Optical electric field measuring device and electric field measuring system

Abstract

The application relates to an optical electric field measuring device and an electric field measuring system. The optical electric field measuring device comprises a laser emission assembly for emitting multiple polarized lights; at least two electric field sensing assemblies, each of which is connected with the laser emission assembly, and is used for outputting light intensity signals according to the input polarized light under the action of a to-be-measured electric field; wherein the frequencies and wavelengths of the polarized lights input by different electric field sensing assemblies are different; and a signal processing assembly connected with each electric field sensing assembly, used for converting the light intensity signals output by each electric field sensing assembly into corresponding electric signals respectively, filtering out common mode quantities of the electric signals and amplifying differential mode quantities of the electric signals through differential amplification processing of the electric signals, obtaining a target voltage signal, and determining the to-be-measured electric field according to the target voltage signal. The optical electric field measuring device has high measuring precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric field measurement, and in particular to an optical electric field measurement device and an electric field measurement system. BACKGROUND

[0002] Electric field is a basic physical quantity representing electromagnetic phenomena in nature, and electric field measurement is a basic research method in many scientific and technical fields. With the development of optical technology, in the field of small and micro measurement in high-voltage application scenarios, optical electric field sensors have gradually become the mainstream choice due to their characteristics of strong electric field, wide frequency band and miniaturization. The optical electric field sensor is a sensor that modulates the measured electric field signal on the laser by using the electro-optic effect of the crystal, and reverses the electric field information by detecting the laser intensity.

[0003] However, the optical electric field sensor in the related art has the problem of low measurement accuracy. SUMMARY

[0004] Therefore, it is necessary to provide an optical electric field measurement device and an electric field measurement system with high measurement accuracy.

[0005] In a first aspect, the present application provides an optical electric field measurement device, which comprises:

[0006] a laser emitting assembly for emitting a plurality of polarized lights;

[0007] at least two electric field sensing assemblies, each of the electric field sensing assemblies being connected with the laser emitting assembly, and each of the electric field sensing assemblies being configured to output an optical intensity signal based on the input polarized light under the action of a measured electric field; wherein the frequencies and wavelengths of the input polarized lights of different electric field sensing assemblies are different;

[0008] a signal processing assembly connected with each of the electric field sensing assemblies, and configured to convert the optical intensity signals output by each of the electric field sensing assemblies into corresponding electric signals respectively, to filter out common mode quantities of the electric signals and amplify differential mode quantities of the electric signals through differential amplification processing of the electric signals, to obtain a target voltage signal, and to determine the measured electric field based on the target voltage signal.

[0009] In one of the embodiments, the laser emitting assembly is configured to emit a first polarized light and a second polarized light, and the frequencies and wavelengths of the first polarized light and the second polarized light are different; and the at least two electric field sensing assemblies comprise:

[0010] a first electric field sensing assembly, an input end of the first electric field sensing assembly being connected with the laser emitting assembly, and the first electric field sensing assembly being configured to receive the first polarized light and output a first optical intensity signal based on the first polarized light under the action of the measured electric field;

[0011] a second electric field sensing component, an input end of the second electric field sensing component being connected with the laser emitting component, the second electric field sensing component being configured to receive the second polarized light and output a second light intensity signal based on the second polarized light under the action of the to-be-measured electric field.

[0012] In one of the embodiments, the signal processing component comprises:

[0013] a photoelectric conversion circuit, connected with the first electric field sensing component and the second electric field sensing component respectively, configured to generate a first electric signal based on the first light intensity signal and generate a second electric signal based on the second light intensity signal;

[0014] a differential amplification circuit, connected with the photoelectric conversion circuit, configured to receive the first electric signal and the second electric signal and perform common-mode rejection and differential amplification processing on the first electric signal and the second electric signal to output a target voltage signal;

[0015] a calculation circuit, connected with the differential amplification circuit, configured to calculate the to-be-measured electric field based on the target voltage signal.

[0016] In one of the embodiments, the photoelectric conversion circuit comprises:

[0017] a first photodiode, connected with the differential amplification circuit, configured to receive the first light intensity signal and generate the first electric signal based on the first light intensity signal;

[0018] a second photodiode, connected with the differential amplification circuit, configured to receive the second light intensity signal and generate the second electric signal based on the second light intensity signal.

[0019] In one of the embodiments, the differential amplification circuit comprises:

[0020] an operational amplifier;

[0021] a first resistor, a first end of the first resistor being connected with the photoelectric conversion circuit, configured to receive the first electric signal, a second end of the first resistor being connected with a negative input end of the operational amplifier;

[0022] a second resistor, a first end of the second resistor being connected with the second end of the first resistor, a second end of the second resistor being connected with an output end of the operational amplifier;

[0023] a third resistor, a first end of the third resistor being connected with the photoelectric conversion circuit, configured to receive the second electric signal, a second end of the third resistor being connected with a positive input end of the operational amplifier;

[0024] A fourth resistor, a first end of the fourth resistor is connected with a second end of the third resistor, and a second end of the fourth resistor is grounded.

[0025] In one of the embodiments, the ratio of the resistance of the second resistor to the resistance of the first resistor is the same as the ratio of the resistance of the fourth resistor to the resistance of the third resistor.

[0026] In one of the embodiments, the electric field sensing assembly comprises:

[0027] a substrate;

[0028] a waveguide structure disposed on one side surface of the substrate, for providing a transmission path for polarized light;

[0029] an electrode structure disposed on one side surface of the substrate and spaced apart from the waveguide structure, for sensing a to-be-measured electric field and affecting the phase of the polarized light in the waveguide structure according to the to-be-measured electric field.

[0030] In one of the embodiments, the waveguide structure comprises: an input Y-shaped optical waveguide, a first modulation arm straight waveguide, a second modulation arm straight waveguide, and an output Y-shaped optical waveguide.

[0031] The input end of the input Y-shaped optical waveguide is configured to receive polarized light and generate a first optical signal and a second optical signal based on the polarized light, and the first optical signal and the second optical signal are input into the first modulation arm straight waveguide and the second modulation arm straight waveguide respectively. In the case of sensing a to-be-measured electric field, the to-be-measured electric field performs phase modulation on the first optical signal and the second optical signal, and the modulated first optical signal and second optical signal enter the output Y-shaped optical waveguide and interfere in the output Y-shaped optical waveguide to form an optical intensity signal.

[0032] In one of the embodiments, the length of the first modulation arm straight waveguide is less than the length of the second modulation arm straight waveguide.

[0033] In a second aspect, the present application provides an electric field measurement system, the system comprising the optical electric field measurement device according to any one of the above embodiments.

[0034] The optical electric field measuring device and the electric field measuring system, comprising a laser emitting assembly, at least two electric field sensing assemblies and a signal processing assembly, the laser emitting assembly is used for emitting multiple polarized lights, the electric field sensing assemblies are connected with the laser emitting assembly, the electric field sensing assemblies are used for outputting light intensity signals according to the input polarized lights under the action of the electric field to be measured, the signal processing assembly is connected with each of the electric field sensing assemblies respectively, and is used for converting the light intensity signals output by each of the electric field sensing assemblies into corresponding electric signals respectively, filtering common mode quantities of the electric signals and amplifying differential mode quantities of the electric signals through differential amplification processing of the electric signals, obtaining a target voltage signal, and determining the electric field to be measured according to the target voltage signal. In the application, because the frequencies and wavelengths of the polarized lights received by different electric field sensing assemblies are different, the phase difference exists between the light intensity signals received by the signal processing assembly and the converted electric signals. In the electric field measurement process, when environmental interference occurs, the environmental interference acts on each electric field sensing assembly simultaneously, forming common mode quantities of the light intensity signals and the converted electric signals. The signal processing assembly can eliminate the influence of environmental factors on the electric field measurement by filtering the common mode quantities of the electric signals and amplifying the differential mode quantities of the electric signals, so that the accurate target voltage signal is obtained, and the accurate electric field measurement is realized. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0036] Figure 1 It is a structural schematic diagram of the optical electric field measuring device in an embodiment;

[0037] Figure 2 It is a structural schematic diagram of the electric field sensing assembly in an embodiment;

[0038] Figure 3 It is a structural schematic diagram of the optical electric field measuring device in another embodiment;

[0039] Figure 4 It is a structural schematic diagram of the electric field sensing assembly in another embodiment;

[0040] Figure 5 It is a structural schematic diagram of the optical electric field measuring device in another embodiment;

[0041] Figure 6 It is a structural schematic diagram of the differential amplification circuit in an embodiment. DETAILED DESCRIPTION

[0042] For the purposes of the present application, a more complete description of which will follow, reference will be made to the accompanying drawings. The embodiments of the present application are illustrated by way of example and thus are not limited by the accompanying drawings. Rather, the sole purpose of the drawings is to provide a conceptual understanding of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0044] It is to be understood that the terms “first”, “second”, and so on used herein can be used to describe various elements in the present application, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element.

[0045] Spatially relative terms, such as “under”, “below”, “lower”, “over”, “upper” and the like, can be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if a device in the figures is turned over, elements described as “below” or “under” other elements or features would then be oriented “above” or “over” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. The device can also be oriented in the other direction, and the spatially relative terms used herein are intended to encompass such additional orientations. It is to be understood that the spatially relative terms used herein, including up, down, front, back, right, left, and the like, are intended to be interpreted as described above.

[0046] It is to be noted that when an element is referred to as being “connected” to another element, it can be directly connected to the other element, or connected to the other element through an intervening element. In addition, “connected” in the following embodiments, if there is a transmission of electrical signals or data between the connected objects, should be understood as “electrically connected”, “communicatively connected” and the like.

[0047] As used herein, the singular forms “a”, “an” and “the” can include plural referents unless the context clearly dictates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes” and / or “including”, or the like, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. Also, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0048] In the conventional optical electric field measurement device, only one electric field sensor is included, the polarized light emitted by the laser is divided into two at the input end of the sensor waveguide, and the light waves produce a phase difference after being subjected to electric field phase modulation in the waveguide arms at the Y output port after interference, and becomes the light intensity. The output light field of the sensor can be expressed by formula (1), and the output light intensity of the output port of the electric field sensor can be expressed by formula (2), and the measured electric field signal can be expressed by formula (3):

[0049]

[0050] wherein, is the light field amplitude, is the light field frequency, is the phase difference produced by the polarized light after passing through the two waveguide arms, is the light intensity of the input polarized light, is the measured electric field amplitude, is the measured electric field frequency.

[0051] Therefore, the phase difference can be expressed by formula (4):

[0052]

[0053] wherein is the electric field modulation phase difference, is the inherent phase difference of the sensor, also known as the linear working point. is the effective refractive index of the waveguide arm 1, is the effective refractive index of the waveguide arm 2, is the inherent arm length difference of the waveguide arm 1 and the waveguide arm 2 in the electric field sensor, is the effective refractive index difference existing between the waveguide arm 1 and the waveguide arm 2 in the electric field sensor.

[0054] Thus, the expression of the light field output by the electric field sensor can be expressed by formula (5), and the output light intensity of the output port of the electric field sensor can be expressed by formula (6):

[0055]

[0056] It can be seen that the output light intensity has a cosine relationship with the wavelength of the input polarized light.

[0057] The optical power output by the electric field sensor can be expressed by formula (7):

[0058]

[0059] wherein, is the optical power of the input polarized light. The sensor works in a linear working region if and only if It is known that the electric field sensor works in a linear working point by tuning the wavelength. When the sensor works in the linear working region, The intrinsic phase difference changes when there is environmental disturbance, so that the phase difference of the electric field sensor deviates from the linear working point.

[0060] When the sensor is in the linear working point and there is environmental disturbance, the optical power outputted by the electric field sensor can be approximately expressed by formula (8):

[0061]

[0062] The effective optical power inputted to the photodiode is:

[0063]

[0064] The photoelectric current outputted by the photodiode is:

[0065]

[0066] It can be seen that the photoelectric current converted by the photodiode contains the phase difference disturbed by the environmental factors and the modulation of the electric field to the refractive index of the crystal . Thus, the size of the measured electric field is inaccurate.

[0067] In an exemplary embodiment, referring to Figure 1 , the present application provides an optical electric field measurement device, which comprises a laser emission assembly 10, at least two electric field sensing assemblies 20 and a signal processing assembly 30.

[0068] The laser emission assembly 10 is used for emitting multiple polarized lights. The electric field sensing assemblies 20 are connected with the laser emission assembly 10, and the electric field sensing assemblies 20 are used for outputting light intensity signals according to the input polarized light under the action of the electric field to be measured; wherein the frequencies and wavelengths of the polarized light inputted to different electric field sensing assemblies 20 are different. The signal processing assembly 30 is connected with each electric field sensing assembly 20 respectively, and is used for converting the light intensity signals outputted by each electric field sensing assembly 20 into corresponding electric signals respectively, filtering out the common mode quantities of the electric signals and amplifying the differential mode quantities of the electric signals by differential amplification processing of the electric signals, obtaining a target voltage signal, and determining the electric field to be measured according to the target voltage signal.

[0069] In the embodiment, the laser emitting assembly 10 can be a tunable laser, which refers to a laser whose output wavelength can be continuously changed within a certain range. For example, the laser emitting assembly 10 can be one of a dye laser, a ruby laser, a color center laser, a tunable excimer laser, and a thulium-doped laser.

[0070] When the electric field needs to be measured, the electric field sensing assembly 20 can be placed in the electric field to be measured, and the polarized light is input to the electric field sensing assembly 20 by the laser emitting assembly 10. Under the action of the electric field to be measured, the phase of the polarized light transmitted in the electric field sensing assembly 20 changes, so that the light intensity signal output by the electric field sensing assembly 20 contains information of the electric field to be measured. Then, the signal processing assembly can convert the light intensity signal output by the electric field sensing assembly into an electric signal, which also contains information of the electric field to be measured, so that the electric field to be measured can be determined through the electric signal. In actual application, various environmental factors such as complex outdoor complex electromagnetic conditions, temperature, humidity, etc. will affect the accuracy of the measurement result of the optical electric field sensor. Even though the light intensity signal output by the electric field sensing assembly 20 contains information of the electric field to be measured and environmental interference factors, and the electric signal converted from the light intensity signal also contains information of the electric field to be measured and environmental interference factors, it is difficult to accurately determine the electric field to be measured.

[0071] The optical electric field measuring device of the present application has a plurality of electric field sensing assemblies 20. In application, the electric field sensing assemblies 20 can be integrated on a crystal plate, so that they have small mutual spacing and do not interfere with each other, ensuring that they have similar environmental electromagnetic field conditions and environmental temperature and humidity conditions when measuring the same electric field to be measured. Then, when there is environmental interference, the environmental interference is converted into a common mode, and the frequency and wavelength of the polarized light received by each electric field sensing assembly 20 are controlled to be different, so that the polarized light input to each electric field sensing assembly 20 has a phase difference, and the light intensity signal output by each electric field sensing assembly 20 and the converted electric signal have a phase difference, forming a differential mode. Then, the signal processing assembly 30 can filter out the common mode and amplify the differential mode, so as to eliminate the influence of environmental factors on electric field measurement and improve the accuracy of electric field measurement.

[0072] The optical electric field measuring device comprises a laser emission assembly, at least two electric field sensing assemblies and a signal processing assembly. The laser emission assembly is configured to emit polarized light. The electric field sensing assemblies are connected to the laser emission assembly. The electric field sensing assemblies are configured to output light intensity signals according to the input polarized light under the action of the electric field to be measured. The signal processing assembly is connected to each of the electric field sensing assemblies. The signal processing assembly is configured to convert the light intensity signals output by each of the electric field sensing assemblies into corresponding electric signals. The signal processing assembly is configured to amplify the differential mode of each of the electric signals by filtering the common mode of each of the electric signals, so as to obtain a target voltage signal. The signal processing assembly is configured to determine the electric field to be measured according to the target voltage signal.

[0073] In one exemplary embodiment, referring to Figure 2 The electric field sensing assembly 20 comprises a substrate 201, a waveguide structure 202 and an electrode structure 203. The waveguide structure 202 is arranged on one side surface of the substrate 201 and is configured to provide a transmission path for the polarized light. The electrode structure 203 is arranged on one side surface of the substrate 201 and is spaced apart from the waveguide structure 202. The electrode structure 203 is configured to sense the electric field to be measured and to affect the phase of the polarized light in the waveguide structure according to the electric field to be measured.

[0074] Specifically, the substrate 201 can be an x-cut lithium niobate crystal. The waveguide structure 202 can comprise an input Y-shaped optical waveguide 2021, a first modulation arm straight waveguide 2022, a second modulation arm straight waveguide 2023 and an output Y-shaped optical waveguide 2024. The electrode structure 203 can comprise two ground electrodes (a first ground electrode and a second ground electrode) and a signal electrode. The signal electrode is located between the first modulation arm straight waveguide 2022 and the second modulation arm straight waveguide 2023. The first ground electrode is located on the side of the first modulation arm straight waveguide 2022 away from the second modulation arm straight waveguide 2023. The second ground electrode is located on the side of the second modulation arm straight waveguide 2023 away from the first modulation arm straight waveguide 2022.

[0075] The input end of the input Y-shaped optical waveguide 2021 is configured to receive polarized light, and generate a first optical signal and a second optical signal based on the polarized light, and input the first optical signal and the second optical signal into the first modulation arm straight waveguide 2022 and the second modulation arm straight waveguide 2023 respectively. The length of the first modulation arm straight waveguide 2022 is less than the length of the second modulation arm straight waveguide 2023. When the electric field to be measured is uniformly distributed between the ground electrode and the signal electrode, the refractive index of the first modulation arm straight waveguide 2022 and the second modulation arm straight waveguide 2023 changes, so that the phase of the first optical signal and the second optical signal transmitted therein changes. The modulated first optical signal and the second optical signal enter the output Y-shaped optical waveguide 2024 and interfere with each other in the output Y-shaped optical waveguide 2024 to form an optical intensity signal.

[0076] In an exemplary embodiment, the laser emission assembly 10 is configured to emit a first polarized light and a second polarized light, the first polarized light and the second polarized light having different frequencies and wavelengths. Figure 3 and Figure 4 The at least two electric field sensing assemblies include a first electric field sensing assembly 21 and a second electric field sensing assembly 22.

[0077] The input end of the first electric field sensing assembly 21 is connected with the laser emission assembly. The first electric field sensing assembly 21 is configured to receive the first polarized light, and output a first optical intensity signal based on the first polarized light under the action of the electric field to be measured. The input end of the second electric field sensing assembly 22 is connected with the laser emission assembly. The second electric field sensing assembly 22 is configured to receive the second polarized light, and output a second optical intensity signal based on the second polarized light under the action of the electric field to be measured.

[0078] In the embodiment, the first electric field sensing component 21 and the second electric field sensing component 22 can share a substrate. In an example, a mask plate capable of preparing two electric field sensing components at the same time is prepared first, and the polarization width of the mask plate is designed to be 6 um. The same polarization pattern is set at a distance of 20 um from the polarization pattern in the y+ direction. Then, the x-cut lithium niobate wafer is cleaned, and photoresist is spin-coated. The pattern on the mask plate is transferred to the photoresist by ultraviolet light exposure. After development, the polarization inversion of the non-photoresist covered area is realized by liquid electrode, and the periodic polarization is completed. Subsequently, a layer of silicon dioxide film is sputtered on the x surface of the lithium niobate wafer, photoresist is spin-coated, and the waveguide pattern is printed on the surface using the mask plate and ultraviolet light exposure. After development, the waveguide pattern is obtained on the surface layer of silicon dioxide. Wet etching is used to etch the exposed silicon dioxide, and the waveguide path is obtained. Subsequently, proton exchange, annealing and polishing processes are performed to obtain the waveguide structure after anti-proton exchange. Finally, the surface metal electrode preparation is completed using vacuum coating combined with photolithography process. The electrode mask plate is designed, and the same polarization pattern is set at a distance of 20 um from the polarization pattern in the y+ direction. A layer of titanium metal electrode with a thickness of 0.3 um is prepared on the surface of the lithium niobate crystal by evaporation. A layer of gold is further evaporated on the titanium, and the total electrode thickness is about 0.8 um. Subsequently, photoetching technology is used, photoresist is spin-coated, and the electrode pattern is printed on the surface using the mask plate. Then, development and etching are performed to obtain the waveguide chip with Au / Ti electrode.

[0079] The first electric field sensing component 21 is used to receive the first polarized light with a frequency of f1 and a wavelength of λ1 emitted by the laser emitting component 10, and the second electric field sensing component 22 is used to receive the second polarized light with a frequency of f2 and a wavelength of λ2 emitted by the laser emitting component 10. By adjusting the wavelength of the polarized light through the laser emitting component 10, the phase difference between the first polarized light and the second polarized light input into the first electric field sensing component 21 and the second electric field sensing component 22 can be . That is, the phase difference between the first polarized light and the second polarized light input into the first electric field sensing component 21 and the second electric field sensing component 22 is , .

[0080] In an exemplary embodiment, referring to Figure 5 , the signal processing component 30 includes a photoelectric conversion circuit 31, a differential amplification circuit 32 and a calculation circuit 33.

[0081] The photoelectric conversion circuit 31 is connected with the first electric field sensing component 21 and the second electric field sensing component 22 respectively, and is used to generate a first electric signal according to the first light intensity signal and a second electric signal according to the second light intensity signal. The differential amplification circuit 32 is connected with the photoelectric conversion circuit 31, and is used to receive the first electric signal and the second electric signal, and to perform common-mode rejection and differential amplification processing on the first electric signal and the second electric signal, and to output a target voltage signal. The calculation circuit 33 is connected with the differential amplification circuit 32, and is used to calculate and determine the to-be-measured electric field according to the target voltage signal.

[0082] Specifically, the photoelectric conversion circuit 31 can include a first photodiode and a second photodiode,

[0083] The first photodiode is connected with the differential amplification circuit 3211, and is configured to receive the first light intensity signal and generate a first electric signal according to the first light intensity signal. The second photodiode is connected with the differential amplification circuit 32, and is configured to receive the second light intensity signal and generate a second electric signal according to the second light intensity signal.

[0084] Since the first polarized light and the second polarized light have a phase difference, the amount of current converted by the first photodiode can be represented by formula (11), and the amount of current converted by the second photodiode can be represented by formula (12):

[0085]

[0086] Since , the above formula (11) and formula (12) can be rewritten as formula (13) and formula (14):

[0087]

[0088] In an embodiment, please continue to refer to Figure 6 , the differential amplification circuit 32 includes an operational amplifier V1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4.

[0089] The first end of the first resistor R1 is connected with the photoelectric conversion circuit 31, and is configured to receive the first electric signal. The second end of the first resistor R1 is connected with the negative input end of the operational amplifier V1. The first end of the second resistor R2 is connected with the second end of the first resistor R1, and the second end of the second resistor R2 is connected with the output end of the operational amplifier V1. The first end of the third resistor R3 is connected with the photoelectric conversion circuit 31, and is configured to receive the second electric signal. The second end of the third resistor R3 is connected with the positive input end of the operational amplifier V1. The first end of the fourth resistor R4 is connected with the second end of the third resistor R3, and the second end of the fourth resistor R4 is grounded.

[0090] Since the first electric field sensing assembly 21 and the second electric field sensing assembly 22 of the present application have the same linear working area, and the phase difference of the first light intensity signal and the second light intensity signal that can be output is , so that the first electric signal output by the first photodiode and the second electric signal output by the second photodiode have The phase difference between the first electric signal and the second electric signal is caused by the change of the phase difference of the laser. The change caused by the environmental factors such as temperature acts on the waveguides of the first electric field sensing assembly 21 and the second electric field sensing assembly 22 simultaneously, and is considered as equivalent in the case of minimal process error, which is a common mode. The wavelength of the laser is artificially modulated so that the first electric signal and the second electric signal have a phase difference. The first electric signal and the second electric signal enter the differential amplification circuit 32, in which the common mode is filtered out and the differential mode is amplified, to obtain the target voltage signal, which only includes the information of the electric field to be measured and does not have the interference of the environment.

[0091] In the embodiment, the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 are resistors with completely matched gain, and the resistance ratio of the second resistor to the first resistor is the same as the resistance ratio of the fourth resistor to the third resistor, that is, The operational amplifier V1 can be an operational amplifier of the LM743 type.

[0092] In one exemplary embodiment, the present application provides an electric field measurement system, which comprises the optical electric field measurement device of any of the above embodiments.

[0093] In the description of the present specification, the description of the terms "some embodiments", "other embodiments", "ideal embodiments", and the like means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0094] The technical features of the above embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present specification.

[0095] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical electric field measuring device, characterized in that, The device includes: Laser emitting components are used to emit light with multiple polarizations; At least two electric field sensing components are provided, each of which is connected to the laser emitting component. The electric field sensing components are used to output a light intensity signal based on the input polarized light under the action of the electric field to be measured. The frequency and wavelength of the polarized light input to different electric field sensing components are different. A signal processing component is connected to each of the electric field sensing components and is used to convert the light intensity signals output by each of the electric field sensing components into corresponding electrical signals. By performing differential amplification processing on each electrical signal, the common mode of each electrical signal is filtered out and the differential mode of each electrical signal is amplified to obtain a target voltage signal, and the electric field to be measured is determined based on the target voltage signal. The electric field sensing component includes: a substrate; a waveguide structure disposed on one side surface of the substrate for providing a transmission path for polarized light; and an electrode structure disposed on one side surface of the substrate and spaced apart from the waveguide structure for sensing the electric field to be measured and influencing the phase of the polarized light in the waveguide structure according to the electric field to be measured. The waveguide structure includes: an input Y-shaped optical waveguide, a first modulation arm straight waveguide, a second modulation arm straight waveguide, and an output Y-shaped optical waveguide; wherein, the input end of the input Y-shaped optical waveguide is used to receive polarized light and generate a first optical signal and a second optical signal based on the polarized light, and the first optical signal and the second optical signal are respectively input into the first modulation arm straight waveguide and the second modulation arm straight waveguide; when a test electric field is sensed, the test electric field modulates the phase of the first optical signal and the second optical signal, and the modulated first optical signal and the second optical signal enter the output Y-shaped optical waveguide and converge and interfere within the output Y-shaped optical waveguide to form an optical intensity signal.

2. The optical electric field measuring device according to claim 1, characterized in that, The laser emitting component is used to emit first polarized light and second polarized light, the first polarized light and the second polarized light having different frequencies and wavelengths; The at least two electric field sensing components include: A first electric field sensing component, the input end of which is connected to the laser emitting component, is used to receive the first polarized light and, under the action of the electric field to be measured, output a first light intensity signal based on the first polarized light. The second electric field sensing component has its input end connected to the laser emitting component. The second electric field sensing component is used to receive the second polarized light and, under the action of the electric field to be measured, outputs a second light intensity signal based on the second polarized light.

3. The optical electric field measuring device according to claim 2, characterized in that, The signal processing component includes: A photoelectric conversion circuit is connected to the first electric field sensing component and the second electric field sensing component respectively, and is used to generate a first electrical signal based on the first light intensity signal and a second electrical signal based on the second light intensity signal. A differential amplifier circuit, connected to the photoelectric conversion circuit, is used to receive the first electrical signal and the second electrical signal, and to perform common-mode rejection and differential amplification on the first electrical signal and the second electrical signal, and output the target voltage signal. A calculation circuit, connected to the differential amplifier circuit, is used to calculate and determine the electric field to be measured based on the target voltage signal.

4. The optical electric field measuring device according to claim 3, characterized in that, The photoelectric conversion circuit includes: A first photodiode is connected to the differential amplifier circuit to receive a first light intensity signal and generate the first electrical signal based on the first light intensity signal. The second photodiode is connected to the differential amplifier circuit and is used to receive the second light intensity signal and generate the second electrical signal based on the second light intensity signal.

5. The optical electric field measuring device according to claim 3, characterized in that, The differential amplifier circuit includes: Operational amplifier; A first resistor, the first end of which is connected to the photoelectric conversion circuit for receiving the first electrical signal, and the second end of which is connected to the negative input terminal of the operational amplifier; The second resistor has a first end connected to the second end of the first resistor, and the second end of the second resistor is connected to the output terminal of the operational amplifier. The third resistor has its first end connected to the photoelectric conversion circuit for receiving the second electrical signal, and its second end connected to the positive input terminal of the operational amplifier. The fourth resistor has its first end connected to the second end of the third resistor, and its second end is grounded.

6. The optical electric field measuring device according to claim 5, characterized in that, The resistance ratio of the second resistor to the first resistor is the same as the resistance ratio of the fourth resistor to the third resistor.

7. The optical electric field measuring device according to claim 1, characterized in that, The length of the first modulation arm straight waveguide is less than the length of the second modulation arm straight waveguide.

8. An electric field measurement system, characterized in that, The system includes the optical electric field measuring device according to any one of claims 1-7.

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