CN116481431A - Micro-movement early-warning liquid crystal sensor and preparation method and application thereof - Google Patents
Micro-movement early-warning liquid crystal sensor and preparation method and application thereof Download PDFInfo
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P13/00—Indicating or recording presence, absence, or direction, of movement
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Liquid Crystal (AREA)
Abstract
The invention discloses a micro-movement early-warning liquid crystal sensor and a preparation method and application thereof, wherein the sensor comprises an upper glass substrate and a lower glass substrate which are oppositely arranged, groove arrays which are mutually vertical are arranged on the opposite inner surfaces of the upper glass substrate and the lower glass substrate, a liquid crystal interlayer is arranged between the upper glass substrate and the lower glass substrate, and the liquid crystal interlayer is sealed through a sealing layer; an upper polaroid is arranged on the upper surface of the upper glass substrate, a lower polaroid is arranged on the lower surface of the lower glass substrate, and a backlight plate is arranged below the lower polaroid; the invention utilizes the surface anchoring effect of the liquid crystal to realize micro-movement early warning and monitoring of the measured object, can monitor the micro-movement of the object through the orientation change degree of the liquid crystal molecules, further realizes the early warning purpose, and the sensor has excellent sensitivity, accuracy and durability and can perform real-time early warning and monitoring.
Description
Technical Field
The invention relates to the technical field of sensors, in particular to a micro-movement early-warning liquid crystal sensor, and a preparation method and application thereof.
Background
With the continuous and deep development of intelligence, the sensor plays an important role as an important component of the development of modern technology. Sensor technology has also evolved from structural sensors, solid state sensors, to smart sensors. The intelligent sensor has certain detection, self-diagnosis, data processing and self-adaptation capacity to external information, and is a product of combining microcomputer technology and detection technology. However, from the aspect of industry product structures, the traditional sensor still occupies a larger market proportion, and the sensor material has the defects of low sensitivity, single function and the like, and particularly, the monitoring of early warning information is mostly finished manually, the monitoring is inconvenient, the sensing structure is complex, and the real-time early warning monitoring with high sensitivity is difficult to finish. The novel sensor is obviously insufficient, and the digitalized, intelligent and miniaturized products are seriously insufficient.
Liquid crystals are organic compounds which have both solid crystalline optical properties and liquid flow properties, especially nematic liquid crystals, between solid and liquid states. Since each molecule of the nematic liquid crystal is easy to move freely along the long axis direction, the viscosity of the nematic liquid crystal is low and the nematic liquid crystal is rich in fluidity, the alignment and the movement of the nematic liquid crystal molecules are relatively free and relatively sensitive to external effects, and the liquid crystal can generate different anchoring types according to different directions of externally applied acting forces. At present, a liquid crystal sensor under corresponding working conditions can be prepared by using the characteristic of liquid crystal, for example, chinese patent No. 109696438A discloses a microfluidic array liquid crystal sensor, and real-time observation and recording of the reaction process of a fixed point area can be realized by introducing liquid to be detected under the condition that the liquid crystal is fixed instead of suspended and movable, but the current liquid crystal sensor cannot realize monitoring of micro-movement of an object.
Disclosure of Invention
Aiming at the problems existing in the prior art, the invention provides a micro-movement early-warning liquid crystal sensor, a preparation method and application thereof, which utilize the surface anchoring effect of liquid crystal to realize micro-movement early-warning monitoring of a detected object, and can monitor the micro-movement of the object through the orientation change degree of liquid crystal molecules so as to realize the purpose of early warning.
The technical scheme of the invention is as follows:
in a first aspect of the present invention, a micro-movement early-warning liquid crystal sensor is provided, which comprises an upper glass substrate and a lower glass substrate which are oppositely arranged, wherein groove arrays which are mutually perpendicular are arranged on the opposite inner surfaces of the upper glass substrate and the lower glass substrate, a liquid crystal interlayer is arranged between the upper glass substrate and the lower glass substrate, and the liquid crystal interlayer is sealed by a sealing layer; the upper surface of the upper glass substrate is provided with an upper polaroid, the lower surface of the lower glass substrate is provided with a lower polaroid, and a backlight plate is arranged below the lower polaroid.
In some embodiments of the present invention, the lower surface of the upper glass substrate and the upper surface of the lower glass substrate are covered with an alignment film, and the alignment direction of the alignment film is consistent with the direction of the grooves on the adjacent substrates.
In some embodiments of the present invention, the upper glass substrate has a display function, and the display area is built-in or externally connected with an early warning and monitoring module.
In some embodiments of the invention, the surface groove array has a side length of 50-300 μm, the adjacent arrays are spaced apart by 20-50 μm, and the boundary array is 2-5mm from the edge of the substrate.
In some embodiments of the invention, the thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer comprises thermotropic liquid crystal and lyotropic liquid crystal.
In some embodiments of the present invention, silica beads having a diameter corresponding to the thickness of the liquid crystal interlayer are fixed between the upper glass substrate and the lower glass substrate.
In a second aspect of the present invention, a method for manufacturing a micro-movement early-warning liquid crystal sensor is provided, comprising the steps of:
diamond particles with the same diameter are fixed on the film, and the glass substrate is pressed at constant pressure and speed to rub back and forth on the film for a plurality of times, so that a regular surface groove array is obtained; or, covering a layer of film with induced liquid crystal orientation on the surface of the substrate, and then carrying out surface treatment;
the processed surfaces of the two glass substrates are placed oppositely, the two glass substrates are sealed through a sealing layer, and a liquid crystal injection opening is reserved;
injecting liquid crystal into the interlayer by capillary effect, and standing for 5-10 min to fill the whole interlayer with liquid crystal;
and installing an early warning and monitoring module, a polaroid and a backlight plate.
In some embodiments of the invention, the diamond particles have a diameter of 10-100 μm and a pressure of 1-5N/cm 2 The friction speed is 1-5cm/s, and the friction times are 5-20 times.
In a third aspect of the present invention, a method for using a micro-movement early-warning liquid crystal sensor is provided, in which the sensor is installed at a position where an object moves relatively, and as the object to be monitored moves slightly, upper and lower substrates of the sensor move in a staggered manner in a parallel direction to cause different orientations of liquid crystals, brightness and color changes are observed through a polarizer, monitoring signals of the object to be measured are fed back, the brightness and color change degree depends on the anchoring type of liquid crystal molecules and the magnitude of sequence parameters, and as the moving distance of the object to be monitored increases, the brightness and color changes are more obvious.
In some embodiments of the present invention, the early warning module converts an optical signal into an electrical signal for accurate early warning and monitoring, and specifically includes: initializing an early warning module, monitoring the moving value of the object in real time, judging whether the moving value exceeds the early warning value, if so, carrying out early warning, resetting after early warning, and if not, continuing to carry out real-time monitoring.
One or more of the technical schemes of the invention has the following beneficial effects:
the micro-movement early-warning liquid crystal sensor provided by the invention realizes micro-movement early-warning monitoring of the detected object by utilizing the surface anchoring effect of the liquid crystal, can monitor the micro-movement of the object through the orientation change degree of the liquid crystal molecules, further realizes the early-warning purpose, has excellent sensitivity, accuracy and durability, and can perform real-time early-warning monitoring.
According to the micro-movement early-warning liquid crystal sensor provided by the invention, the surface of the substrate is covered with the thin film with the function of inducing the liquid crystal orientation, so that the early-warning monitoring precision is further improved, the efficient and direct feedback of micro-movement of an object to be detected is realized, the early warning is accurate and sensitive, and the defects of single function, low sensitivity and the like of the sensor in the prior art are overcome. Meanwhile, the sensor is simple in preparation method, controllable in size, free of professional operation and easy to implement.
According to the preparation method of the micro-movement early-warning liquid crystal sensor, the particle size of diamond particles can be adjusted according to the monitoring precision requirement, so that different light transmittance and proper size of liquid crystal arrangement can be obtained, and the application range of the prepared sensor is enlarged.
In the use method of the micro-movement early-warning liquid crystal sensor provided by the invention, two modes of rough early-warning monitoring and accurate early-warning monitoring are provided, and the micro-movement of an object to be monitored can be rapidly detected according to different requirements.
Drawings
Fig. 1 is a schematic diagram of a groove array on a surface of a glass substrate according to the present invention, wherein fig. 1 (a) is a schematic diagram of a groove array on a lower glass substrate, and fig. 1 (b) is a schematic diagram of a groove array on an upper glass substrate.
Fig. 2 is a schematic diagram of the type of anchoring of the liquid crystal surface: among them, fig. 2 (a) shows random plane anchoring, fig. 2 (b) shows uniform plane anchoring, fig. 2 (c) shows vertical anchoring, and fig. 2 (d) shows oblique anchoring.
FIG. 3 shows the alignment state of liquid crystal molecules of the micro-movement early-warning liquid crystal sensor before monitoring;
FIG. 4 is a schematic diagram showing the orientation of liquid crystal molecules under the action of anchoring in the monitoring process of the micro-movement early-warning liquid crystal sensor;
fig. 5 is a schematic diagram of twisting of liquid crystal molecules, wherein fig. 5 (a) is a plan view of the liquid crystal molecules when they are twisted, and fig. 5 (b) is a side view of the liquid crystal molecules when they are twisted.
FIG. 6 is a flow chart of the early warning method of the present invention.
In the figure: 1. an upper polarizing plate; 2. a top glass substrate; 3. an upper alignment film; 4. liquid crystal molecules; 5. a sealing layer; 6. a lower alignment film; 7. a lower glass substrate; 8. a lower polarizing plate; 9. and a backlight plate.
Detailed Description
Term interpretation: anchoring action of liquid crystal surface: i.e. the alignment properties of the liquid crystal molecules at the surface. Liquid crystal molecules near the surface of different morphologies have different orientations due to the surface anchoring effect. Based on the alignment relationship between the molecular orientation and the surface, as shown in fig. 2, the surface anchoring can be divided into four types, i.e., uniform plane anchoring, vertical anchoring, random plane anchoring, and oblique anchoring, and the order parameters characterize the order degree of the liquid crystal molecular alignment.
The invention will be further described with reference to the drawings and examples.
Example 1
In a typical embodiment of the present invention, as shown in fig. 1 and 3, a micro-movement early-warning liquid crystal sensor is provided, which comprises an upper glass substrate 2 and a lower glass substrate 7 which are oppositely arranged, wherein the two glass substrates have good light transmittance, mutually perpendicular groove arrays are arranged on the opposite inner surfaces of the upper glass substrate 2 and the lower glass substrate 7, a liquid crystal interlayer is arranged between the upper glass substrate 2 and the lower glass substrate 7, and the liquid crystal interlayer is sealed by a sealing layer 5; the upper surface of the upper glass substrate 2 is provided with an upper polaroid 1, the polarization direction of the upper polaroid is consistent with the direction of a groove on the upper glass substrate, the lower surface of the lower glass substrate 7 is provided with a lower polaroid 8, the polarization direction of the lower polaroid is consistent with the direction of the groove on the lower glass substrate, namely, the polarization directions of the upper polaroid and the lower polaroid are vertical, and a backlight plate 9 is arranged below the lower polaroid 8, wherein the backlight plate is a light source device and provides a required light source; the polarizer converts natural light into polarized light, and controls whether the light passes through by an optical rotation effect of the liquid crystal layer.
In order to further improve the early warning precision, the lower surface of the upper glass substrate 2 and the upper surface of the lower glass substrate 7 are both covered with an alignment film, specifically, the lower surface of the upper glass substrate is covered with an upper alignment film 3, and the upper surface of the lower glass substrate is covered with a lower alignment film 6, wherein the alignment direction of the alignment film is consistent with the direction of the grooves on the adjacent substrates.
Furthermore, the upper glass substrate has a display function, the display area is internally provided with an early warning and monitoring module, in the embodiment, the early warning and monitoring module can be packaged together with the sensor by using an integrated chip (such as a micro-electromechanical system commonly used in the sensor), the technology of the integrated chip is mature, and the integrated chip is internally and externally connected, so that the early warning and monitoring module can be selected by a person skilled in the art according to the needs.
Further, the side length of the surface groove array is 50-300 mu m, the interval between adjacent arrays is 20-50 mu m, the distance between the boundary arrays and the edge of the substrate is 2-5mm, through the arrangement, on one hand, the fault tolerance can be increased, the error is reduced, on the other hand, the effect of surface textures on anchoring liquid crystal can be enhanced, the anchoring effect of too few/many textures is prevented, and meanwhile, when the silica beads are arranged between the upper glass substrate and the lower glass substrate, fixed positions can be reserved for the silica beads.
Further, the thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer comprises thermotropic liquid crystal and lyotropic liquid crystal, such as 5CB liquid crystal (4-cyano-4 '-amyl biphenyl), 8CB liquid crystal (4' -n-octyl-4-cyano biphenyl), E7 liquid crystal and the like. Thermotropic and lyotropic liquid crystals are injected into the interlayer via the reserved openings by capillary action in the isotropic state and nematic phase, respectively.
Further, the sealing layer is made of flexible and elastic materials, such as PDMS, mylar polyester film and the like, and can deform under force and recover when no external force acts.
In order to ensure that the liquid crystal interlayer has a regular thickness, silica beads with corresponding diameters are fixed between the upper glass substrate and the lower glass substrate, and the change of the distance between the upper substrate and the lower substrate in the deformation process of the sensor is prevented.
In the specific implementation process, the size of the glass substrate is adjusted according to the moving distance of the object to be detected, and similarly, the substrate material can be replaced by other materials with good light transmission according to actual conditions, and surface treatment is performed to a certain extent.
The working principle of the micro-movement early-warning liquid crystal sensor provided by the embodiment is as follows:
when the liquid crystal sensor is used for monitoring the micro-movement of an object, the liquid crystal layer with consistent (or inconsistent) initial molecular arrangement direction moves along with the movement of the object to be measured, different anchoring effects are generated due to different textures of the surface of the glass substrate, namely, the orientation degree of liquid crystal molecules is changed, the light transmittance of liquid crystal is changed along with the change, the brightness and color change can be observed through the polarizing device, and the monitoring signal of the object to be measured is fed back. The brightness and color change degree depends on the anchoring type of the liquid crystal molecules and the magnitude of sequence parameters, and the brightness and color change are more obvious as the moving distance of the object to be measured is larger. The principle is that the groove arrays on the two substrates are mutually perpendicular, and liquid crystal molecules close to the surfaces of the substrates are arranged along the directions of the surface grooves. The liquid crystal molecules located between the two substrates are forced into a twisted state due to the inherent viscosity of the liquid crystal itself. The state of the liquid crystal molecules is twisted, and light is also twisted as it passes through the liquid crystal molecules. When the liquid crystal molecules are subjected to external force, interaction force is generated between the liquid crystal molecules, so that the liquid crystal molecules are rearranged. After the light in this state passes through the lower polarizer, the polarized light is no longer twisted by the liquid crystal molecules. However, the polarizer allows only a light component of a certain fixed direction to pass therethrough, and the polarization direction of the upper polarizer is perpendicular to that of the lower polarizer, so that light cannot pass therethrough. When the moving degree (or times) of the object is different, the rearrangement degree of the liquid crystal molecules is also different, so that the deflection degree of the light is controlled to obtain the brightness and color difference, and the aim of early warning and monitoring is fulfilled. The backlight manufacturing and the liquid crystal display technology are widely used, and therefore, the description is omitted.
Example 2
In an exemplary embodiment of the present invention, a method for preparing a micro-movement early-warning liquid crystal sensor is provided, which includes the following steps:
diamond particles with the same diameter are fixed on the film, and the glass substrate is pressed at constant pressure and speed to rub back and forth on the film for a plurality of times, so that a regular surface groove array is obtained;
in order to further improve the early warning and monitoring precision, a layer of film with induced liquid crystal orientation can be covered on the surface of the substrate, and then surface treatment is carried out;
the treated surfaces of the two glass substrates are placed oppositely, and the two glass substrates are sealed through a sealing layer;
injecting liquid crystal into the interlayer by capillary effect, and standing for 5-10 min to fill the whole interlayer with liquid crystal;
and installing an early warning and monitoring module, a polaroid and a backlight plate.
Specifically, the diameter of the diamond particles is 10-100 μm, and the pressure is 1-5N/cm 2 The friction speed is 1-5cm/s, and the friction times are 5-20 times. Before and after the treatment, the glass substrate is required to be chemically cleaned and ultrasonically cleaned, and then dried by nitrogen gas to remove residual particles, wherein the chemical cleaning can be selected from acetone, ethanol, deionized water and the like.
In some embodiments of the present example, the particle size of the diamond particles may be adjusted according to the accuracy of the monitoring to obtain different light transmittance and proper size of the liquid crystal alignment.
Example 3
In a typical implementation mode of the invention, a use method of a micro-movement early-warning liquid crystal sensor is provided, the sensor is arranged at a position where relative movement of an object occurs, the sensor deforms when the object relatively moves, the upper substrate and the lower substrate are moved in a staggered manner in a parallel direction to enable liquid crystals to have different orientations, brightness and color changes are observed through a polaroid, monitoring signals of the object to be measured are fed back, the brightness and color change degree depends on the anchoring type of liquid crystal molecules and the size of sequence parameters, and the brightness and color change is more obvious along with the increase of the moving distance of the object to be measured.
Specifically, if the bolt on the flange is required to be monitored to be loosened during the working process of the device, such as a flange connection or a flange joint commonly seen in mechanical devices, so as to prevent the device from being broken due to the loosening of the bolt, the upper substrate and the lower substrate of the sensor are respectively fixed on the flange and the bolt, when the bolt is loosened, the upper substrate of the sensor moves along with the bolt, and due to the silicon dioxide bead interval between the substrates, the upper substrate moves in the direction parallel to the lower substrate. In addition, in some experimental equipment or precision instruments with guide rails, it is also necessary to ensure that samples are not damaged by micro-movement of the guide rails during the operation of the equipment, and the position change of the guide rails can be monitored in real time by fixing the sensor in the same manner.
The currently used displacement sensors are single in function and high in installation condition, and if the measurement space is required to be large, the resolution is low, and the displacement sensors can only be used for static measurement but cannot realize dynamic monitoring, and the application range of the displacement sensors is limited. The sensor provided by the invention has no limitation on the conditions.
The early warning module converts the optical signal into an electrical signal for accurate early warning and monitoring, as shown in fig. 6, specifically includes: initializing an early warning module, monitoring the object movement value in real time, judging whether the object movement value exceeds the early warning value, if so, carrying out early warning, resetting after early warning, and if not, continuing to carry out real-time monitoring.
As shown in fig. 5, in the initial state, since the groove arrays on the two substrates are perpendicular to each other, the liquid crystal molecules near the surfaces of the substrates are aligned along the directions of the surface grooves. The liquid crystal molecules located between the two substrates are forced into a twisted state due to the inherent viscosity of the liquid crystal itself. The state of the liquid crystal molecules is twisted, and light is also twisted as it passes through the liquid crystal molecules. As shown in fig. 3 and 4, when the liquid crystal molecules move with the monitoring object, an interaction force is generated between the liquid crystal molecules, and the initial twist structure of the liquid crystal layer is destroyed under the anchoring action of the substrate surface, so that the liquid crystal molecules are rearranged. After the light in this state passes through the lower polarizer, the liquid crystal molecules are no longer twisted and conducted to polarized light. However, the polarizer allows only a light component of a certain fixed direction to pass therethrough, and the polarization direction of the upper polarizer is perpendicular to that of the lower polarizer, so that light cannot pass therethrough. When the movement degree (or the number of times) of the object is different, the rearrangement degree of the liquid crystal molecules is also different, namely the anchoring type (shown in fig. 2) and the degree and the number of the torsion light rays are different, different brightness and colors are displayed on a screen, and the aim of early warning and monitoring is fulfilled.
In the specific implementation process, the liquid crystal sensor can provide two modes of rough early warning monitoring and precise early warning monitoring:
in the rough early warning mode, the approximate distance of the movement of the object to be measured is measured by observing the brightness, the color change degree or the frequency of the display area of the sensor. Under the condition that accurate early warning is not needed, micro-movement signals of the monitored object to be detected can be provided rapidly.
In the accurate early warning mode, an initial zero scale value of the liquid crystal molecular orientation is preset. When the orientation degree of the liquid crystal is changed, the corresponding monitoring value is also changed, and the early warning and monitoring module early warns in real time.
In addition, the rough monitoring can be performed by adjusting the set value of the early warning module. For example, the early warning module performs early warning only when the brightness and color of the display area change more than a certain number of times or the monitoring early warning value exceeds a set value. When no person is on duty, the communication function of the early warning module is used for remote control, so that the functions of sensor detection, self-diagnosis, data storage processing and the like are realized.
In view of the reversibility of the liquid crystal molecular orientation regulation, the device can be reused.
While the foregoing embodiments have been described in detail in connection with the embodiments of the invention, it should be understood that the foregoing embodiments are merely illustrative of the invention and are not intended to limit the invention, and any modifications, additions, substitutions and the like made within the principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. The micro-movement early-warning liquid crystal sensor is characterized by comprising an upper glass substrate and a lower glass substrate which are oppositely arranged, wherein groove arrays which are mutually perpendicular are arranged on the inner surfaces of the upper glass substrate and the lower glass substrate which are opposite to each other, a liquid crystal interlayer is arranged between the upper glass substrate and the lower glass substrate, and the liquid crystal interlayer is sealed through a sealing layer; the upper surface of the upper glass substrate is provided with an upper polaroid, the lower surface of the lower glass substrate is provided with a lower polaroid, and a backlight plate is arranged below the lower polaroid.
2. The micro-movement early-warning liquid crystal sensor according to claim 1, wherein the lower surface of the upper glass substrate and the upper surface of the lower glass substrate are covered with an alignment film, and the alignment direction of the alignment film is consistent with the direction of the grooves on the adjacent substrates.
3. The micro-mobile early warning liquid crystal sensor according to claim 1, wherein the upper glass substrate has a display function, and a display area is built-in or externally connected with an early warning monitoring module.
4. The micro-motion warning liquid crystal sensor according to claim 1, wherein the side length of the surface groove array is 50-300 μm, the interval between adjacent arrays is 20-50 μm, and the distance between the boundary array and the edge of the substrate is 2-5mm.
5. The micro-motion warning liquid crystal sensor of claim 1, wherein the thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer comprises thermotropic liquid crystal and lyotropic liquid crystal.
6. The micro-motion warning liquid crystal sensor according to claim 1, wherein silica beads with diameters corresponding to the thickness of the liquid crystal interlayer are fixed between the upper glass substrate and the lower glass substrate.
7. A method for manufacturing a micro-mobile early warning liquid crystal sensor according to any one of claims 1 to 6, comprising the steps of:
diamond particles with the same diameter are fixed on the film, and the glass substrate is pressed at constant pressure and speed to rub back and forth on the film for a plurality of times, so that a regular surface groove array is obtained; or, covering a layer of film with induced liquid crystal orientation on the surface of the substrate, and then carrying out surface treatment;
covering a film with induced liquid crystal orientation on the treated surface of the glass substrate;
the processed surfaces of the two glass substrates are placed oppositely, the two glass substrates are sealed through a sealing layer, and a liquid crystal injection opening is reserved;
injecting liquid crystal into the interlayer by capillary effect, and standing for 5-10 min to fill the whole interlayer with liquid crystal;
and installing an early warning and monitoring module, a polaroid and a backlight plate.
8. The micro-motion warning liquid crystal sensor according to claim 7, wherein the diameter of the diamond particles is 10-100 μm and the pressure is 1-5N/cm 2 The friction speed is 1-5cm/s, and the friction times are 5-20 times.
9. The method for using a micro-motion warning liquid crystal sensor according to any one of claims 1 to 6, wherein the sensor is installed at a position where relative motion of an object occurs, as the object to be monitored moves slightly, upper and lower substrates of the sensor move in a staggered manner in a parallel direction to cause different orientations of liquid crystals, brightness and color changes are observed through a polarizer, monitoring signals of the object to be detected are fed back, the brightness and color change degree depends on the anchoring type of liquid crystal molecules and the magnitude of sequence parameters, and the brightness and color changes are more obvious as the moving distance of the object to be detected is increased.
10. The method for using a micro-mobile early-warning liquid crystal sensor according to claim 9, wherein the early-warning module converts an optical signal into an electrical signal for accurate early-warning monitoring, and specifically comprises: initializing an early warning module, monitoring the moving value of the object in real time, judging whether the moving value exceeds the early warning value, if so, carrying out early warning, resetting after early warning, and if not, continuing to carry out real-time monitoring.
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