CN103424896B - Optical path control device - Google Patents

Abstract

The present invention provides an optical path control device, including a first optical fiber collimator and a second optical fiber collimator, and a first light splitting and combining device, a second optical fiber collimator and The half-wave plate assembly, the optical rotation assembly, the second half-wave plate assembly, and the second light splitting and combining device, wherein the outer ends of the first fiber collimator and the second fiber collimator are respectively provided with side-by-side A plurality of ports, the plurality of ports constitute the ports of more than two optical path devices, the number of ports of each optical path device is more than three, and each optical path device includes at least one port located at the outer end of the first fiber collimator and located at the At least one port at the outer end of the second fiber collimator. The optical path control device provided by the invention can realize the integration of the optical circulator and the magneto-optical switch, and reduce its production cost.

Description

Optical path control device

technical field

The invention relates to an optical device used in an optical fiber communication system, in particular to an optical path control device.

Background technique

Optical path control devices, such as optical circulators and magneto-optical switches, are widely used in modern optical fiber communication systems. Both the optical circulator and the magneto-optical switch are used to control the optical path, such as controlling the incident light beam from one port to exit from another designated port, so as to realize the control and selection of the optical path.

An optical circulator is an optical passive device with an irreversible optical path. The most typical common applications are three-port optical circulators and four-port optical circulators. Since the light path of the optical circulator is incident from the first port to the exit of the second port, and from the incident of the second port to the exit of the third port, and the light beam incident from the second port cannot exit from the first port, the light beam incident from the third port Beams cannot emerge from the second port.

The early optical circulators were mainly used in two-way optical communication, the first port was used as the port for uploading signals, and the third port was used as a port for downloading signals. Based on the unique functions of the optical circulator, it has been applied in wavelength division multiplexing (WDM), erbium-doped fiber amplifier (EDFA), dispersion compensation and optical time domain reflectometer of optical network.

However, due to the high manufacturing cost of the optical circulator, most equipment manufacturers choose it cautiously, so the optical circulator has not been widely used for many years. Due to the explosive growth of network communication capacity and network data transmission speed in recent years, equipment manufacturers have found that the unique functions of optical circulators cannot be replaced by other forms of device equipment or the cost of replacement is even higher. The demand for optical circulators has suddenly increased. There is also an increasing demand for low-cost optical circulators.

After decades of development, the structure of the optical circulator has been continuously improved, such as the US patent US5930039 and the announcement number is The Chinese patents of CN2487161Y and CN1356786A disclose optical circulators with different structures. The optical circulators disclosed in the above patents are currently very mature optical circulators. Most of the technical means are to use different optical elements to couple light to the dual-fiber collimator Inside.

However, with the development of communication technology, from the consideration of cost reduction and space size reduction, the array design or integrated design of optical circulators is obviously an urgent trend. The related patents are disclosed in US20020097957A1 and US6580842B1 . In addition, US patent application US20020097957A1 discloses an optical circulator array using a microlens array.

As shown in Figure 1, the optical circulator array has collimator arrays 11,21, and is provided with wedge-corner prisms 12,20, and the inner side of wedge-corner prisms 12,20 is provided with birefringent crystals 13,19, and birefringent crystals 13 The inboards of , 19 are provided with Faraday rotators 14,17, and the inboards of Faraday rotators 14,17 are provided with half-wave plates 15,18, and what is positioned between half-wave plates 15 and Faraday rotators 17 is to realize the birefringence crystal of annular light path 16.

The collimator arrays 11 and 21 are provided with multiple ports, such as ports 1A, 2A, 1B, 2B, 3A, 3B, etc., and each port is an independent collimation unit. Compared with the optical circulators disclosed in US Patent No. 5930039 and Chinese Patents CN2487161Y and CN1356786A, the optical circulator shown in Fig. 1 removes the optical components coupled with the dual-fiber collimator. In order to reduce the influence of reflected light from the optical components, but increases wedge-corner prism. Although this design is suitable for large-scale manufacturing, it uses more expensive crystal materials, resulting in high production costs for optical circulators.

As another example, U.S. Patent US6580842B1 discloses another optical circulator array, see Fig. 2, the array adopts planar optical waveguide technology, and integrates the non-reciprocal unit for realizing the ring optical path on a substrate 31, and couples through the optical fiber array , a plurality of circulator units are arranged on the substrate 31 . A plurality of optical waveguides 38 are arranged on the substrate 31, and a plurality of grooves 32, 33, 34, 35 are engraved on the substrate 31 by means of modern precision semiconductor technology, and the non-reciprocal unit realizing the optical circulator is installed in the groove 32 , 33, 34, 35. Moreover, the optical waveguide 38 and the non-reciprocal unit of the circulator are bonded with a refractive index matching adhesive.

However, the non-reciprocal optical circulator unit of the optical circulator array is still made of expensive crystal material, and at the same time, a plurality of grooves 32, 33, 34, 35 need to be etched on the substrate 31, which affects the processing accuracy. The process requirements are also high, resulting in extremely high production costs of the optical circulator array.

Magneto-optical switches are used to realize the selective switching of light beams between one input fiber and multiple output fibers or between multiple input fibers and one output fiber. It is mainly used in modern optical fiber communication industry, instrumentation industry and national defense industry.

At present, the most mature magneto-optical switch technology is a magneto-optic switch realized by using a magnetic field to control the rotation of a magneto-optic crystal in a circular optical path. For example, the utility model with the notification number CN2896323Y discloses an invention named "compact structure 1×2 magneto-optical switch". The magneto-optic switch has a single-fiber collimator, and an optical fiber , and the first birefringent crystal, the first half-wave plate component, the first Faraday rotator, the birefringent crystal light guide, the birefringent crystal beam deflector, the second Faraday rotator, the second Two half-wave plate components, a second birefringent crystal, and a double-fiber collimator, two parallel optical fibers are installed in the double-fiber collimator, and magnetic field generating devices are respectively arranged outside the two Faraday rotators for feeding Faraday The rotating plate is loaded with a variable magnetic field, which changes the direction of the light path.

However, the existing magneto-optical switches also have the problem of insufficient integration, which leads to an excessively bulky communication device and is not conducive to reducing the production cost of the communication device.

Contents of the invention

The main purpose of the present invention is to provide an optical path control device with small volume and high integration degree.

In order to achieve the above-mentioned main purpose, the optical path control device provided by the present invention includes a first fiber collimator and a second fiber collimator, and a first branch is arranged between the first fiber collimator and the second fiber collimator. The photosynthetic optical device, the first half-wave plate assembly, the optical rotation assembly, the second half-wave plate assembly, and the second light-splitting and combining optical device, wherein the outer ends of the first fiber collimator and the outer ends of the second fiber collimator are respectively There are multiple ports arranged side by side, the multiple ports constitute the ports of two or more optical path devices, the number of ports of each optical path device is more than three, and each optical path device includes a collimator located in the first optical fiber At least one port at the outer end of the collimator and at least one port at the outer end of the second fiber collimator.

It can be seen from the above scheme that since multiple ports are integrated in each fiber collimator, and the two optical path devices respectively use these ports as the incident port or exit port of the light beam, so that multiple optical path devices can be integrated in the same optical path control device The functions of light beam transmission are respectively realized, thereby realizing the integration of optical circulators or magneto-optical switches, reducing the production cost and volume of optical path control devices.

A preferred solution is that the optical rotation assembly has a refraction device and two Faraday rotators located on both sides of the refraction device, or the optical rotation assembly has two refraction devices and two Faraday rotators arranged at intervals.

It can be seen that the polarization state of the light beam is rotated by the Faraday rotator, and the propagation direction of the light beam is deflected by the refraction device, so that the direction of the light beam can be controlled simply and effectively.

A further solution is that the optical rotation assembly also has a magnetic field generating device for applying a magnetic field with a fixed direction to the Faraday rotator.

It can be seen that the Faraday rotator is loaded with a magnetic field in a fixed direction through the magnetic field generating device, and the optical path control device realizes the function of the optical circulator.

Optionally, the optical rotation assembly also has a magnetic field generating device for applying a variable direction magnetic field to the Faraday rotator.

It can be seen that by changing the direction of the magnetic field generated by the magnetic field generating device and controlling the polarization direction of the light beam, the optical path control device can be used as a magneto-optical switch.

A further solution is that the number of ports of each optical path device is three, and the two ports of each optical path device are located at the outer end of the first fiber collimator, and the other port of each optical path device is located at the second optical fiber the outer end of the collimator.

It can be seen that the beams of the two optical path devices will not interfere with each other when they are transmitted in the fiber collimator and other devices. Integration of optical path control devices.

Description of drawings

FIG. 1 is a schematic structural diagram of an existing optical circulator array.

Fig. 2 is a schematic structural diagram of another conventional optical circulator array.

Fig. 3 is a schematic structural diagram of the first embodiment of the present invention.

Fig. 4 is an enlarged schematic diagram of the structure of two fiber collimators in the first embodiment of the present invention.

Fig. 5 is a top view of the optical structure of the first embodiment of the present invention.

Fig. 6 is an enlarged top view of the optical structure of the optical rotation assembly in the first embodiment of the present invention.

Fig. 7 is a schematic diagram of the polarization state of the light beam when the first embodiment of the present invention is in operation.

Fig. 8 is a structural diagram of a first alternative scheme of the refraction device in the first embodiment of the present invention.

Fig. 9 is a structural diagram of a second alternative of the refraction device in the first embodiment of the present invention.

Fig. 10 is a top view of the optical structure of the second embodiment of the present invention.

Fig. 11 is a top view of the optical structure of the third embodiment of the present invention.

Fig. 12 is an enlarged schematic diagram of the structure of two fiber collimators in the third embodiment of the present invention.

Fig. 13 is a top view of the optical structure of the fourth embodiment of the present invention.

Fig. 14 is an enlarged schematic diagram of the structure of two fiber collimators in the fourth embodiment of the present invention.

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

detailed description

The optical path control device of the present invention is an optical circulator array or a magneto-optical switch array, that is, the functions of multiple optical circulators or multiple magneto-optical switches are realized in one optical path control device, thereby realizing the integration of optical circulators or magneto-optical switches change. Since each optical path control device can realize the function of two or more optical circulators or magneto-optical switches, the optical path device referred to in the present invention is an optical circulator or a magneto-optical switch. The optical path control device of the present invention will be described below by taking an optical circulator array as an example.

First embodiment:

Referring to FIG. 3 , the optical path control device of this embodiment is an optical circulator array, which has a fiber collimator 101 located at one end of the device, and four optical fibers 116 are installed in the fiber collimator 101 . Another fiber collimator 111 is provided at the other end of the device, and two optical fibers 117 are installed in the fiber collimator 111 .

One end of each optical fiber 116, 117 protrudes out of the fiber collimator 101, 111, so each optical fiber 116, 117 respectively constitutes a light beam incident and output port. In this embodiment, 1A, 2A, 3A, 1B, 2B, and 3B are used to mark six ports, wherein ports 1A, 2A, and 3A are the three ports that constitute the first optical path device, and ports 1B, 2B, and 3B are the three ports that constitute the first optical path device. Three ports of the second light path device.

It can be seen that the optical path control device of this embodiment can realize the functions of two three-port optical circulators, the three ports of the first optical circulator are 1A, 2A, and 3A respectively, and the three ports of the second optical circulator They are 1B, 2B, 3B respectively. This requires a beam entering port 1A to exit port 2A, and a beam entering port 2A exiting port 3A, not allowing a beam entering port 2A to exit port 1A, nor allowing a beam entering 3A to exit port 2A. Similarly, a beam entering port 1B exits port 2B, and a beam entering port 2B exits port 3B, a beam entering port 2B is not allowed to exit port 1B, and a beam entering 3B and exiting port 2B is not allowed .

It can be seen from FIG. 4 that the fiber collimator 101 is arranged opposite to the fiber collimator 111, and the four optical fibers 117 in the fiber collimator 101 are arranged side by side, arranged in a straight line, and along the axis of the fiber collimator 101 Symmetrical arrangement. The adjacent two of the four optical fibers 116 are closely arranged, and the gap between the adjacent two optical fibers 116 is very small.

The two optical fibers 117 in the fiber collimator 111 are also arranged side by side, arranged in a straight line, and symmetrically arranged along its axis in the fiber collimator 111, and the two optical fibers 117 are also closely arranged.

And, the two ports 1A, 3A as the first optical circulator are located at the outer end of the fiber collimator 101, and the two ports 1B, 3B as the second optical circulator are also located at the outer end of the fiber collimator 101 , and the four ports of the two optical circulators are arranged at intervals, that is, one port 3A of the first optical circulator is located between the two ports 1B, 3B of the second optical circulator, and one port 3A of the second optical circulator Port 1B is located between the two ports 1A, 3A of the first optical circulator.

Referring back to FIG. 3 , between the fiber collimator 101 and the fiber collimator 111 , a birefringent crystal 102 , a half-wave plate component, an optical rotation component, another half-wave plate component, and a birefringent crystal 110 are arranged in sequence along the optical path. Both the birefringent crystals 102 and 110 are light splitting and combining devices of this embodiment, and are used for splitting or combining light beams. A beam of light passing through the birefringent crystal 102 or 110 will be split into two beams whose polarization states are perpendicular to each other. For example, two beams of light beams with mutually perpendicular polarization states can be combined into one beam after passing through the birefringent crystal 102 or 110 .

In this embodiment, the half-wave plate component located next to the birefringent crystal 102 has a half-wave plate 103 , and the half-wave plate 103 is located on one of the optical paths of the two beams emitted from the birefringent crystal 102 . It can be seen from FIG. 3 that the half-wave plate 103 is located near the lower end of the birefringent crystal 102 .

The half-wave plate component located next to the birefringent crystal 110 has a half-wave plate 109 and a compensation plate 108. The half-wave plate 109 is located on the optical path of the same light beam as the half-wave plate 103, and the compensation plate 108 is located on the same path as the half-wave plate 109. The light path where the other light beam opposite to the light beam is located. It can be seen from FIG. 3 that the half-wave plate 109 is located near the lower end of the birefringent crystal 110 , and the compensation plate 108 is located near the upper end of the birefringent crystal 110 .

The half-wave plates 103, 109 have a phase retardation effect on the light beam, and the phase of the polarized light beam will be delayed after passing through the half-wave plate 103, 109, thereby changing the polarization state of the polarized light beam. In this embodiment, after the light beam passes through the half-wave plates 103 and 109, the phase delay is half a phase, and the polarization direction will be deflected by 90°.

In this embodiment, by setting the angle of the optical axis of the half-wave plates 103, 109 and the angle of the polarization direction of the linearly polarized light incident on the half-wave plates 103, 109, the half-wave plates 103, 109 can realize the linearly polarized light. 90° rotation of the polarization state. In other applications, by changing the optical axis direction of the half-wave plate, the rotation angle of the polarization direction of the linearly polarized light after passing through the half-wave plate is not necessarily 90°, but other angles.

The compensation sheet 108 plays a role of polarization mode dispersion compensation in the optical path control device of this embodiment.

The optical rotation component has a refraction device. In this embodiment, the refraction device is composed of two Wollaston prisms 105, 106, and the optical axes of the two Wollaston prisms 105, 106 are perpendicular to each other. Faraday rotators 104, 107 are respectively arranged at both ends of the Wollaston prisms 105, 106, wherein the Faraday rotator 104 is arranged on the side close to the half-wave plate 103, and the Faraday rotator 107 is arranged on the side close to the half-wave plate 109 side.

Magnetic field generators 112 and 113 are provided outside the Faraday rotators 104 and 107 for applying a magnetic field in a fixed direction to the Faraday rotators 104 and 107. Therefore, the magnetic field generators 112 and 113 can be implemented using permanent magnets.

Referring to FIG. 5 , in this embodiment, a solid line is used to represent the optical path of the first optical circulator, and a dotted line is used to represent the optical path of the second optical circulator. The light beam incident from the port 1A with any polarization state and any polarization direction passes through the fiber collimator 101 and then enters the birefringent crystal 102, where it is decomposed into two light beams whose polarization states are perpendicular to each other. The optical axis of the birefringent crystal 102 is in the XOY plane, and forms an included angle of 45° with both the X axis and the Y axis. A beam formed by decomposition is extraordinary light, whose polarization direction is parallel to the Y axis, and exits from the side close to the upper end of the birefringent crystal 102 . The other beam is ordinary light, whose polarization direction is parallel to the X-axis, and exits from the side close to the lower end of the birefringent crystal 102 .

The polarization direction of the beam in each optical device of the optical path control device is shown in Figure 7, where the upper row in Figure 7 indicates the change of the polarization direction from the incident beam from port 1A or 1B to port 2A or 2B, and the lower row indicates The polarization direction changes during the incident beam from port 2A or 2B to port 3A or 3B. The arrows in Figure 7 indicate the transmission direction of the beam, and the uppermost number in Figure 7 is the number of the corresponding optical device.

A beam of light emitted from the birefringent crystal 102 directly enters the Faraday rotator plate 104 . The other beam enters the Faraday rotator 104 after passing through the half-wave plate 103 , so the polarization directions of the two beams before entering the Faraday rotator 104 are the same. After the two beams pass through the Faraday rotator 40, their polarization directions are rotated by 45°, and the polarization directions are rotated clockwise by 45° in the YOZ plane.

In this embodiment, the direction in which the magnetic field generating device 112 applies a magnetic field to the Faraday rotator 104 is fixed, so the direction in which the polarization direction of the light beam rotates is also fixed. After the two beams are incident on the Wollaston prisms 105 and 106, the direction of propagation is deflected, that is, they are translated a certain distance in the negative direction of the Z axis in the XOZ plane. Subsequently, after the two beams pass through the Faraday rotator 107, the polarization state is deflected again, and will continue to rotate clockwise by 45° in the YOZ plane, and the polarization directions of the two beams are parallel to the Z axis.

Then, when one of the light beams passes through the compensation plate 108, the polarization state will not change, but only a phase delay will occur. The other beam passes through the half-wave plate 109, and its polarization direction is rotated by 90°. At this time, the polarization directions of the two beams are perpendicular to each other. Finally, the two beams of light are incident on the birefringent crystal 110 and combined, and exit from the port 2A of the fiber collimator 111 .

The incident beam from port 2A passes through the birefringent crystal 110 and is decomposed into two beams whose polarization directions are perpendicular to each other. After the two beams pass through the Faraday rotator 107, the polarization direction is rotated by 45°, and the two beams are incident on the Wollaston Afterwards, the prisms 106 and 105 translate a certain distance in the negative direction of the Z axis in the XOZ plane. After the two light beams pass through the Faraday rotator 104 , the polarization directions are rotated by 45° again, and combined in the birefringent crystal 102 , the light exits from the port 3A. It can be seen that the light beam incident from port 2A does not exit from port 1A, but exits from port 3A, thereby realizing a circular optical path.

The process of the incident light beam from port 1B to port 2B, and the process of the incident light beam from port 2B to port 3B are the same as the above process, and will not be repeated.

However, if a beam is incident on port 1A and port 1B at the same time, the incident beam from port 1A and port 1B will intersect on the adjoining surfaces of Wollaston prisms 105, 106, as shown in FIG. 6 . The light beam of the first optical circulator close to the positive direction of the Z axis passes through the adjoining surfaces of the Wollaston prisms 105 and 106, and propagates along the negative direction close to the Z axis, while the light beam of the second optical circulator close to the negative direction of the Z axis originally travels After passing through the adjacent surfaces of the Wollaston prisms 105 and 106, the light beams of the detector propagate along the positive direction close to the Z-axis, thereby arriving at the ports 1A and 1B respectively.

This is because the angle between the propagating direction of the light beam incident from the port 1A and the adjoining surfaces of the Wollaston prisms 105 and 106 is relatively large, and the angle at which the light beam is deflected on the adjoining surfaces is also relatively large. The angle between the transmission direction of the incident light beam from port 1B and the adjacent surfaces of Wollaston prisms 105 and 106 is relatively small, and the deflection angle of the light beam on the adjacent surfaces is also small, which is similar to the refraction principle of light , there is a proportional relationship between the angle of incidence and the angle of refraction.

However, the transmission of the two crossed beams will not interfere with each other, so the quality of beam transmission will not be affected.

In this way, multiple ports of two optical circulators are integrated in one optical path control device to realize the functions of the two optical circulators, realize the integration of the optical circulators, and reduce the production cost of the optical circulators.

Of course, the Wollaston prisms 105, 106 in the optical rotation assembly can be replaced by other devices. As shown in FIG. The optical axes of the prisms are perpendicular to each other. Or, as shown in Figure 9, the refraction device is replaced by two adjacent wedge prisms 135,136, and the optical axes of the two wedge prisms 135,136 are also perpendicular to each other, and it can also be a Wollaston prism 105, Any one of the prisms in 106 is made of isotropic optically transparent material.

In the optical rotation assembly, two Faraday rotators 104, 107 and two Wollaston prisms 105, 106 can be arranged at intervals, that is, a Faraday rotator 104, a Wollaston prism 105, and a Faraday rotator can be arranged in sequence along the direction of the optical path. 107 and the Wollaston prism 106. At this time, the optical axes of the Wollaston prisms 105 and 106 are different from those of the above-mentioned embodiments.

In addition, when the optical path control device realizes the functions of two magneto-optical switches, the structure is basically the same as the above-mentioned structure, except that the magnetic field generating devices 112 and 113 do not generate a magnetic field with a fixed magnetic field direction, but a magnetic field with a variable magnetic field direction. At this time, each magnetic field generating device includes an annular iron core, on which a coil is wound, and DC currents in different directions are applied to the coil to generate magnetic fields with different polarities on the iron core.

When used as a magneto-optical switch, the light beam is incident from port 2A, and optionally exits from port 1A or port 3A, depending on the direction of the magnetic field generated by the magnetic field generating device. In addition, the light beam can also enter from port 2B and optionally exit from port 1B or port 3B. In this way, the optical path control device can realize the functions of two magneto-optical switches, thereby realizing the integration of the magneto-optic switches.

Second embodiment:

Referring to Fig. 10, the structure of this embodiment is basically the same as that of the first embodiment, which has a fiber collimator 201 and a fiber collimator 211, and double Refractive crystal 202 , half-wave plate 203 , Faraday rotator 204 , Wollaston prisms 205 , 206 , Faraday rotator 207 , compensation plate 208 and birefringent crystal 210 , and another half-wave plate is arranged below the compensation plate 208 .

Different from the first embodiment, in this embodiment, six optical fibers are installed in the fiber collimator 201, and three optical fibers are installed in the fiber collimator 211, so the optical path control device realizes the functions of three optical circulators. Among them, ports 1A, 2A, and 3A are the three ports of the first optical circulator, ports 1B, 2B, and 3B are the three ports of the second optical circulator, and ports 1C, 2C, and 3C are the third optical circulator. There are three ports of the optical fiber collimator, the ports 1A, 3A, 1B, 3B, 1C, and 3C are located at the outer end of the fiber collimator 201, the six ports are arranged side by side, and the ports 2A, 2B, and 2C are located at the outer end of the optical fiber collimator 211 , the three ports are also arranged side by side.

The light beam incident from port 1A to port 2A, the light beam from port 1B to port 2B, and the light beam from port 1C to port 2C cross on the adjacent surfaces of Wollaston prisms 205 and 206, but are mutually Will not interfere with each other, thus ensuring the quality of beam transmission.

Third embodiment:

Referring to Fig. 11, the structure of this embodiment is basically the same as that of the first embodiment, which has a fiber collimator 301 and a fiber collimator 311, and double Refractive crystal 302 , half-wave plate 303 , Faraday rotator 304 , Wollaston prisms 305 , 306 , Faraday rotator 307 , compensation plate 308 and birefringent crystal 310 , and another half-wave plate is arranged below the compensation plate 308 .

Four optical fibers arranged side by side are installed in the fiber collimator 301, and two optical fibers arranged side by side are installed in the fiber collimator 211, so the optical path control device realizes the function of two optical circulators. Wherein, ports 1A, 2A, and 3A are three ports of the first optical circulator, and ports 1B, 2B, and 3B are three ports of the second optical circulator.

Different from the first embodiment, the two optical fibers installed in the fiber collimator 311 are not adjacent, as shown in Figure 12, there is a certain distance between the two optical fibers 322 installed in the fiber collimator 311 , and the four optical fibers 320 installed in the fiber collimator 301 are closely arranged, that is, two adjacent optical fibers 320 are adjacent.

Because there is a certain distance between port 2A and port 2B, the two ports 1A, 3A of the first optical circulator and the two ports 1B, 3B of the second optical circulator are not arranged at intervals, and the first optical circulator The two ports 1A, 3A are arranged adjacently, and the two ports 1B, 3B of the second optical circulator are also arranged adjacently.

Similarly, the beam incident from port 1A to port 2A and the beam incident from port 1B to port 2B cross on the adjacent surfaces of Wollaston prisms 305 and 306, but they will not interfere with each other, so as to ensure that the beams The quality of the transmission.

In this embodiment, the axis of the optical fiber 320 and the axis of the fiber collimator 301 are not arranged in parallel, but have a certain angle, so as to ensure that the beam incident from port 1A can exit from port 2A, and the beam incident from port 2A Capable of exiting port 3A.

Fourth embodiment:

Referring to Fig. 13, the present embodiment has a fiber collimator 401 and a fiber collimator 411, and a birefringent crystal 402, a half-wave plate 403, and a Faraday rotator 404 are sequentially arranged between the fiber collimator 401 and the fiber collimator 411 , Wollaston prisms 405, 406, Faraday rotator plate 407, compensation plate 408 and birefringent crystal 410, and another half-wave plate is arranged under the compensation plate 408.

Referring to FIG. 14 , three optical fibers 420 and 422 are installed in the fiber collimators 401 and 411 respectively. The three optical fibers 420 are arranged side by side in the fiber collimator 401 , and two adjacent fibers 420 are adjacent to each other. The three optical fibers 422 are also arranged side by side in the fiber collimator 411 , and two adjacent optical fibers 422 are adjacent to each other.

Three ports are respectively formed outside the fiber collimator 401, 411, which are respectively ports 1A, 2B, and 3A outside the fiber collimator 401 and ports 1B, 2A, and 3B outside the fiber collimator 411, wherein port 1A , 2A, and 3A are the three ports of the first optical circulator, and ports 1B, 2B, and 3B are the three ports of the second optical circulator, so this embodiment can realize the functions of two optical circulators.

It can be seen from Fig. 14 that, outside the fiber collimator 401, the port 2B of the second optical circulator is located between the ports 1A and 3A at both ends of the first optical circulator, and outside the fiber collimator 411, the first optical circulator Port 2A of the optical circulator is located between ports 1B and 3B at both ends of the second optical circulator. This symmetrical structure realizes the integration of the optical circulator, reduces the volume of the optical circulator array, and reduces the production cost of the optical circulator.

Of course, the above-mentioned embodiment is only the preferred embodiment of the present invention, and more changes can be made during practical application. For example, in the second, third, and fourth embodiments, permanent magnets are arranged outside the Faraday rotator for Generates a magnetic field in a fixed direction. If the direction of the magnetic field generated by the magnetic field generating device is a variable direction magnetic field, then the optical path control device in the three embodiments is a magneto-optical switch array.

In addition, the present invention can also be applied to a four-port optical circulator array. For example, in the first embodiment, four optical fibers are installed in each optical fiber collimator, that is, two more optical fibers are arranged side by side on the optical fiber collimator 111. Two optical circulators with four ports can be realized by adding two ports on one side of the port 2A.

In addition, a polarizing beam splitting prism (PBS) can be used instead of a birefringent crystal as a light splitting and combining device, and such a change can also achieve the purpose of the present invention.

When the optical path control device is used as an optical circulator array, the two Faraday rotators of the optical rotation component can be magneto-optical crystals with magnetic domain locking. In this way, there is no need to add a magnetic field generating device with a fixed direction outside the Faraday rotator.

In the refraction device of the above-mentioned embodiment, the two prisms can be prisms made of optical birefringent materials, or one of the prisms can be made of birefringent materials, and the other prism can be made of isotropic optical light-transmitting materials. made.

Finally, it should be emphasized that the present invention is not limited to the above-mentioned embodiments, and changes such as changes in the refraction device and specific components of the optical rotation component should also be included in the protection scope of the claims of the present invention.

Claims (9)

1. Optical path control devices, including A first optical fiber collimator and a second optical fiber collimator, a first light splitting and combining device, a first half-wave plate assembly, An optical rotation component, a second half-wave plate component, and a second light splitting and combining device; It is characterized by: The outer end of the first fiber collimator and the outer end of the second fiber collimator are respectively provided with a plurality of ports arranged side by side, and the plurality of ports constitute the ports of at least two optical path devices, each of which The number of the ports of the optical path device is at least three, and each of the optical path devices includes at least one port located at the outer end of the first fiber collimator and at least one port located at the outer end of the second fiber collimator at least one of said ports; The optical rotation assembly has a refraction device and two Faraday rotators located on both sides of the refraction device, wherein a plurality of the ports are arranged in a straight line in the corresponding fiber collimator, and in the fiber collimator along its Axisymmetric arrangement. 2. The optical path control device according to claim 1, characterized in that: The optical rotation assembly has two refraction devices and two Faraday rotators arranged at intervals. 3. The optical path control device according to claim 1 or 2, characterized in that: The optical rotation assembly also has a magnetic field generating device for applying a magnetic field with a fixed direction to the Faraday rotator. 4. The optical path control device according to claim 1 or 2, characterized in that: The optical rotation assembly also has a magnetic field generating device for applying a variable direction magnetic field to the Faraday rotator. 5. The optical path control device according to claim 1 or 2, characterized in that: The number of the ports of each of the optical path devices is three, and the two ports of each of the optical path devices are located at the outer end of the first fiber collimator, and the other of each of the optical path devices One of said ports is located at the outer end of said second fiber collimator. 6. The optical path control device according to claim 5, characterized in that: The ports of the plurality of optical path devices located at the outer end of the first fiber collimator are arranged at intervals. 7. The optical path control device according to claim 5, characterized in that: The two ports of the same optical path device located at the outer end of the first fiber collimator are adjacently arranged. 8. The optical path control device according to claim 1 or 2, characterized in that: The number of the ports of each optical path device is three, the two ports of the first optical path device are located at the outer end of the first optical fiber collimator, and the other of the first optical path device The port is located at the outer end of the second fiber collimator; The two ports of the second optical path device are located at the outer end of the second optical fiber collimator, and the other port of the second optical path device is located at the outer end of the first optical fiber collimator. 9. The optical path control device according to claim 1 or 2, characterized in that: The refraction device is a Wollaston prism or a Rochon prism or a pair of adjacent wedge-shaped birefringent crystals.