阅读说明：本技术 一种光开关 (Optical switch ) 是由 吴砺 徐云兵 王宗源 陈卫民 蔡宏铭 李阳 于 2020-05-28 设计创作，主要内容包括：本发明公开一种光开关,其依序包括三光纤准直器、微透镜、棱镜、1/4波片、22.5°法拉第旋转片和反射镜；所述三光纤准直器包括依序连接在一起的三光纤头、双折射晶体和1/2波片组；所述三光纤头的三根光纤中,其中一根光纤为光输入端,其余两根光纤为光输出端；所述1/4波片的光轴方向与22.5°法拉第旋转片底边之间的角度为22.5度,22.5°法拉第旋转片对单次通过的光信号的偏振光旋转角度为22.5度；通过改变22.5°法拉第旋转片内偏振光偏振态的旋转方向,实现信号光从不同的光输出端间切换。本发明为晶体型光开关,开关速度较快；结构简单,成本低廉；单边出纤,产品体积小。(The invention discloses an optical switch, which sequentially comprises three optical fiber collimators, a micro lens, a prism, an 1/4 wave plate, a 22.5-degree Faraday rotation plate and a reflector; the three-fiber collimator comprises three fiber heads, a birefringent crystal and an 1/2 wave plate group which are sequentially connected together; one of the three optical fibers of the three optical fiber heads is an optical input end, and the other two optical fibers are optical output ends; the angle between the optical axis direction of the 1/4 wave plate and the bottom edge of the 22.5-degree Faraday rotator is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator to the polarized light of the optical signal passing through once is 22.5 degrees; by changing the rotation direction of the polarization state of the polarized light in the 22.5-degree Faraday rotator, the switching of the signal light from different light output ends is realized. The invention is a crystal type photoswitch, the switching speed is fast; the structure is simple, and the cost is low; the single side is used for fiber outlet, and the product volume is small.)

1. An optical switch, characterized by: the optical fiber collimator sequentially comprises three optical fiber collimators, a micro lens, a prism, an 1/4 wave plate, a 22.5-degree Faraday rotation plate and a reflector;

the three-fiber collimator comprises three fiber heads, a birefringent crystal and an 1/2 wave plate group which are sequentially connected together; one of the three optical fibers of the three optical fiber heads is an optical input end, and the other two optical fibers are optical output ends;

the angle between the optical axis direction of the 1/4 wave plate and the bottom edge of the 22.5-degree Faraday rotator is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator to the polarized light of the optical signal passing through once is 22.5 degrees;

by changing the rotation direction of the polarization state of the polarized light in the 22.5-degree Faraday rotator, the switching of the signal light from different light output ends is realized.

2. An optical switch according to claim 1, wherein: the birefringent crystal is a walk-off crystal.

3. An optical switch according to claim 1, wherein: the prism is a Wollaston prism or a Roxiong prism.

4. An optical switch, characterized by: the optical fiber collimator sequentially comprises four optical fiber collimators, a micro lens, a prism, an 1/4 wave plate, a 22.5-degree Faraday rotation plate and a reflector;

the four-fiber collimator comprises four fiber heads, a birefringent crystal and an 1/2 wave plate group which are sequentially connected together; in the four optical fibers of the four optical fiber heads, two optical fibers are light input ends, and the other two optical fibers are light output ends;

the angle between the optical axis direction of the 1/4 wave plate and the bottom edge of the 22.5-degree Faraday rotator is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator to the polarized light of the optical signal passing through once is 22.5 degrees;

by changing the rotation direction of the polarization state of the polarized light in the 22.5-degree Faraday rotator, the switching of the signal light from different light output ends is realized.

5. An optical switch according to claim 4, wherein: in the 1/2 wave plate group, the optical axis of the left four-plate 1/2 wave plate is in the horizontal direction or the vertical direction, and the optical axis of the right four-plate 1/2 wave plate is 45 degrees to the horizontal direction.

6. An optical switch according to claim 4, wherein: the birefringent crystal is a walk-off crystal.

7. An optical switch according to claim 4, wherein: the prism is a Wollaston prism or a Roxiong prism.

Technical Field

The invention relates to the field of optical fiber communication, in particular to an optical switch.

Background

Aiming at a mechanical optical switch, the switching speed of the switch is slow, basically, the two ends of the switch are provided with optical fibers, and the size of an optical switch device is large. For a crystal type photoswitch, the switching speed is high, but the structure is more complex under the condition of half of the switching speed and the price is higher; and the fiber output mode is basically that the two ends output the fiber, and the volume of the optical switch device is larger.

Disclosure of Invention

The invention aims to provide an optical switch with high speed and small volume.

In order to achieve the purpose, the invention adopts the following technical scheme:

an optical switch comprising, in order, a three-fiber collimator, a microlens, a prism, an 1/4 wave plate, a 22.5 ° faraday rotator plate, and a mirror;

the three-fiber collimator comprises three fiber heads, a birefringent crystal and an 1/2 wave plate group which are sequentially connected together; one of the three optical fibers of the three optical fiber heads is an optical input end, and the other two optical fibers are optical output ends;

the angle between the optical axis direction of the 1/4 wave plate and the bottom edge of the 22.5-degree Faraday rotator is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator to the polarized light of the optical signal passing through once is 22.5 degrees;

by changing the rotation direction of the polarization state of the polarized light in the 22.5-degree Faraday rotator, the switching of the signal light from different light output ends is realized.

Further, the birefringent crystal is a walk-off crystal.

Further, the prism is a Wollaston prism or a Roxiong prism.

An optical switch comprising, in order, four fiber collimators, a microlens, a prism, an 1/4 wave plate, a 22.5 ° faraday rotator plate, and a mirror;

the four-fiber collimator comprises four fiber heads, a birefringent crystal and an 1/2 wave plate group which are sequentially connected together; in the four optical fibers of the four optical fiber heads, two optical fibers are light input ends, and the other two optical fibers are light output ends;

the angle between the optical axis direction of the 1/4 wave plate and the bottom edge of the 22.5-degree Faraday rotator is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator to the polarized light of the optical signal passing through once is 22.5 degrees;

by changing the rotation direction of the polarization state of the polarized light in the 22.5-degree Faraday rotator, the switching of the signal light from different light output ends is realized.

Furthermore, in the 1/2 wave plate group, the optical axis of the left four 1/2 wave plates is in the horizontal direction or the vertical direction, and the optical axis of the right four 1/2 wave plates is 45 ° to the horizontal direction.

Further, the birefringent crystal is a walk-off crystal.

Further, the prism is a Wollaston prism or a Roxiong prism.

By adopting the technology, the invention has the following beneficial effects: .

1. The invention is a crystal type photoswitch, the switching speed is fast;

2. the invention has simple structure and low cost;

3. the invention has single-side fiber output and small product volume.

Drawings

The invention is described in further detail below with reference to the accompanying drawings and the detailed description;

FIG. 1 is a schematic view of example 1 of the present invention;

FIG. 2 is a schematic view of example 2 of the present invention;

FIG. 3 is a diagram of the relationship between the 1/4 wave plate and the 22.5 Faraday rotator plate;

fig. 4 is a schematic optical axis diagram of 1/2 wave plate sets in embodiment 2.

Detailed Description

Example 1

As shown in fig. 1 or fig. 3, the present invention sequentially comprises a three-fiber collimator, a microlens 4, a prism 5, an 1/4 wave plate 6, a 22.5 ° faraday rotator 7 and a reflector 8;

the three-fiber collimator comprises three fiber heads 1, a birefringent crystal 2 and an 1/2 wave plate set 3 which are sequentially connected together; one of the three optical fibers of the three optical fiber head 1 is an optical input end, and the other two optical fibers are optical output ends;

the angle between the optical axis direction of the 1/4 wave plate 6 and the bottom edge of the 22.5-degree Faraday rotator 7 is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator 7 to the polarized light of the optical signal passing through once is 22.5 degrees;

fig. 1 shows a single-sided 1x2 optical switch, i.e. the optical switch switches between ports a- > b and a- > c.

Port a to port b transmission: an optical signal is transmitted into the optical switch of the invention from an optical fiber at the upper left end (port a) through the three optical fiber heads 1, then enters a birefringent (walk-off) crystal, the optical signal is divided into o light and e light which are polarized perpendicular to each other in the birefringent crystal 2, and are spatially separated (separated in a direction perpendicular to the paper surface), then the o light and the e light continue to propagate to reach 1/2 wave plate group 3, the polarization states of the two light beams are changed into the same direction after passing through 1/2 wave plates, then the two light beams enter the microlens 4 together to collimate the two light beams respectively, then the two collimated light beams pass through the prism 5 (Wollaston prism or Rochon prism), then pass through the 1/4 wave plate 6 and the 22.5 DEG Faraday rotator 7(Garnet) after being reflected by the reflector 8, pass through the 22.5 DEG Faraday rotator 7(Garnet) and the 1/4 wave plate 6 again (the rotation direction of the polarization state of the light beams in the Faraday rotator 7 is controlled by the optical switch, the polarization state of two beams of light is kept unchanged after the two beams of light are transmitted and reflected through (twice pass through) a 22.5-degree Faraday rotator 7(Garnet) and an 1/4 wave plate 6, so that the light beam reaches the light path of a port b from the light path of the port a, the reflected light reaches a micro lens 4 after passing through a prism 5 (Wollaston prism 5 or Roandrostane prism 5) again, the reflected light enters a 1/2 wave plate and a birefringent (walk-off) crystal in the middle (port b) of the three-fiber head 1 after being converged by the micro lens 4, and the two beams of light (o light and e light) are combined in the birefringent crystal 2 and then output from an optical fiber of the port b.

Port a to port c transmission: an optical signal is transmitted into the optical switch of the invention from an optical fiber at the upper left end (port a) through the three optical fiber heads 1, then enters a birefringent (walk-off) crystal, the optical signal is divided into o light and e light which are polarized mutually perpendicular in the birefringent crystal 2, and are spatially separated (separated in a direction perpendicular to a paper surface), then the o light and the e light continuously transmit to the 1/2 wave plate group 3, the polarization states of the two light beams are changed into the same direction after passing through the 1/2 wave plate, then the two light beams enter the microlens 4 together to respectively collimate the two light beams, then the two collimated light beams pass through the prism 5 (Wollaston prism 5 or Rochon prism 5), then pass through the 1/4 wave plate 6 and the 22.5 DEG Faraday rotator 7(Garnet) and then pass through the 22.5 DEG Faraday rotator 7(Garnet) and the 1/4 wave plate 6 (the rotation direction of the polarization state of the light beams in the Faraday rotator 7 is controlled by the optical switch Two beams of light are transmitted and reflected through (two times of total) 22.5 DEG Faraday rotator 7(Garnet) and 1/4 wave plate 6, then the polarization state is rotated by 90 DEG, so that the light beam reaches the light path of port c from the light path of port a, the reflected light reaches the micro lens 4 after passing through the prism 5 (Wollaston prism 5 or Rondrost prism 5) again, the reflected light enters the 1/2 wave plate and the birefringent crystal of the upper and lower surfaces (port c) of the three-fiber head 1 after being converged by the micro lens 4, and the two beams of light (o light and e light) are combined in the birefringent crystal 2 and then output from the optical fiber of the port c.

Thus, by controlling different rotation directions of polarized light polarization states in the 22.5 DEG Faraday rotator, the connection switching of the ports a to b or a to c of the optical switch is completed.

Example 2

As shown in fig. 2, fig. 3 or fig. 4, the present invention sequentially comprises four fiber collimators, a microlens 4, a prism 5, an 1/4 wave plate 6, a 22.5 ° faraday rotator 7 and a reflector 8;

the four-fiber collimator comprises four fiber heads, a birefringent crystal 2 and an 1/2 wave plate set 3 which are sequentially connected together; in the four optical fibers of the four optical fiber heads, two optical fibers are light input ends, and the other two optical fibers are light output ends;

the angle between the optical axis direction of the 1/4 wave plate 6 and the bottom edge of the 22.5-degree Faraday rotator 7 is 22.5 degrees, and the rotation angle of the 22.5-degree Faraday rotator 7 to the polarized light of the optical signal passing through once is 22.5 degrees;

in the 1/2 wave plate group 3, the optical axis of the left four-plate 1/2 wave plate is in the horizontal direction or the vertical direction, and the optical axis of the right four-plate 1/2 wave plate is 45 ° to the horizontal direction.

Fig. 2 is a single-sided 2x2 optical switch, i.e. the optical switch switches between ports a- > c & b- > d and a- > d & b- > c.

Transmission of port a- > c & b- > d: the principle is exactly the same as that of embodiment 1 (the rotation direction of the polarization state of the light beam in the faraday rotator 7 is controlled by the optical switch, so that the polarization state of the light signal is kept unchanged after the light signal is transmitted and reflected (twice) through the 22.5 ° faraday rotator 7(Garnet) and the 1/4 wave plate 6, so that the light beam reaches the optical path of the port c from the optical path of the port a, and reaches the optical path of the port d from the optical path of the port b).

Transmission of port a- > d & b- > c: the principle is exactly the same as that of embodiment 1 (the rotation direction of the polarization state of the light beam in the faraday rotator 7 is controlled by the optical switch, so that the polarization state of the light signal is rotated by 90 ° after the light signal is transmitted and reflected (passes through twice) through the 22.5 ° faraday rotator 7(Garnet) and the 1/4 wave plate 6, so that the light beam reaches the optical path of the port d from the optical path of the port a, and reaches the optical path of the port c from the optical path of the port b).

Thus, by controlling different rotation directions of polarized light polarization states in the 22.5 DEG Faraday rotator, the connection switching of ports a to c & b to d and ports a to d & b to c of the optical switch is completed.

While the invention has been described in connection with the above embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, which are illustrative and not restrictive, and that those skilled in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.