Light splitting device

Abstract

The light splitting device comprises a first light splitting piece, a first wave plate, a magneto-optical crystal, a Wollaston prism, a second wave plate, a third wave plate and a second light combining piece which are arranged along a light path, the first wave plate is arranged on one light path after light splitting of the first light splitting part so as to ensure that the polarization state of linearly polarized light input into the magneto-optical crystal is kept consistent; the second wave plate and the third wave plate are respectively arranged in one of emergent light paths of the Wollaston prism; and a coil is arranged outside the magneto-optical crystal. According to the utility model, through currents of different magnitudes, the coil generates magnetic fields of different magnitudes, the magnetic fields of different magnitudes generate different rotation angles, the different rotation angles correspond to different sin2theta and cos2theta, and furthermore, through the Wollaston prism, two polarization states have light splitting of different proportions. And two beams of light with different splitting ratios are formed after beam combination.

Description

Technical Field

[0001] The utility model relates to the technical field of optics, in particular to a light splitting device. Background Art

[0002] With the increasing popularity of fiber optic networks, especially fiber-to-the-home (FTTH) and fiber-optic cable television (CATV), the demand for optical splitters is growing. Currently, typical fiber-optic or waveguide optical splitters can only provide fixed splitting ratios. With the development of telecommunications services, telecom service providers can control a portion of schedulable resources at multiple or even every site, significantly reducing the excess optical power of each branch. This saves a considerable amount of optical amplifiers, reduces overall system costs and operating expenses, and thus improves service reliability and flexibility, increasing revenue. Therefore, tunable optical splitters are used. Typical tunable optical splitters use a method of applying stress to the fused cone of an ordinary fiber coupler to change the splitting ratio between the two outputs. However, this method has the disadvantages of a small adjustable range, low control accuracy, and limited application value.

[0003] Currently available tunable beam splitters consist of a polarization controller and a birefringent crystal. Linearly polarized light enters the polarization controller, which changes its polarization state before exiting. The beam then reaches the birefringent crystal, which splits it into two beams with perpendicular polarization directions. This tunable beam splitter uses the polarization controller to change the polarization state of the incident light to control the splitting ratio between the two beams. Utility Model Content

[0004] In order to solve the above problems in the prior art, the utility model provides a spectrometer.

[0005] In order to achieve the above-mentioned purpose, the main technical solutions adopted by this utility model include:

[0006] A spectroscopic device comprises a first spectroscopic element, a first wave plate, a magneto-optical crystal, a Wollaston prism, a second wave plate, a third wave plate, and a second light combining element arranged along an optical path; the first wave plate is arranged on one of the optical paths after light is split by the first spectroscopic element to ensure that the polarization state of the linearly polarized light input into the magneto-optical crystal remains consistent; the second wave plate and the third wave plate are each arranged on one of the output optical paths of the Wollaston prism; and a coil is provided outside the magneto-optical crystal.

[0007] A spectroscopic device, characterized in that it includes a first spectroscopic element, a first wave plate, a magneto-optical crystal, a Wollaston prism, a second wave plate, a third wave plate, and a second light combining element arranged along an optical path; the first wave plate is arranged on one of the optical paths after the first spectroscopic element splits the light to ensure that the polarization state of the linearly polarized light input into the magneto-optical crystal remains consistent; the second wave plate and the third wave plate are each arranged on one of the output optical paths of the Wollaston prism; and the magneto-optical crystal is a Faraday rotator crystal with its own magnetism.

[0008] Furthermore, the first beam splitter is connected to a single-fiber collimator for inputting light.

[0009] Furthermore, the optical rotation angle of the first wave plate is 90 degrees.

[0010] Furthermore, the optical rotation angles of the second wave plate and the third wave plate are 90 degrees.

[0011] Furthermore, the second light combiner is connected to a dual-fiber collimator for receiving output light.

[0012] Furthermore, the first light splitting element and the second light combining element are both displacement plates.

[0013] Furthermore, the first light splitting element and the second light combining element are both birefringent crystals.

[0014] The beneficial effect of the present invention is that the coil generates magnetic fields of different sizes through currents of different sizes, and magnetic fields of different sizes generate different rotation angles, and different rotation angles correspond to different sin 2 θ and cos 2 θ, further passed through the Wollaston prism to make the two polarization states have different ratios of light splitting, and after beam combination, two beams with different splitting ratios are formed. When the magneto-optical crystal is a Faraday rotator crystal with its own magnetism, it can form a splitting device with a fixed splitting ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 It is a schematic diagram of the structure of the utility model;

[0017] Figure 2 This is a schematic diagram of another embodiment of the structure of the utility model;

[0018] Explanation of the reference numerals: 100, single-fiber collimator; 110, first beam splitter; 111, first wave plate; 120, magneto-optical crystal; 121, coil; 130, Wollaston prism; 140, second wave plate; 150, third wave plate; 160, second light combiner; 170, dual-fiber collimator. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the utility model for which protection is sought, but merely represents the selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0020] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc., should be understood in a broad sense. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; it may refer to a mechanical connection or an electrical connection; it may refer to a direct connection or an indirect connection through an intermediate medium; it may refer to internal communication between two components. Those skilled in the art will be able to understand the specific meanings of the above terms in this utility model in specific circumstances.

[0022] A spectroscopic device includes a first spectroscopic element 110, a first wave plate 111, a magneto-optical crystal 120, a Wollaston prism 130, a second wave plate 140, a third wave plate 150, and a second light combining element 160 arranged along an optical path; the first spectroscopic element 110 is connected to a single-fiber collimator 100 for inputting light; the first wave plate 111 is arranged on one of the optical paths after the first spectroscopic element 110 splits the light to ensure that the polarization state of the linearly polarized light input into the magneto-optical crystal 120 remains consistent; the second wave plate 140 and the third wave plate 150 are each arranged on one of the output optical paths of the Wollaston prism 130; a coil 121 is provided outside the magneto-optical crystal 120; the optical rotation angles of the first wave plate 111, the second wave plate 140, and the third wave plate 150 are 90 degrees; and the second light combining element 160 is connected to a dual-fiber collimator 170 for receiving output light.

[0023] In one embodiment, the first light splitter and the second light combiner are both displacement plates; in another embodiment, the first light splitter and the second light combiner are both birefringent crystals.

[0024] like Figure 2 As shown, in one embodiment, the magneto-optical crystal 120 is a Faraday rotator crystal with its own magnetism, so its rotation angle for polarized light is constant, and a fixed splitting ratio can be achieved, and its splitting ratio cannot be adjusted; and by replacing rotator crystals with different magnetic forces, a splitting device with different splitting ratios can be prepared.

[0025] Working principle: See Figure 1 , the single fiber collimator 100 emits a beam of polarized light containing two polarization states that are perpendicular to each other, such as Figure 1 As shown in s1; after the input light passes through the first beam splitter 110, it is decomposed into two linearly polarized lights with polarization states perpendicular to each other, as shown in FIG. Figure 1 After further passing through the first wave plate 111, one of the linearly polarized light beams rotates 90° so as to keep the polarization state consistent with the other linearly polarized light beam. The first wave plate 111 is only provided on one of the optical paths after the first beam splitter 110 splits the light. Figure 1 The dotted line position of the first wave plate 111 is for the convenience of understanding its specific position. The dotted line indicates that there is no specific structure here. The polarization states of the two polarized lights after passing through the first wave plate 111 are as follows: Figure 1 As shown in s3, the polarization states of the two are consistent;

[0026] Further, through the magneto-optical crystal 120, a coil 121 is provided outside the magneto-optical crystal 120. The magnitude of the current passing through the coil 121 directly determines the magnetic field strength generated by the coil 121. The difference in magnetic field strength will affect the rotation angle θ of the linearly polarized light. The two beams of light rotated by the magneto-optical crystal 120 contain two polarization states at the same time, such as Figure 1As shown in s4;

[0027] Furthermore, the rotated linearly polarized light is decomposed into sin after passing through the Wollaston prism 130. 2 θ and cos 2 θ, thereby completing the splitting ratio of different proportions. After passing through the Wollaston prism 130, the light is decomposed into four beams, such as Figure 1 As shown in s5 in the figure, the ratio of linearly polarized light of the same polarization state is consistent, and light splitting can be achieved by combining them, for example, Figure 1 In s4, the two beams are half of the original input beam, and are decomposed into four beams after passing through the Wollaston prism 130. The upper beam is decomposed into two polarization states. Assume that sin 2 θ=0.9 and cos 2 θ=0.1, the rotation angle θ is about 5°, then s51=0.9, s52=0.1, correspondingly s53=0.9, s54=0.1, by combining s51 and s53, and combining s52 and s54, a 9:1 splitting ratio of the input light is achieved; the second wave plate 140 and the third wave plate 150 are each arranged on one of the output light paths of the Wollaston prism 130, specifically, the second wave plate 140 is arranged on the light path of s53, and the third wave plate 150 is arranged on the light path of s52, s51 and s53 enter the second light combining component 160 to achieve beam combining, and s52 and s54 enter the second light combining component 160 to achieve beam combining, thereby achieving coupled output with the dual-fiber collimator 170 to achieve a splitting effect; and by using currents of different sizes, the coil 121 generates magnetic fields of different sizes, and magnetic fields of different sizes generate different rotation angles, and different rotation angles correspond to different sin 2 θ and cos 2 θ, further through the Wollaston prism 130, the two polarization states are split with different ratios, and two beams of light with different splitting ratios are formed after beam combination, thereby achieving adjustable splitting.

[0028] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the description and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. A spectrometer, characterized in that: The invention comprises a first light splitting element (110), a first wave plate (111), a magneto-optical crystal (120), a Wollaston prism (130), a second wave plate (140), a third wave plate (150), and a second light combining element (160) arranged along an optical path; the first wave plate (111) is arranged on one of the optical paths after light splitting by the first light splitting element (110) to ensure that the polarization state of the linearly polarized light input into the magneto-optical crystal (120) remains consistent; the second wave plate (140) and the third wave plate (150) are each arranged on one of the output optical paths of the Wollaston prism (130); and a coil (121) is provided outside the magneto-optical crystal (120).

2. A spectrometer, characterized in that: The invention comprises a first light splitting element (110), a first wave plate (111), a magneto-optical crystal (120), a Wollaston prism (130), a second wave plate (140), a third wave plate (150), and a second light combining element (160) arranged along an optical path; the first wave plate (111) is arranged on one of the optical paths after the light is split by the first light splitting element (110) to ensure that the polarization state of the linearly polarized light input into the magneto-optical crystal (120) remains consistent; the second wave plate (140) and the third wave plate (150) are each arranged on one of the output optical paths of the Wollaston prism (130); and the magneto-optical crystal (120) is a Faraday rotatable crystal with its own magnetism.

3. A spectrometer according to claim 1 or 2, characterized in that: The first light splitting element (110) is connected to a single-fiber collimator (100) for inputting light.

4. A spectrometer according to claim 1 or 2, characterized in that: The optical rotation angle of the first wave plate (111) is 90 degrees.

5. A spectrometer according to claim 1 or 2, characterized in that: The optical rotation angles of the second wave plate (140) and the third wave plate (150) are 90 degrees.

6. A spectrometer according to claim 1 or 2, characterized in that: The second light combining component (160) is connected to a dual-fiber collimator (170) for receiving output light.

7. A spectrometer according to claim 1 or 2, characterized in that: The first light splitting component (110) and the second light combining component (160) are both displacement plates.

8. The optical splitter according to claim 1 or 2, characterized in that: The first light splitting element (110) and the second light combining element (160) are both birefringent crystals.

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