unit 200 , an input and output terminal 300 , a first optical signal receiving unit 400 and a second optical signal receiving unit 500 .

[0089] Among them, the transceiver optical component is the transceiver optical component provided by the above-mentioned embodiments. The optical signal transmitting unit 200 is located on the first side of the non-reciprocal polarization reflector 120, and is used to emit a first optical signal. The first side of the non-reciprocal polarization reflector 120 is the side corresponding to the first side of the polarization beam splitter / combiner 110, and is also the side away from the polarization beam splitter / combiner 110. The input and output end 300 is located on the fourth side of the polarization beam splitter / combiner 110, and is used to input and output optical signals. The fourth side of the polarization beam splitter / combiner 110 is the opposite side of the first side of the polarization beam splitter / combiner 110. The first optical signal receiving unit 400 is located on the third side of the transceiver optical component, and is used to receive and process the OTDR signal transmitted by the transceiver optical component. The second optical signal receiving unit 500 is located on the second side of the transceiver optical component, and is used to receive and process the OSC signal transmitted by the transceiver optical component. The second side of the transceiver optical component is a side corresponding to the second side of the polarization beam splitter / combiner 110 , and the third side of the transceiver optical component is a side corresponding to the third side of the polarization beam splitter / combiner 110 .

[0090] Specifically, the optical signal transmitting unit 200 in this embodiment can be one or more laser transmitters. The input and output ends 300 are generally optical fibers, which are used to transmit the optical signal output by the optical monitoring module to the transmission optical fiber, and are also used to receive the OSC signal transmitted by the transmission optical fiber and the OTDR signal reflected back. The structures of the first optical signal receiving unit 400 and the second optical signal receiving unit 500 can be the same or different, and can include detectors respectively, or can include detectors and a signal processing device electrically connected to the detector. The specific selection can be flexibly based on the use needs, and no unique limitation is made here.

[0091] The working principle of the optical monitoring module provided by the embodiment of the present invention is as follows:

[0092] Transmit: The λ emitted by the optical signal transmitting unit 200 1O After passing through the non-reciprocal polarization reflector 120, the polarization state rotates 45 degrees to become λ 1p , further transmitted through the polarization beam splitter and combiner 110, reaches the input-output end 300, and then output to the external transmission optical fiber through the input-output end 300.

[0093] Receive OTDR signal: λ 1 ' is the wavelength of the OTDR signal reflected from the transmission fiber, which is the same as the wavelength of λ1O, including λ 1p ' and λ 1s The two components of ' are input to the polarization beam splitter and combiner 110 through the input and output end 300, according to Figure 4 The reflection spectrum shown, λ 1s ' is reflected, λ 1p 'Being transmitted;

[0094] λ 1s After reaching the first bandpass polarization reflector 130 and being reflected, the polarization state rotates 90 degrees to become λ 1p ' Returns and passes through the polarization splitter and combiner 110 and the second bandpass polarization reflector 140 in sequence, reaches the first optical signal receiving unit 400 and is received by it.

[0095] λ 1p After passing through the polarization beam splitter and combiner 110, it reaches the non-reciprocal polarization reflector 120 and is reflected while the polarization state is rotated 90 degrees to become λ 1s ' Returns and is reflected by the polarization splitter and combiner 110, and is transmitted by the second bandpass polarization reflector 140, and reaches the first optical signal receiving unit 400 and is received by it.

[0096] It can be seen that the first optical signal receiving unit 400 receives the two polarization state signals of the OTDR and is complete.

[0097] Receive OSC signal: λ 2is the far-end emission wavelength transmitted by the transmission fiber, including λ 2p and λ 2s The two components of are input into the polarization beam splitter and combiner 110 through the input and output end 300. Figure 3a and Figure 3b The reflection spectrum shown, λ 2s When passing through the polarization beam splitter and combiner 110, it will be reflected and reach the first bandpass polarization reflector 130 according to Figure 6 The characteristics shown in FIG. 5 can be transmitted through and finally reach the second optical signal receiving unit 500 and be received by it; λ 2p When passing through the polarization beam splitter and combiner 110, it is transmitted and then reflected by the non-reciprocal polarization reflector 120, and the polarization state is rotated by 90 degrees to become λ 2s Returning and sequentially reflected by the polarization beam splitter and combiner 110 and the second bandpass polarization reflector 140, it becomes λ again 2p , and then sequentially transmits through the polarization beam splitter / combiner 110 and the first bandpass polarization reflector 130, and finally reaches and is received by the second optical signal receiving unit 500. The second optical signal receiving unit 500 receives the two polarization state signals of the OSC, which are also complete.

[0098] The optical monitoring module provided in the embodiment of the present invention adopts the transceiver optical components provided in the above embodiments, and integrates the OTDR function and the OSC function into one, so that the module itself is small in size and low in cost, and is easy to assemble into the SFP optical module. Even if the wavelengths of the optical signals emitted by the two paired optical monitoring modules are similar, that is, λ 1 and λ 2 The values ​​are similar, and the above functions can be easily realized. At the same time, each component is easy to manufacture and has low cost.

[0099] In another embodiment of the present invention, an optical module is provided, including a housing and the optical monitoring module provided by the above embodiment installed in the housing.

[0100] The optical module in this embodiment can be an SFP optical module or other optical modules that can be installed with the above optical monitoring module. The optical module provided in this embodiment adopts the optical monitoring module provided in the above embodiment, which can realize the OTDR+OSC function, and is conducive to its own miniaturization and low-cost design. Even if the wavelengths of the optical signals emitted by the two paired optical monitoring modules are similar, that is, λ 1 and λ 2 The values ​​are similar, and the above functions can be easily realized. At the same time, each component is easy to manufacture and has low cost.

[0101] The above description is only a preferred embodiment of the present invention, and only specifically describes the technical principle of the present invention. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanation here, any modification, equivalent substitution and improvement made within the spirit and principle of the present invention, and other specific embodiments of the present invention that can be associated with by technicians in this field without creative labor, should be included in the scope of protection of the present invention.

Claims

1. A transceiver optical component, characterized in that: The invention comprises a polarization beam splitter and a beam combiner, a non-reciprocal polarization reflector located on a first side of the polarization beam splitter and a beam combiner, a first bandpass polarization reflector located on a second side of the polarization beam splitter and a beam combiner, and a second bandpass polarization reflector located on a third side of the polarization beam splitter and a beam combiner; the second side of the polarization beam splitter and a beam combiner is adjacent to the first side of the polarization beam splitter and a beam combiner, and the third side of the polarization beam splitter and a beam combiner is opposite to the second side of the polarization beam splitter and a beam combiner; The polarization beam splitter / combiner is used to transmit a first polarization signal and reflect a second polarization signal; the first polarization signal is an optical signal with a polarization state of the first polarization state, and the second polarization signal is an optical signal with a polarization state of the second polarization state; The non-reciprocal polarization reflector is used to transmit the first optical signal and convert the polarization state of the first optical signal into the first polarization state, and is also used to reflect the OTDR signal and the OSC signal transmitted by the polarization beam splitter and combiner, and convert the polarization state of the OTDR signal and the OSC signal from the first polarization state to the second polarization state; the wavelength of the OSC signal is different from the wavelength of the OTDR signal; the wavelength of the OSC signal is different from the wavelength of the OTDR signal means that there is no overlapping area between the wavelength ranges of the two; The first bandpass polarization reflector is used to reflect the OTDR signal reflected by the polarization splitter / combiner, and convert the polarization state of the OTDR signal from the second polarization state to the first polarization state, and transmit all OSC signals conducted by the polarization splitter / combiner; The second bandpass polarization reflector is used to reflect the OSC signal reflected by the polarization splitter / combiner, and convert the polarization state of the OSC signal from the second polarization state to the first polarization state, and transmit all OTDR signals conducted by the polarization splitter / combiner.

2. The transceiver optical component according to claim 1, wherein: The non-reciprocal polarization reflector comprises a sub-wavelength grating polarization reflector and a 45-degree Faraday rotator sequentially arranged along the propagation direction of the first optical signal; Among them, the sub-wavelength grating polarization reflector is used to transmit light signals with polarization directions the same as its own metal grid line periodic direction, and reflect light signals with polarization directions perpendicular to its own metal grid line periodic direction, and the 45-degree Faraday rotator is used to rotate the polarization direction of the light signal by 45 degrees.

3. The transceiver optical component according to claim 2, characterized in that: The sub-wavelength grating polarization reflector is formed on the corresponding light passing surface of the 45-degree Faraday rotator.

4. The transceiver optical assembly according to claim 1, wherein: The polarization beam splitter and combiner is a multi-layer dielectric film type polarization beam splitter and combiner.

5. The transceiver optical assembly according to claim 1, wherein: The first bandpass polarization reflector includes a polarization rotator disposed near the polarization beam splitter / combiner and a bandpass reflector located on a second side of the polarization rotator; The second side of the polarization rotator is a side corresponding to the second side of the polarization beam splitter / combiner, the polarization rotator is used to rotate the polarization direction of the linear polarized light by 90 degrees after passing through twice, and the bandpass reflector is used to reflect the OTDR signal and transmit the OSC signal.

6. The transceiver optical component according to claim 5, characterized in that: The polarization rotator is a 1 / 4 wave plate or a 45 degree Faraday rotator.

7. The transceiver optical assembly according to claim 5, wherein: The bandpass reflector is realized by coating a multi-layer dielectric film on the light-emitting surface of the polarization rotator.

8. The transceiver optical component according to any one of claims 5 to 7, characterized in that: The structure of the second bandpass polarization reflector is the same as that of the first bandpass polarization reflector.

9. An optical monitoring module, characterized in that: It includes a transceiver optical component, an optical signal transmitting unit, an input and output end, a first optical signal receiving unit and a second optical signal receiving unit; Wherein, the transceiver optical component is the transceiver optical component described in any one of claims 1 to 8; the optical signal transmitting unit is located on the first side of the non-reciprocal polarization reflector, for transmitting a first optical signal; the first side of the non-reciprocal polarization reflector is the side corresponding to the first side of the polarization beam splitter / combiner; the input and output ends are located on the fourth side of the polarization beam splitter / combiner, for inputting and outputting optical signals; the fourth side of the polarization beam splitter / combiner is the opposite side of the first side of the polarization beam splitter / combiner; the first optical signal receiving unit is located on the third side of the transceiver optical component, for receiving and processing the OTDR signal transmitted by the transceiver optical component; the second optical signal receiving unit is located on the second side of the transceiver optical component, for receiving and processing the OSC signal transmitted by the transceiver optical component; the second side of the transceiver optical component is the side corresponding to the second side of the polarization beam splitter / combiner, and the third side of the transceiver optical component is the side corresponding to the third side of the polarization beam splitter / combiner.

10. An optical module, characterized in that: The optical monitoring module comprises a housing and the optical monitoring module according to claim 9 installed in the housing.

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