CN110160913A - Liquid densimeter and liquid density measurement system - Google Patents
Liquid densimeter and liquid density measurement system Download PDFInfo
- Publication number
- CN110160913A CN110160913A CN201910551581.0A CN201910551581A CN110160913A CN 110160913 A CN110160913 A CN 110160913A CN 201910551581 A CN201910551581 A CN 201910551581A CN 110160913 A CN110160913 A CN 110160913A
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- liquid
- film
- fpi
- lock pin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 56
- 238000001739 density measurement Methods 0.000 title claims abstract description 6
- 239000013307 optical fiber Substances 0.000 claims abstract description 58
- 239000010408 film Substances 0.000 claims description 40
- 239000010409 thin film Substances 0.000 claims description 17
- 238000005259 measurement Methods 0.000 claims description 11
- 239000003292 glue Substances 0.000 claims description 9
- 239000000835 fiber Substances 0.000 claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 230000002708 enhancing effect Effects 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 238000003466 welding Methods 0.000 claims description 2
- 240000007594 Oryza sativa Species 0.000 claims 1
- 235000007164 Oryza sativa Nutrition 0.000 claims 1
- 239000008199 coating composition Substances 0.000 claims 1
- 235000009566 rice Nutrition 0.000 claims 1
- 230000035945 sensitivity Effects 0.000 abstract description 6
- 239000012530 fluid Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 239000006117 anti-reflective coating Substances 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011173 biocomposite Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/24—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing the transmission of wave or particle radiation through the material
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/26—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by measuring pressure differences
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Measuring Fluid Pressure (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention belongs to the technical field of optical fiber sensing, and particularly relates to a liquid densimeter and a liquid density measurement system. The densimeter comprises a sleeve and two FPI structures fixedly arranged in the sleeve in a cascade mode, wherein the tail end of each FPI structure is provided with an F-P cavity structure which is in contact with liquid to be measured and used for measuring the pressure intensity in the liquid to be measured, and the two FPI structures are located at different heights in the sleeve to measure the liquid pressure intensities at different positions; each FPI structure outputs the measured liquid pressure through the internal optical fiber, one end of the internal optical fiber of each FPI structure is in contact with the F-P cavity structure, and the other end of the internal optical fiber of each FPI structure extends out of the sleeve. The liquid densimeter provided by the invention has the characteristics of small volume, high sensitivity and automatic temperature compensation.
Description
Technical field
The invention belongs to technical field of optical fiber sensing more particularly to a kind of liquid densimeter and liquid density measurement systems.
Background technique
Densitometer is a kind of metrical instrument for measuring fluid density.Currently, it is close to common are electronic type densitometer, static pressure type
Degree meter, vibrating densimeter and radioisotope densimeter etc..But structure is complicated or at high cost for the presence of these densitometers, or
The disadvantages such as measurement accuracy is low.
Densitometer based on optical principle has many advantages, such as that high-precision, structure be simple, electromagnetism interference.Optical profile type at present
Densitometer is all based on the float-type structure of Archimedes'law, i.e. the buoyancy and fluid density that are subject in liquid of object
Directly proportional, the buoyancy that float is subject to passes to fiber grating by mechanical lever, causes the strain of grating, detection grating optical signal
Change can calculate buoyancy size, and then obtain fluid density.
However, the shortcomings that float-type is because having float and mechanical structure, volume does not accomplish very little.Float volume is bigger,
The buoyancy being subject to is also bigger, and sensitivity is just high, but entire densitometer volume is also bigger, so volume and sensitivity can not be simultaneous
?.
Summary of the invention
(1) technical problems to be solved
For existing technical problem, the present invention provides a kind of liquid densimeter based on cascaded optical fiber FPI, has
The advantages of small in size, high sensitivity, temperature self-compensation.
(2) technical solution
The present invention provides a kind of liquid densimeter, and two FPI structures of cascade setting are fixed including casing and in casing,
The end of each FPI structure is provided with the F-P cavity for contacting with testing liquid and being used to measure pressure in the testing liquid
Structure, two FPI structures are located at the different height in described sleeve pipe, to measure the liquid pressure at different location；Each FPI
The liquid pressure of measurement is passed through internal optical fiber output, one end of each FPI inside configuration optical fiber and the F-P cavity by structure
Structure contact, the other end extend described sleeve pipe.
Further, the FPI structure includes:
Optical fiber, lock pin and film；
The film is fixed on the bottom end face of the lock pin, and forms tubular cavity with lock pin；
Casing is extended in one end of the optical fiber, and the other end is inserted into the tubular cavity, and the end of the other end with
It is fixed when the film is apart from preset value d1, end, lock pin and the film of the optical fiber form the F-P cavity structure；
The lock pin is fixed on internal surface of sleeve pipe, and length is less than the length of the optical fiber.
Further, the lock pin is fixed adjustably to internal surface of sleeve pipe by means of limiting steel ring.
Further, the lock pin is circular tube shaped, the axially disposed glue groove and use having for fixing optical fiber of lock pin inner wall
In the air pressure balance slot of air pressure in balance F-P cavity body.
Further, the optical fiber is single mode optical fiber, and the film is single thin film；
Alternatively, the optical fiber is single mode optical fiber, the film is plural layers；
Alternatively, the optical fiber is multimode fibre, the film is single thin film；
Alternatively, the optical fiber is multimode fibre, the film is plural layers.
Further, the plural layers are made of single thin film and the reflection enhancing coating being arranged in above single thin film.
Further, the thickness of the single thin film is 1-30 microns.
Further, in the plural layers, single thin film with a thickness of 1-30 microns, the thickness of the reflection enhancing coating
It is 10-500 nanometers.
Further, the film by glue bond the bottom end face of lock pin or by laser welding in the bottom of lock pin
End face.
The present invention also provides a kind of liquid density measurement system, including as described in above-mentioned either a program liquid densimeter and
The optical fiber for extending casing in spectrometer, the spectrometer and the liquid densimeter is connect.
(3) beneficial effect
Liquid densimeter provided by the invention incudes the variation of grating by two cascade FPI structures, and then is pressed
Strong poor and fluid density, the high sensitivity of measurement and has the characteristics that temperature self-compensation.Due to using optical fiber measurement, the densitometer
Strong antijamming capability, corrosion resistance is high, while the volume very little of optical fiber, and diameter is about 125 microns, therefore entire fluid density
The volume very little of meter.There is no mechanical structure in densitometer, structure is simpler, works more reliable.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of liquid densimeter provided by the invention；
Fig. 2 is the sectional view at the A-A of liquid densimeter provided by the invention.
[description of symbols]
11: the first optical fiber；12: the first lock pins；13: the first film；14: the first F-P cavities；21: the second optical fiber；22: the second
Lock pin；23: the second films；24: the second F-P cavities；5: limit steel ring；61: first sleeve；62: the second casings；7: air pressure balance
Slot；8: glue groove.
Specific embodiment
In order to preferably explain the present invention, in order to understand, with reference to the accompanying drawing, by specific embodiment, to this hair
It is bright to be described in detail.
The present invention provides a kind of liquid densimeter, and the principle is as follows:
Pressure in liquid at page depth h are as follows: P=ρ gh, the then pressure difference of two different liquid level depth are as follows: Δ P
=ρ g (h1-h2), therefore, the pressure difference of two different liquid level depth locations is measured, the close of surveyed liquid can be calculated
Degree:
Based on the above principles, the invention proposes liquid densimeters as shown in Figure 1.The liquid densimeter include casing and
Two FPI structures of fixed cascade setting in casing, the end of each FPI structure is provided with to be contacted simultaneously with testing liquid
For measuring the F-P cavity structure of pressure in the testing liquid, two FPI structures are located at the different height in described sleeve pipe, with
Measure the liquid pressure at different location；The liquid pressure of measurement is passed through internal optical fiber output by each FPI structure, each
One end of a FPI inside configuration optical fiber is contacted with the F-P cavity structure, and the other end extends described sleeve pipe.
Above-mentioned cascade refers to that the identical first FPI structure of two structures and the 2nd FPI structure are disposed in parallel in casing,
Wherein, the first FPI structure includes the first optical fiber 11, the first lock pin 12 and the first film 13, and the first optical fiber 11 is inserted into the first lock pin
In 12, the first film 13 is fixed on the bottom end face of the first lock pin 12, the bottom end face of the first film 13 and the first optical fiber 11 it
Between form the first F-P cavity 14；2nd FPI structure includes the second optical fiber 21, the second lock pin 22 and the second film 23, the second optical fiber 21
It is inserted into the second lock pin 22, the second film 23 is fixed on the bottom end face of the second lock pin 22, the second film 23 and the second optical fiber 21
Bottom end face between form the second F-P cavity 24.
Wherein, optical fiber is made of the covering of fibre core and the encirclement fibre core.
Difference in height Δ h is provided between the first film 13 and the second film 23, difference in height Δ h can be selected arbitrarily.
It is d1 that first F-P cavity 14 is identical with the length of the second F-P cavity 24, and is cavity, is with the first F-P cavity 14
Example, the length of the first F-P cavity 14 refer to the bottom end face of the first optical fiber 11 to the distance of the first film 13.
Wherein, the first optical fiber 11 and the second optical fiber 21 are same fiber material, can select single mode optical fiber or simultaneously simultaneously
Select multimode fibre.
The first film 13 and the second film 23 are single thin film, wherein the single thin film with a thickness of 1-30 microns,
Material is metal foil.Certainly, the material of single thin film also can be selected plastics, rubber or Biocomposite material, the present invention and not limit
It is fixed.
Certainly, the first film 13 and the second film 23 can also select plural layers simultaneously, and the plural layers as exist
The upper surface of single thin film adds one layer by metal or the reflective membrane or Anti-reflective coating of composite material preparation, and reflective membrane or Anti-reflective coating can
To improve the reflectivity of light.Wherein, the single thin film in plural layers with a thickness of 1-30 microns, reflective membrane or Anti-reflective coating
With a thickness of 10-500 nanometers.
Wherein, the first film 13 and the second film 23 are same material, and structural parameters are identical.
Preferably, the first film 13 and the second film 23 in the bottom end face of lock pin or pass through laser by glue bond respectively
It is welded on the bottom end face of lock pin.
Described sleeve pipe includes first sleeve 61 and the second casing 62, and first sleeve 61 and the second casing 62 are set with being vertically connected with
It sets in the outside of the first FPI structure and the 2nd FPI structure, encapsulation can be played the role of, the material of casing is chosen as stainless steel.
First lock pin 12 and the second lock pin 22 are circular tube shaped, as shown in Fig. 2, each lock pin inner wall is all provided with along the vertical direction
It is equipped with air pressure balance slot 7 and glue groove 8, air pressure balance slot 7 is respectively used to balance the gas in the first F-P cavity 14 and the second F-P cavity 24
It presses, glue can be injected in glue groove 8, for fixing the first optical fiber 11 and the second optical fiber 21.
It include limit steel ring 5 in the liquid densimeter, limit steel ring 5 is used for the first lock pin 12 and the second lock pin 22 is adjustable
It saves land and is fixed on the second casing 62.22 vertical direction of the first lock pin 12 and the second lock pin can be changed by adjusting limit steel ring 5
Relative position, and then change Δ h.
The working principle of liquid densimeter of the invention:
Light is interfered in F-P cavity internal reflection, reflected light.Since the length d1 of F-P cavity changes, interference condition also becomes
Change, obtained wavelength will change.It is counter to release d1 according to the wavelength change that the spectrometer measurement being connected with optical fiber obtains
Variation, and then obtain the pressure for causing the liquid of film deformation.The pressure that two optical fiber measure is respectively P1And P2, according to public affairs
FormulaObtain fluid density.
The FPI structure that cascaded optical fiber is used in the present invention, overcomes influence of the temperature for measurement result.In measurement process
In, due to the influence of temperature, the deformation of the first film and the second film, the volume deformation of lock pin may be caused, and then cause
The variation of 24 structure of first F-P cavity 14 and the second F-P cavity and the change of measurement result.But due to being provided with two FPI knots
Structure, changing as caused by temperature can offset in this way, will not influence the pressure difference and fluid density measured, and there is temperature to mend automatically
The characteristics of repaying.
Simultaneously as using optical fiber measurement, high sensitivity, strong antijamming capability, corrosion resistance are good, while the body of optical fiber
Product very little, diameter is about 125 microns, therefore the volume very little of entire liquid densimeter.
The technical principle of the invention is described above in combination with a specific embodiment, these descriptions are intended merely to explain of the invention
Principle shall not be construed in any way as a limitation of the scope of protection of the invention.Based on explaining herein, those skilled in the art
It can associate with other specific embodiments of the invention without creative labor, these modes fall within this hair
Within bright protection scope.
Claims (10)
1. a kind of liquid densimeter, which is characterized in that two FPI structures of cascade setting are fixed including casing and in casing,
The end of each FPI structure is provided with the F-P cavity for contacting with testing liquid and being used to measure pressure in the testing liquid
Structure, two FPI structures are located at the different height in described sleeve pipe, to measure the liquid pressure at different location；Each FPI
The liquid pressure of measurement is passed through internal optical fiber output, one end of each FPI inside configuration optical fiber and the F-P cavity by structure
Structure contact, the other end extend described sleeve pipe.
2. liquid densimeter according to claim 1, which is characterized in that the FPI structure includes:
Optical fiber, lock pin and film；
The film is fixed on the bottom end face of the lock pin, and forms tubular cavity with lock pin；
Casing is extended in one end of the optical fiber, and the other end is inserted into the tubular cavity, and the end of the other end with it is described
It is fixed when film is apart from preset value d1, end, lock pin and the film of the optical fiber form the F-P cavity structure；
The lock pin is fixed on internal surface of sleeve pipe, and length is less than the length of the optical fiber.
3. liquid densimeter according to claim 2, which is characterized in that the lock pin is by means of limiting steel ring adjustably
It is fixed on internal surface of sleeve pipe.
4. liquid densimeter according to claim 2, which is characterized in that the lock pin is circular tube shaped, and lock pin inner wall is along axis
Air pressure balance slot to the glue groove for fixing optical fiber is provided with and for balancing air pressure in F-P cavity body.
5. liquid densimeter according to claim 2, which is characterized in that the optical fiber is single mode optical fiber, and the film is
Single thin film；
Alternatively, the optical fiber is single mode optical fiber, the film is plural layers；
Alternatively, the optical fiber is multimode fibre, the film is single thin film；
Alternatively, the optical fiber is multimode fibre, the film is plural layers.
6. liquid densimeter according to claim 5, which is characterized in that the plural layers are existed by single thin film and setting
Reflection enhancing coating composition above single thin film.
7. liquid densimeter according to claim 5, which is characterized in that the thickness of the single thin film is 1-30 micro-
Rice.
8. liquid densimeter according to claim 6, which is characterized in that in the plural layers, the thickness of single thin film
Degree be 1-30 microns, the reflection enhancing coating with a thickness of 10-500 nanometers.
9. liquid densimeter according to claim 2, which is characterized in that the film is by glue bond in the bottom of lock pin
End face or by laser welding lock pin bottom end face.
10. a kind of liquid density measurement system, which is characterized in that including spectrometer and as claim 1-9 is described in any item
The optical fiber for extending casing in liquid densimeter, the spectrometer and the liquid densimeter is connect.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910551581.0A CN110160913A (en) | 2019-06-24 | 2019-06-24 | Liquid densimeter and liquid density measurement system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910551581.0A CN110160913A (en) | 2019-06-24 | 2019-06-24 | Liquid densimeter and liquid density measurement system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110160913A true CN110160913A (en) | 2019-08-23 |
Family
ID=67626981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910551581.0A Pending CN110160913A (en) | 2019-06-24 | 2019-06-24 | Liquid densimeter and liquid density measurement system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110160913A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111624134A (en) * | 2020-07-03 | 2020-09-04 | 山东省科学院激光研究所 | Density sensor based on optical fiber F-P cavity |
| CN114839111A (en) * | 2022-04-02 | 2022-08-02 | 中国舰船研究设计中心 | Seawater density measuring device and method based on laser ranging technology |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2593184Y (en) * | 2002-12-19 | 2003-12-17 | 武汉市第十一中学 | Liquid density measuring instument |
| CN102080980A (en) * | 2010-12-06 | 2011-06-01 | 沈阳航空航天大学 | Measuring device and method of oil level/ intensity of airplane fuel oil |
| CN102322897A (en) * | 2011-08-27 | 2012-01-18 | 蚌埠迅科自控有限公司 | Intelligent slurry density and liquid level integrative analysis instrument and analysis method |
| CN105606277A (en) * | 2016-02-23 | 2016-05-25 | 成都凯天电子股份有限公司 | Integrated fiber F-P chamber pressure sensor |
| CN106225965A (en) * | 2016-07-04 | 2016-12-14 | 北京航空航天大学 | A kind of micro high sensitivity optical fiber interference type pressure transducer and preparation method thereof |
| CN106949945A (en) * | 2016-12-27 | 2017-07-14 | 天津市欧斯曼科技有限公司 | A kind of device for measuring liquid level |
| CN109443629A (en) * | 2018-10-29 | 2019-03-08 | 西安天舁敏道光电科技有限公司 | A kind of differential pressure fibre-optical probe structure and its differential pressure fibre optical sensor |
| CN210293975U (en) * | 2019-06-24 | 2020-04-10 | 南方科技大学 | Liquid densimeter and liquid density measurement system |
-
2019
- 2019-06-24 CN CN201910551581.0A patent/CN110160913A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2593184Y (en) * | 2002-12-19 | 2003-12-17 | 武汉市第十一中学 | Liquid density measuring instument |
| CN102080980A (en) * | 2010-12-06 | 2011-06-01 | 沈阳航空航天大学 | Measuring device and method of oil level/ intensity of airplane fuel oil |
| CN102322897A (en) * | 2011-08-27 | 2012-01-18 | 蚌埠迅科自控有限公司 | Intelligent slurry density and liquid level integrative analysis instrument and analysis method |
| CN105606277A (en) * | 2016-02-23 | 2016-05-25 | 成都凯天电子股份有限公司 | Integrated fiber F-P chamber pressure sensor |
| CN106225965A (en) * | 2016-07-04 | 2016-12-14 | 北京航空航天大学 | A kind of micro high sensitivity optical fiber interference type pressure transducer and preparation method thereof |
| CN106949945A (en) * | 2016-12-27 | 2017-07-14 | 天津市欧斯曼科技有限公司 | A kind of device for measuring liquid level |
| CN109443629A (en) * | 2018-10-29 | 2019-03-08 | 西安天舁敏道光电科技有限公司 | A kind of differential pressure fibre-optical probe structure and its differential pressure fibre optical sensor |
| CN210293975U (en) * | 2019-06-24 | 2020-04-10 | 南方科技大学 | Liquid densimeter and liquid density measurement system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111624134A (en) * | 2020-07-03 | 2020-09-04 | 山东省科学院激光研究所 | Density sensor based on optical fiber F-P cavity |
| CN114839111A (en) * | 2022-04-02 | 2022-08-02 | 中国舰船研究设计中心 | Seawater density measuring device and method based on laser ranging technology |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4711126A (en) | Sensor for the measurement of the refractive index of a fluid and/or phase boundary between two fluids by means of visible or invisible light | |
| Grebenikova et al. | The universal optical method for condition control of flowing medium | |
| US8578786B2 (en) | Measuring arrangement with an optical sensor | |
| US20090153846A1 (en) | Fluid level indicator | |
| CN106153978B (en) | Flow velocity testing method based on fiber MEMS Fabry-Perot microcavity | |
| CN103557984B (en) | A kind of method for packing of differential pressure pick-up probe and structure | |
| CN103557985A (en) | Differential pressure sensing method and sensor thereof | |
| CN110160913A (en) | Liquid densimeter and liquid density measurement system | |
| CN107703103B (en) | ghSPR sensor for detecting refractive index and detection method | |
| CN112629744A (en) | Atmospheric pressure sensor based on cascade fiber Fabry-Perot interferometer | |
| CN210293974U (en) | Liquid densimeter and liquid density sensor system based on double-side-hole optical fiber | |
| CN214407857U (en) | Optical fiber pressure sensor and pressure detection equipment | |
| CN203551182U (en) | Packaging structure of differential pressure probe | |
| CN108663076B (en) | Inclination angle sensor and preparation method thereof | |
| JPH04215020A (en) | Optical fiber fuel and liquid gage | |
| CN110160912B (en) | Liquid densimeter based on double-side hole optical fiber and preparation method thereof | |
| CN113267206A (en) | Low-cost repeatedly-producible optical fiber non-closed Fabry-Perot sensor | |
| US6795598B1 (en) | Liquid-level sensor having multiple solid optical conductors with surface discontinuities | |
| CN210293975U (en) | Liquid densimeter and liquid density measurement system | |
| CN110017925B (en) | Waveguide pressure sensor based on M-Z structure and detection method | |
| CN114414134B (en) | Optical fiber hydraulic sensor based on PDMS membrane and vernier effect sensitization | |
| CN109631789A (en) | A kind of highly sensitive F-P sensor with temperature self-compensation effect | |
| CN217059861U (en) | Fiber sensor for simultaneously monitoring stress and corrosion rate of steel bar | |
| CN203981244U (en) | A kind of liquid level sensor based on thin core inclined optical fiber grating | |
| CN208654184U (en) | A kind of fibre optical sensor measuring micro-fluidic speed and direction based on TFBG |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |