Circulator and optical device

Abstract

The invention relates to the technical field of optical devices, and particularly provides a circulator and an optical device, the circulator comprises a front end and a rear end, a transmitting light beam is input from the front end and output from the rear end, a receiving light beam is input from the rear end and output from the front end, and the light beams passing through the front end and the rear end are parallel to each other. The device further comprises a reflector plate, a half slide, a magnetic Faraday optical rotation plate and a plurality of PBS plates. The positions of the three PBS sheets and the three half-glass sheets are reasonably arranged, so that receiving light beams and emitting light beams of the circulator are input and output in parallel from the front end and the rear end, a vertical end is not generated, the metal airtight tubes arranged at the ports of the circulator can be arranged in parallel, and compared with an existing structure of mutually vertical metal airtight tubes, the occupied space is smaller; the structure is more reasonable, the arrangement requirement in a communication module is better met, the arrangement problem of the transceiver in an optical communication module is solved, and the multi-channel transceiver has great advantages especially for the layout of a multi-channel transceiver integrated device.

Description

Technical Field

[0001] The present invention relates to the technical field of optical devices, and specifically provides a circulator and an optical device. Background Art

[0002] Transceivers (hereinafter referred to as transceivers) are often used in optical fiber communication systems. Transceivers can integrate the transmitting and receiving units in one device, which reduces the size and saves optical fiber resources. When the transceiver needs to send and receive signals on the same wavelength, a circulator is usually used. A circulator is a non-reciprocal optical device that allows optical signals to be transmitted in a specific direction while blocking or guiding optical signals in other directions.

[0003] Conventional circulators are generally Figure 1 As shown in the figure, the ports of the transmitting and receiving units are in the vertical direction of the circulator, which will result in the two metal airtight tubes being perpendicular to each other after the metal airtight tubes are installed on the ports of the circulator, and the overall volume of the transceiver is large, which increases the difficulty of subsequent installation in the communication module. Therefore, there is an urgent need for a circulator with a smaller volume that better meets the arrangement requirements in the communication module. Summary of the invention

[0004] To solve the above problems, the present invention provides a circulator and an optical device, which adjust the light beam transmission in the circulator so that the receiving light beam and the transmitting light beam of the transceiver are parallel, so that the transceiver can be arranged more reasonably in the communication module.

[0005] The technical solution of the present invention is as follows:

[0006] A circulator comprises a front end and a rear end, wherein a transmitting light beam is input from the front end and output from the rear end, a receiving light beam is input from the rear end and output from the front end, the light beams passing through the front end and the rear end are parallel to each other, and further comprises a reflector, a half glass plate, a Faraday rotator and a plurality of PBS plates.

[0007] In this scheme, the PBS sheet can polarize and separate ordinary optical signals into a P polarization state light beam and an S polarization state light beam whose polarization states are perpendicular to each other, and the PBS sheet can allow the P polarization state light beam to pass through and reflect the S polarization state light beam. At the same time, the Faraday rotator needs to be magnetic and can change the polarization state angle of the light beam like the half glass sheet. These principles are used to reasonably arrange the positions of the PBS sheet and the half glass sheet, so that the receiving light beam and the transmitting light beam of the circulator are input and output in parallel from the front and rear ends, without generating vertical ports, so that the metal airtight tubes installed at the ports of the circulator can be arranged in parallel next to each other. Compared with the existing structure of mutually perpendicular metal airtight tubes, it occupies less space, has a more reasonable structure, and is more in line with the arrangement requirements in the communication module.

[0008] Preferably, the PBS sheet and the reflector sheet are parallel to each other, the PBS sheet includes a first PBS sheet, a second PBS sheet and a third PBS sheet, the first PBS sheet and the third PBS sheet are located in the front end, the second PBS sheet and the reflector sheet are located in the rear end, the half glass sheet and the Faraday rotator sheet are arranged between the front end and the rear end, the PBS sheet and the reflector sheet together constitute a beam adjustment area, and the emitted light beam and the incident light beam are respectively reflected an even number of times in the beam adjustment area.

[0009] In this solution, the PBS sheet and the reflector sheet are parallel to each other, so that the reflection of the receiving light beam and the transmitting light beam in the beam adjustment area is accurately controllable, ensuring that the initial incident light and the final outgoing light of the light beam are parallel after an even number of reflections.

[0010] Preferably, the half glass plate and the Faraday rotator plate are parallel to each other.

[0011] Preferably, the polarization angle between the optical axis of the half-glass and the P-polarization light beam is 22.5°.

[0012] Preferably, the rotation angle of the Faraday rotator is 45°.

[0013] In this scheme, by limiting the polarization angle of the optical axis of the half-glass, when the light beam passes through the half-glass, it is deflected 45° in different directions according to the different initial polarization states of the light beam and the different incident directions. In conjunction with the parallel Faraday rotator, the polarization angle of the light beam is fixed and deflected 45° in one direction, so that the P-polarization state light beam and the S-polarization state light beam passing through the half-glass and the Faraday rotator can switch with each other or remain unchanged.

[0014] After the above arrangement, preferably, the emission light beam is a P-polarized light beam. In this solution, the emission light beam can be limited to a P-polarized light beam in advance by setting a half glass sheet before the emission light beam enters the light beam adjustment area. Since the P-polarized light beam can directly pass through the PBS sheet, the number of reflections of the emission light beam in the light beam adjustment area can be reduced, and the output position of the emission light beam can be better controlled.

[0015] Preferably, the emission light beam input from the front end passes through the first PBS sheet, passes through the Faraday rotator sheet and the half-glass sheet in sequence, is reflected in the light beam adjustment area and changes the polarization state angle, and then is emitted from the rear end through the second PBS sheet; the receiving light beam input from the rear end passes through the second PBS sheet, passes through the half-glass sheet and the Faraday rotator sheet in sequence, is reflected in the light beam adjustment area and changes the polarization state angle, and then is emitted from the front end through the third PBS sheet.

[0016] In this scheme, since the emission light beam is a P polarized light beam, when it passes through the Faraday rotator and the half glass plate in sequence, the magnitude of the deflection normal angle of the emission light beam is the same and the direction is opposite, and the emission light beam can pass through the first PBS plate, the Faraday rotator, the half glass plate and the second PBS plate in sequence along a straight line, and the incident light and the outgoing light are parallel to each other and have almost no deviation; and the receiving light beam undergoes polarization separation after passing through the second PBS plate, and the P polarized light beam passes through the second PBS plate, and when it passes through the Faraday rotator and the half glass plate in sequence, the magnitude of the deflection normal angle of the emission light beam is the same and the direction is the same, and the P polarized light beam is deflected into an S polarized light beam, and is reflected on the first PBS plate and the third PBS plate in sequence; the S polarized light beam is reflected by the second PBS plate and the reflector, and when it passes through the Faraday rotator and the half glass plate in sequence, the magnitude of the deflection normal angle of the emission light beam is the same and the direction is the same, and the S polarized light beam is deflected into a P polarized light beam, and is directly passed through the third PBS plate, and finally the S polarized light beam and the P polarized light beam separated by the receiving light beam are output together from the front end.

[0017] Preferably, an optical device, any of the above-mentioned circulators, wherein a collimator is arranged at the rear end of the circulator, and the collimator is used to input a receiving light beam and output a transmitting light beam, and two groups of metal airtight tubes are arranged in parallel at the rear end of the circulator, which are respectively used to input a transmitting light beam and output a receiving light beam.

[0018] In this solution, the collimator and the metal airtight tube are respectively arranged in parallel at the rear end and the front end. No port is arranged in the vertical direction of the collimator, so that the metal airtight tube installed at the front end port of the circulator can be arranged in parallel next to each other. Compared with the existing structure of mutually perpendicular metal airtight tubes, it occupies less space, has a more reasonable structure, and is more in line with the arrangement requirements in the communication module.

[0019] Beneficial effects of the present invention:

[0020] The present invention reasonably arranges the positions of three PBS sheets and a half glass sheet, so that the receiving light beam and the transmitting light beam of the circulator are input and output in parallel from the front end and the rear end without generating a vertical end, so that the installation metal airtight tubes arranged at the ports of the circulator can be arranged closely and in parallel. Compared with the existing structure of mutually perpendicular metal airtight tubes, the present invention occupies less space and has a more reasonable structure, which is more in line with the arrangement requirements in the communication module, solves the arrangement problem of the transceiver in the optical communication module, and is particularly advantageous for the layout of a multi-channel transceiver integrated device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are 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.

[0022] Figure 1 It is a schematic diagram of the structure optical path of the existing circulator;

[0023] Figure 2 It is a schematic diagram of the structure light path of the present invention;

[0024] Figure 3 A diagram showing the change in polarization angle of the light beam emitted by the present invention;

[0025] Figure 4 A diagram showing a change in polarization state angle of a P polarization state light beam in a received light beam of the present invention;

[0026] Figure 5 This is a diagram showing the change in polarization angle of the S-polarized light beam in the received light beam of the present invention.

[0027] In the above drawings, the corresponding reference numerals are as follows:

[0028] 1-front end, 2-rear end, 3-emitting light beam, 4-receiving light beam, 5-reflecting plate, 6-half glass plate, 6c-half glass plate optical axis, 7-Faraday rotator, 8-first PBS plate, 9-second PBS plate, 10-third PBS plate. DETAILED DESCRIPTION

[0029] In conjunction with the accompanying drawings, the technical solution of the present invention is clearly and completely described through the specific implementation methods of the embodiments of the present invention.

[0030] Embodiment 1:

[0031] A circulator includes a front end 1 and a rear end 2, a transmitting light beam 3 is input from the front end 1 and output from the rear end 2, a receiving light beam 4 is input from the rear end 2 and output from the front end 1, the light beams passing through the front end 1 and the rear end 2 are parallel to each other, and also includes a reflector 5, a half glass plate 6, a magnetic Faraday rotator 7 and a plurality of PBS plates, if the Faraday rotator 7 is not magnetic, an additional magnetic ring is required. By making the light beams passing through the front end 1 and the rear end 2 parallel, it is possible to avoid the generation of vertical ports, thereby avoiding excessive space occupation when installing a metal airtight tube on the subsequent vertical port, which is inconvenient to install in an optical communication module.

[0032] On this basis, if Figure 2As shown, a half glass plate 6 and three PBS plates are arranged in the circulator, and the PBS plates are respectively a first PBS plate 8, a second PBS plate 9 and a third PBS plate 10, and the half glass plate 6 and the three PBS plates are parallel to each other, wherein the first PBS plate 8 and the third PBS plate 10 are located in the front end 1, the second PBS plate 9 and the reflective plate 5 are located in the rear end 2, the half glass plate 6 and the Faraday rotator 7 are arranged between the front end 1 and the rear end 2, the PBS plate and the reflective plate 5 together constitute a beam adjustment area, the emission beam 3 and the incident beam are respectively reflected an even number of times in the beam adjustment area, and the PBS plate and the reflective plate 5 are parallel to each other, so that the reflection of the receiving beam 4 and the emission beam 3 in the beam adjustment area is accurate and controllable, ensuring that the initial incident light and the final outgoing light after the even number of reflections are parallel.

[0033] It should be noted that it is necessary to ensure that the polarization angle between the optical axis of the half-glass 6 and the P-polarized light beam is 22.5°, and the rotation angle of the Faraday rotator 7 is 45°, so that when the light beam passes through the half-glass 6, it is deflected 45° in different directions according to the different initial polarization states of the light beam and the different incident directions. The parallel Faraday rotator 7 is used to fix the polarization angle of the light beam and deflect it 45° in one direction, so that the P-polarized light beam and the S-polarized light beam passing through the half-glass 6 and the Faraday rotator 7 can switch with each other or remain unchanged.

[0034] Furthermore, through the above-mentioned setting, the emission light beam 3 can be limited in advance to a P-polarized light beam by setting a half glass slide 6 before the emission light beam 3 enters the light beam adjustment zone. Since the P-polarized light beam can directly pass through the PBS sheet, the number of reflections of the emission light beam 3 in the beam adjustment zone can be reduced, thereby better controlling the output position of the emission light beam 3.

[0035] Specifically, Figure 3 As shown, the emission light beam 3 input from the front end 1 is a P-polarized light beam, which directly passes through the first PBS plate 8, and then passes through the Faraday rotator plate 7 and the half glass plate 6 in sequence. The polarization angles of the emission light beam 3 changed by the Faraday rotator plate 7 and the half glass plate 6 are the same in size but opposite in direction, so the polarization angle of the P-polarized light beam remains unchanged in the end. The emission light beam 3 can pass through the first PBS plate 8, the Faraday rotator plate, the half glass plate 6 and the second PBS plate 9 in a straight line in sequence. The incident light and the outgoing light are parallel to each other and there is almost no deviation. The polarization angle of the emission light beam 3 changes as shown in FIG. Figure 3As shown; after the receiving light beam 4 passes through the second PBS sheet 9, polarization separation occurs, and it is divided into P polarized light and S polarized light. The P polarized light beam directly passes through the second PBS sheet 9, and when it passes through the Faraday rotator 7 and the half glass sheet 6 in turn, the magnitude and direction of the changed normal angle of the transmitting light beam 3 are the same, and the P polarized light beam is deflected into an S polarized light beam, and is reflected on the first PBS sheet 8 and the third PBS sheet 10 in turn. The change of its polarization angle is shown in Figure 4 As shown; the S polarized light beam is reflected by the second PBS sheet 9 and the reflector 5, and when it passes through the Faraday rotator 7 and the half glass sheet 6 in sequence, the magnitude and direction of the deflection angle of the emitted light beam 3 are the same, and the S polarized light beam is deflected into a P polarized light beam, and directly passes through the third PBS sheet 10, and finally the S polarized light beam and the P polarized light beam separated by the polarization of the receiving light beam 4 are output from the front end 1 together, and the polarization angle change is shown as follows Figure 5 shown.

[0036] It should be noted that, by reasonably arranging the positions of the PBS sheet and the half glass sheet 6, the receiving light beam 4 and the transmitting light beam 3 of the circulator are input and output in parallel from the front end 1 and the rear end 2, without generating a vertical port, so that the metal airtight tube installed at the port of the circulator can be arranged in parallel next to each other, and although the transmitting light beam 3 is limited to a P-polarized light beam, the P-polarized light beam emitted by this circulator can still be recognized and received by other conventional optical devices, and the receiving light beam 4 input from this circulator is still allowed to be an ordinary light beam, that is, it can completely receive the optical signals of other conventional optical devices, while ensuring the quality of optical communication, changing the layout of the traditional circulator, compared with the existing structure of mutually perpendicular metal airtight tubes, it occupies less space, has a more reasonable structure, and is more in line with the arrangement requirements in the communication module.

[0037] Embodiment 2:

[0038] An optical device, a circulator based on the one described in Example 1, wherein a collimator is provided at the rear end 2 of the circulator, and the collimator is used to input a receiving light beam 4 and output a transmitting light beam 3, and two groups of metal airtight tubes are provided in parallel at the rear end 2 of the circulator, which are used to input the transmitting light beam 3 and output the receiving light beam 4 respectively.

[0039] Specifically, the collimator and the metal airtight tube are respectively arranged in parallel on the rear end 2 and the front end 1. No port is arranged in the vertical direction of the collimator, so that the metal airtight tube installed at the port of the front end 1 of the circulator can be arranged in parallel next to each other. Compared with the existing structure of mutually perpendicular metal airtight tubes, it occupies less space, has a more reasonable structure, and is more in line with the arrangement requirements in the communication module.

[0040] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A circulator, characterized in that: The invention comprises a front end (1) and a rear end (2), wherein an emission light beam (3) is input from the front end (1) and output from the rear end (2), and a receiving light beam (4) is input from the rear end (2) and output from the front end (1), and the light beams passing through the front end (1) and the rear end (2) are parallel to each other, and further comprises a reflection plate (5), a half glass plate (6), a Faraday rotator plate (7) and a plurality of PBS plates.

2. A circulator according to claim 1, characterized in that: The PBS sheet and the reflector sheet (5) are parallel to each other. The PBS sheet comprises a first PBS sheet (8), a second PBS sheet (9) and a third PBS sheet (10). The first PBS sheet (8) and the third PBS sheet (10) are located in the front end (1), the second PBS sheet (9) and the reflector sheet (5) are located in the rear end (2), the half glass sheet (6) and the Faraday rotator sheet (7) are arranged between the front end (1) and the rear end (2), the PBS sheet and the reflector sheet (5) together form a beam adjustment area, and the emitted beam (3) and the incident beam are respectively reflected an even number of times in the beam adjustment area.

3. A circulator according to claim 2, characterized in that: The half glass plate (6) and the Faraday rotator plate (7) are parallel to each other.

4. A circulator according to claim 3, characterized in that: The polarization angle between the optical axis of the half glass (6) and the P polarization state light beam is 22.5°.

5. A circulator according to claim 4, characterized in that: The rotation angle of the Faraday rotator (7) is 45°.

6. A circulator according to claim 5, characterized in that: The emitted light beam (3) is a P-polarized light beam.

7. A circulator according to claim 6, characterized in that: The emission light beam (3) input from the front end (1) passes through the first PBS sheet (8), sequentially passes through the Faraday rotator (7) and the half glass sheet (6), is reflected in the light beam adjustment area and changes its polarization angle, and then passes through the second PBS sheet (9) and is emitted from the rear end (2); the reception light beam (4) input from the rear end (2) passes through the second PBS sheet (9), sequentially passes through the half glass sheet (6) and the Faraday rotator (7), is reflected in the light beam adjustment area and changes its polarization angle, and then passes through the third PBS sheet (10) and is emitted from the front end (1).

8. An optical device, characterized in that: A circulator comprising any one of claims 1 to 7, wherein a collimator is arranged at the rear end (2) of the circulator, and the collimator is used to input a receiving light beam (4) and output a transmitting light beam (3); and two groups of metal airtight tubes are arranged in parallel at the rear end (2) of the circulator, respectively used to input a transmitting light beam (3) and output a receiving light beam (4).

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