阅读说明：本技术 静压传感器的制作方法 (Manufacturing method of static pressure sensor ) 是由 汪超 张鹏飞 陈志超 于 2021-07-30 设计创作，主要内容包括：本发明涉及传感器技术领域,公开了一种静压传感器的制作方法,包括如下步骤：提供第一毛细管和光纤,将第一毛细管套设于光纤外；采用UV胶将第一毛细管与光纤同轴固定,并使光纤的第一端伸出第一毛细管的第一端,伸长量为L0；提供内径大小为D1的第二毛细管,将第二毛细管用疏水溶液浸泡,经过烘干处理后,使第二毛细管的内壁附上一层疏水膜；将第二毛细管套设于第一毛细管外；采用UV胶将第二毛细管与第一毛细管同轴固定,并使第二毛细管的第一端伸出光纤的第一端,伸长量为L1。采用本方法制作而成的传感器,在做静态压力测量时,具有较高的灵敏度,并能够通过设计L0、L1和D1之间的关系,来优化传感器的量程和灵敏度。(The invention relates to the technical field of sensors, and discloses a manufacturing method of a static pressure sensor, which comprises the following steps: providing a first capillary tube and an optical fiber, and sleeving the first capillary tube outside the optical fiber; fixing the first capillary tube and the optical fiber coaxially by using UV glue, and enabling the first end of the optical fiber to extend out of the first end of the first capillary tube, wherein the elongation is L0; providing a second capillary tube with the inner diameter of D1, soaking the second capillary tube in a hydrophobic solution, and drying to attach a layer of hydrophobic membrane on the inner wall of the second capillary tube; sleeving the second capillary tube outside the first capillary tube; the second capillary was fixed coaxially with the first capillary using UV glue, and the first end of the second capillary was extended beyond the first end of the fiber by an amount L1. The sensor manufactured by the method has higher sensitivity when static pressure measurement is carried out, and the measuring range and the sensitivity of the sensor can be optimized by designing the relationship among L0, L1 and D1.)

1. A manufacturing method of a static pressure sensor is characterized by comprising the following steps:

s1, providing a first capillary (200) and an optical fiber (100), and sleeving the first capillary (200) outside the optical fiber (100);

s2, fixing the first capillary (200) and the optical fiber (100) coaxially by adopting UV glue (400), and enabling the first end of the optical fiber (100) to extend out of the first end of the first capillary (200), wherein the elongation is L0;

s3, providing a second capillary tube (300) with the inner diameter of D1, soaking the second capillary tube (300) in a hydrophobic solution, and attaching a layer of hydrophobic membrane (310) to the inner wall of the second capillary tube (300) after drying treatment;

s4, sleeving the second capillary tube (300) outside the first capillary tube (200);

s5, fixing the second capillary (300) and the first capillary (200) coaxially by using UV glue (400), and enabling the first end of the second capillary (300) to extend out of the first end of the optical fiber (100) by an elongation L1.

2. The method for manufacturing a static pressure sensor according to claim 1, wherein the step S2 specifically includes the steps of:

s21, coaxially placing the first end of the first capillary (200) and the first end of the optical fiber (100) by adopting a micro-displacement platform;

s22, performing UV glue (400) point coating and ultraviolet curing on the first end of the first capillary (200) and the first end of the optical fiber (100) to enable the first end of the optical fiber (100) to extend out of the first end of the first capillary (200) and the elongation is L0;

s23, coaxially placing the second end of the first capillary (200) and the second end of the optical fiber (100) by adopting a micro-displacement platform;

and S24, performing UV glue (400) point coating and ultraviolet curing on the second end of the first capillary (200) and the second end of the optical fiber (100).

3. The method for manufacturing a static pressure sensor according to claim 2, wherein the step S22 specifically includes: firstly, extending the first end of the optical fiber (100) out of the first end of the first capillary (200), wherein the extension amount is larger than L0, performing UV glue (400) point coating on the extended part of the optical fiber (100) close to the first capillary (200), then retracting the first end of the optical fiber (100) for a certain distance to ensure that the extension amount of the first end of the optical fiber (100) extending out of the first end of the first capillary (200) is L0, and finally performing ultraviolet curing.

4. The method of claim 1, wherein in step S1, after the first capillary (200) and the optical fiber (100) are provided, the first end of the first capillary (200) and the first end of the optical fiber (100) are respectively cut to be flat, such that the end surface of the first end of the first capillary (200) is perpendicular to the axis of the first capillary (200) and the end surface of the first end of the optical fiber (100) is perpendicular to the axis of the optical fiber (100), and then the first capillary (200) is sleeved outside the optical fiber (100).

5. The method of manufacturing a static pressure sensor according to claim 1, wherein in the step S3, after the second capillary (300) is provided, the first end of the second capillary (300) is cut flat so that the end surface of the second end of the second capillary (300) is perpendicular to the axis of the second capillary (300), and then the second capillary (300) is soaked in the hydrophobic solution.

6. The method for manufacturing a static pressure sensor according to claim 1, wherein the step S5 specifically includes the steps of:

s51, coaxially placing the second capillary (300) and the first capillary (200) by using a micro-displacement platform, enabling the first end of the second capillary (300) to extend out of the first end of the optical fiber (100) by an elongation L1, dispensing the UV glue (400) from the second end of the second capillary (300), and carrying out ultraviolet curing when the UV glue (400) is sucked inwards and is close to the first end of the first capillary (200).

7. The method of manufacturing a static pressure sensor according to any one of claims 1 to 6, wherein the end face of the first end of the optical fiber (100) is kept clean in all steps.

8. The method of manufacturing a static pressure sensor according to any one of claims 1 to 6, wherein in step S3, the hydrophobic solution is a non-oily hydrophobic solution.

9. The method of manufacturing a static pressure sensor according to any one of claims 1 to 6, wherein in step S3, the second capillary (300) is dried by mechanical drying or natural drying.

10. The method of manufacturing a static pressure sensor according to claim 9, wherein in step S3, the second capillary (300) is dried in a dust-free environment.

Technical Field

The invention relates to the technical field of sensors, in particular to a manufacturing method of a static pressure sensor.

Background

The liquid pressure sensor is widely applied to the fields of industry, medical treatment, environmental exploration and the like, and the optical fiber FPI pressure sensor is greatly popular because the optical fiber FPI pressure sensor is easy to apply and install, has small volume and can be suitable for limited space and extreme environment. In the prior art, the sensitivity of the optical fiber FPI hydraulic sensor which is used for sensing by means of deformation of an optical fiber structure under the liquid pressure is not high, and the sensitivity of the optical fiber FPI hydraulic sensor can be improved to a certain extent by introducing a sensitivity enhancing structure, but the volume and the structural complexity of a probe of the FPI hydraulic sensor can be increased, so that the optical fiber FPI hydraulic sensor is difficult to process; although the optical fiber FPI hydraulic sensor with the membrane structure has high sensitivity, the ultrathin membrane structure is easy to damage under pressure, so that the service life of the optical fiber FPI hydraulic sensor is short.

Disclosure of Invention

In view of the above technical problems in the prior art, the present invention provides a method for manufacturing a static pressure sensor, which can manufacture a sensor with high sensitivity suitable for static pressure measurement.

The technical scheme adopted by the invention for solving the technical problems is as follows: a manufacturing method of a static pressure sensor comprises the following steps:

s1, providing a first capillary tube and an optical fiber, and sleeving the first capillary tube outside the optical fiber;

s2, fixing the first capillary tube and the optical fiber coaxially by adopting UV glue, and enabling the first end of the optical fiber to extend out of the first end of the first capillary tube, wherein the elongation is L0;

s3, providing a second capillary tube with the inner diameter of D1, soaking the second capillary tube in a hydrophobic solution, and drying to attach a layer of hydrophobic membrane to the inner wall of the second capillary tube;

s4, sleeving the second capillary tube outside the first capillary tube;

s5, fixing the second capillary and the first capillary coaxially by adopting UV glue, and enabling the first end of the second capillary to extend out of the first end of the optical fiber, wherein the elongation is L1.

In the above method for manufacturing a static pressure sensor, the step S2 specifically includes the following steps:

s21, coaxially placing the first end of the first capillary and the first end of the optical fiber by adopting a micro-displacement platform;

s22, performing UV glue point coating and UV curing on the first end of the first capillary and the first end of the optical fiber to enable the first end of the optical fiber to extend out of the first end of the first capillary, wherein the elongation is L0;

s23, coaxially placing the second end of the first capillary and the second end of the optical fiber by adopting a micro-displacement platform;

and S24, performing UV glue point coating and ultraviolet curing on the second end of the first capillary and the second end of the optical fiber.

In the above method for manufacturing a static pressure sensor, the step S22 specifically includes: firstly, extending the first end of the optical fiber out of the first end of the first capillary, wherein the extension amount is larger than L0, performing UV glue point coating on the extended part of the optical fiber close to the first capillary, then retracting the first end of the optical fiber for a certain distance, enabling the extension amount of the first end of the optical fiber extending out of the first end of the first capillary to be L0, and finally performing ultraviolet curing.

In the above manufacturing method of the static pressure sensor, in the step S1, after the first capillary and the optical fiber are provided, the first end of the first capillary and the first end of the optical fiber are respectively cut flat, so that the end surface of the first end of the first capillary is perpendicular to the axis of the first capillary, and the end surface of the first end of the optical fiber is perpendicular to the axis of the optical fiber, and then the first capillary is sleeved outside the optical fiber.

In the above method for manufacturing the static pressure sensor, in step S3, after the second capillary is provided, the first end of the second capillary is cut flat so that the end surface of the second end of the second capillary is perpendicular to the axis of the second capillary, and then the second capillary is soaked in the hydrophobic solution.

In the above method for manufacturing a static pressure sensor, the step S5 specifically includes the following steps:

s51, coaxially placing the second capillary and the first capillary by using a micro-displacement platform, extending the first end of the second capillary out of the first end of the optical fiber by an elongation L1, performing UV glue spot coating from the second end of the second capillary, and performing ultraviolet curing when the UV glue is sucked inwards and is close to the first end of the first capillary.

In the above method for manufacturing a static pressure sensor, the end face of the first end of the optical fiber is kept clean in all steps.

In the above method for manufacturing a static pressure sensor, in step S3, the hydrophobic solution is a non-oily hydrophobic solution.

In the manufacturing method of the static pressure sensor, in step S3, the second capillary is dried by mechanical drying or natural drying.

In the above method for manufacturing the static pressure sensor, in step S3, the second capillary is dried in a dust-free environment.

The manufacturing method of the static pressure sensor at least has the following beneficial effects: the sensor manufactured by the method has a simple structure, when in manufacturing, the first capillary tube is firstly adopted to fix the optical fiber in advance so as to avoid the optical fiber with a softer structure from drooping, when the second capillary tube is fixedly installed subsequently, the coaxiality among the optical fiber, the first capillary tube and the second capillary tube can be improved, after the sensor is manufactured, the sum of L0 and L1 is used as the total length of an air cavity of the sensor, when in static pressure measurement, the sensor is placed in liquid, the end surface of the first end of the optical fiber and an air-liquid interface are used as a reflecting surface to form an FP interferometer, even if the pressure of the liquid is slightly changed, the height of the liquid entering the air cavity of the sensor can be changed, so that the change of the optical path in the sensor is caused, the change of the optical path in the sensor can be measured and identified by the sensor, the sensor has higher sensitivity, and the relation among L0, L1 and D1 can be designed, the range and the sensitivity of the sensor are optimized, the sensor can be normally used for measurement even under the condition that the pressure of liquid is greatly changed, the sensor cannot be damaged, and the service life of the sensor is prolonged.

Drawings

The invention will be further described with reference to the following figures and examples, in which:

FIG. 1 is a schematic view of a manufacturing process according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a sensor according to an embodiment of the present invention;

fig. 3 is a graph showing the relationship between the liquid pressures P and Lx in the example of the present invention.

In the drawings: 100 fibers, 200 first capillaries, 300 second capillaries, 310 hydrophobic films, 400UV glue, 500 liquid.

Detailed Description

Referring to fig. 1, an embodiment of the present invention provides a method of fabricating a static pressure sensor, including the steps of:

s1, providing a first capillary 200 and the optical fiber 100, and sleeving the first capillary 200 outside the optical fiber 100;

s2, fixing the first capillary 200 and the optical fiber 100 coaxially by using UV glue 400, and extending the first end of the optical fiber 100 out of the first end of the first capillary 200 by an extension amount L0;

s3, providing a second capillary tube 300 with the inner diameter of D1, soaking the second capillary tube 300 in a hydrophobic solution, and drying to attach a layer of hydrophobic membrane 310 on the inner wall of the second capillary tube 300;

s4, sleeving the second capillary tube 300 outside the first capillary tube 200;

s5, fixing the second capillary 300 and the first capillary 200 coaxially with the UV glue 400, and extending the first end of the second capillary 300 out of the first end of the optical fiber 100 by an amount of L1.

The sensor manufactured by the method has a simple structure, when in manufacturing, the optical fiber 100 is fixed in advance by the first capillary 200 to avoid the optical fiber 100 with a soft structure from drooping, the coaxiality among the optical fiber 100, the first capillary 200 and the second capillary 300 can be improved when the second capillary 300 is fixedly installed subsequently, after the sensor is manufactured, the sum of L0 and L1 is used as the total length of an air cavity of the sensor, when in static pressure measurement, the sensor is placed in the liquid 500, the end surface of the first end of the optical fiber 100 and an air-liquid interface are used as reflecting surfaces to form an FP interferometer, and even if the pressure of the liquid 500 is slightly changed, the height of the liquid 500 entering the air cavity of the sensor can be changed, so that the change of the optical path in the sensor can be caused, the sensor can measure and identify, the sensor has high sensitivity, and the L0 and the second capillary 300 can be designed, The relationship between L1 and D1 is used for optimizing the measuring range and the sensitivity of the sensor, so that the sensor can be normally used for measurement even under the condition that the pressure of the liquid 500 is greatly changed, the sensor cannot be damaged, and the service life of the sensor is prolonged. It should be noted that, in the embodiment of the present invention, the first ends are both right ends in fig. 1, and the second ends are both left ends in fig. 1.

Specifically, referring to fig. 2, assuming that the inner diameter of the second capillary 300 is D1 and the outer diameter of the optical fiber 100 is D2, when static pressure measurement is performed, the liquid 500 will enter the air cavity of the sensor, and assuming that the minimum distance from the end face of the first end of the optical fiber 100 to the liquid surface is Lx, the ideal gas state equation "PV ═ nRT" and the volume equation "V ═ pi D" of the cylinder are used²L/4', one can obtain:

wherein A ═ P₀D₀ ²L₀+P₀D₁ ²L₁，P₀For initial pressure, L0 is the length of the expanded air cavity, D0 is the relative inside diameter of the expanded air cavity, and D0²＝D1²-D2²When the values of D1, D2, L0 and L1 are known, the minimum value and the maximum value of the pressure P which can be borne by the sensor can be obtained, and therefore the measuring range of the sensing structure is obtained; from the original formula "FSR ═ λ" of the free spectral range FSR²And/2 nL ", corresponding to the structure of the sensor in the embodiment of the invention, obtaining:

according to the measured FSR value, the actual value of Lx is calculated through the formula, the corresponding pressure P is corresponded, the sensitivity of the sensor is deduced, and the required measuring range and sensitivity can be adjusted by adjusting the numerical values and the interrelation of L0, L1 and D1 according to the requirement. In the examples of the present invention, specific values are provided for illustration:

specifically, the inner diameter D1 of the second capillary 300 is 900 μm, the outer diameter D2 of the optical fiber 100 is 125 μm, the FSR is in the range of about 1580nm, and when the L0 is 332 μm, the L1 is 498 μm, the L0 is 249 μm, and the L1 is 581 μm, the relationship between the pressure P of the liquid 500 and the Lx is as shown in fig. 3, the sensitivity of the sensor can be obtained according to the slope of the fitting line of the P and the Lx in the use process of the obtained sensor, in two cases in fig. 3, it can be seen that the sensitivity of the sensor is different when the values of L0 and L1 are different, and in practical application, the values of L0 and L1 can be designed according to the required range and sensitivity. Further, in this embodiment, the inner diameter of the first capillary 200 is 200 μm and the length is 2cm, and the inner diameter of the first capillary 200 is similar to the outer diameter of the optical fiber 100, so as to fix the optical fiber 100 in advance.

Further, step S2 specifically includes the following steps:

s21, coaxially placing the first end of the first capillary 200 and the first end of the optical fiber 100 by adopting a micro-displacement platform;

s22, performing UV glue 400 spot coating and UV curing on the first end of the first capillary 200 and the first end of the optical fiber 100, so that the first end of the optical fiber 100 extends out of the first end of the first capillary 200, and the elongation is L0;

s23, coaxially placing the second end of the first capillary 200 and the second end of the optical fiber 100 by adopting a micro-displacement platform;

s24, dispensing UV glue 400 and UV curing at the second end of the first capillary 200 and the second end of the optical fiber 100.

In step S22, the UV glue 400 is applied and UV-cured on the first end of the first capillary 200 and the first end of the optical fiber 100, so that the coaxiality between the first end of the first capillary 200 and the first end of the optical fiber 100 can be ensured as much as possible, and when the UV glue 400 is applied and UV-cured on the second end of the first capillary 200 and the second end of the optical fiber 100 in step S24, the first end of the first capillary 200 and the first end of the optical fiber 100 are fixed without being affected by the space between the second end of the first capillary 200 and the second end of the optical fiber 100, so that the size of the L0 is not greatly varied, and the optical fiber 100 having a soft structure can be prevented from sagging even when both ends of the optical fiber 100 are fixed to the first capillary 200.

Further, step S22 specifically includes: firstly, extending the first end of the optical fiber 100 out of the first end of the first capillary 200, wherein the extension amount is larger than L0, performing UV glue 400 spot coating on the extended part of the optical fiber 100 close to the first capillary 200, then retracting the first end of the optical fiber 100 for a certain distance, so that the extension amount of the first end of the optical fiber 100 out of the first end of the first capillary 200 is L0, and finally performing ultraviolet curing. This way, it can be avoided that the UV glue 400 overflows the end surface of the first end of the first capillary 200 when dispensing the UV glue 400, thereby affecting the length of the L0 and even the sensitivity and the range of the sensor. Specifically, when the UV paste 400 is dispensed, the amount of the UV paste 400 applied is enough to fix the optical fiber 100 and the first capillary 200, so that the excessive amount of the UV paste 400 applied can be prevented from causing the paste overflow.

Specifically, in step S1, after providing the first capillary 200 and the optical fiber 100, the first end of the first capillary 200 and the first end of the optical fiber 100 are respectively cut flat such that the end surface of the first end of the first capillary 200 is perpendicular to the axis of the first capillary 200 and the end surface of the first end of the optical fiber 100 is perpendicular to the axis of the optical fiber 100, and then the first capillary 200 is sleeved outside the optical fiber 100. In step S3, after the second capillary 300 is provided, the first end of the second capillary 300 is cut flat so that the end surface of the second end of the second capillary 300 is perpendicular to the axis of the second capillary 300, and the second capillary 300 is soaked in the hydrophobic solution. So as to ensure the accuracy of L0 and L1 and ensure the sensitivity and measuring range of the sensor to be actually required.

Further, step S5 specifically includes the following steps:

s51, placing the second capillary 300 and the first capillary 200 coaxially by using a micro-displacement platform, extending the first end of the second capillary 300 out of the first end of the optical fiber 100 by an elongation amount of L1, dispensing the UV glue 400 from the second end of the second capillary 300, and performing ultraviolet curing when the UV glue 400 is sucked inward and approaches the first end of the first capillary 200. The UV glue 400 is dispensed from the second end of the second capillary 300, the UV glue 400 is sucked inwards under the capillary phenomenon, the speed is reduced, and the UV glue 400 can be prevented from overflowing from the first end of the first capillary 200 while the second capillary 300 can be effectively fixed.

Specifically, the end face of the first end of the optical fiber 100 is kept clean in all steps so as not to affect the measurement effect of the sensor. Specifically, in step S3, the hydrophobic solution is a non-oily hydrophobic solution. Specifically, in step S3, the second capillary 300 is dried by mechanical drying or natural drying for 12 hours or more, and the second capillary 300 is dried in a dust-free environment.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.