Intelligent contact lens for intraocular pressure detection

Abstract

The utility model relates to an intelligent contact lens for intraocular pressure detection, which comprises a substrate layer and a plurality of bubble holes uniformly distributed on the substrate layer close to the outer edge of an inner ring; the self-lubricating layer is arranged on the outer side of the substrate layer and forms a double-lens structure with the substrate layer; the sensing layer is embedded between the self-lubricating layer and the substrate layer; the sensing layer comprises an ion piezoelectric flexible sensor and an integrated chip, and the ion piezoelectric flexible sensor and the integrated chip are connected through stretchable interconnected wires; according to the utility model, the ion piezoelectric flexible sensor is embedded in the middle of the double-layer lens, and the self power generation of the ion piezoelectric flexible sensor and the bubble hole design of the substrate layer are utilized, so that the physiological status of the glasses can be wirelessly, continuously and noninvasively monitored while the good biological compatibility is realized; and detecting biomarkers associated with eye and other diseases, facilitating clinical application of the contact lens sensor.

Description

Technical Field

[0001] The utility model relates to the technical field of intraocular pressure detection, in particular to an intelligent contact lens for intraocular pressure detection. Background Art

[0002] Traditional intraocular pressure testing needs to be performed in hospitals, which is not only time-consuming for doctors and patients, but also difficult to achieve 24-hour continuous testing. It cannot accurately grasp the fluctuation law of intraocular pressure, and the currently commonly used intraocular pressure measurement and monitoring technology has defects in size, measurement accuracy, power consumption and intelligence. The current research hotspot is to miniaturize the intraocular pressure sensor and wear it as a contact lens, which has the advantages of convenience, comfort and non-invasiveness. However, there are many challenges in the design and production of smart contact lenses. Flexibility, visibility, hydrophilicity and oxygen permeability should be considered when making smart contact lenses. At the same time, an external battery power supply or receiver is required, which is impractical for use in real life. Existing intraocular pressure detection often finds it difficult to meet the above requirements at the same time, and mostly focuses on one or several advantages; and traditional sensors used for intraocular pressure detection have the following disadvantages:

[0003] 1. It is necessary to install a power supply and storage system, which may easily cause heating of the overall components and energy loss.

[0004] 2. The structure is too complicated, which increases the burden on the eyes.

[0005] 3. The signal transmission lacks a sufficiently stable method, which easily leads to the loss of sensor signals. Utility Model Content

[0006] To this end, the technical problem to be solved by the utility model is to overcome the problems of intraocular pressure detection in the prior art. By providing an intelligent contact lens for intraocular pressure detection, the self-generation of the ion piezoelectric flexible sensor and the bubble hole design of the substrate layer are utilized to achieve wireless, continuous and non-invasive monitoring of the physiological condition of the glasses while having good biocompatibility.

[0007] In order to solve the above technical problems, the utility model provides a smart contact lens for intraocular pressure detection, comprising:

[0008] A substrate layer, wherein a plurality of air bubbles are evenly distributed near the outer edge of the inner circle of the substrate layer;

[0009] A self-lubricating layer, which is disposed on the outer side of the substrate layer and forms a double-lens structure with the substrate layer;

[0010] The sensing layer is embedded between the self-lubricating layer and the substrate layer; the sensing layer includes an ion piezoelectric flexible sensor and an integrated chip, the ion piezoelectric flexible sensor is used to sense the surface impedance change of the corneal tissue caused by the change of intraocular pressure and generate a voltage signal; the integrated chip is used to analog amplify the low-power voltage signal, and then convert the analog signal into a digital signal and store it; the ion piezoelectric flexible sensor is connected to the integrated chip through a stretchable interconnected wire.

[0011] In one embodiment of the utility model, the ionic piezoelectric flexible sensor is a snowflake structure, symmetrically distributed on the sensing layer. The design of the snowflake structure avoids voltage errors that may be caused by uneven distribution of ionic liquids, while allowing the wearer to have no visual obstruction during use, and the edges and corners of the snowflake increase the contact area between the sensor and the lens, expand the sensing range, and make the connection between the two closer, thereby improving the stability of the signal.

[0012] In one embodiment of the present invention, the wire is a horseshoe-shaped structure.

[0013] In one embodiment of the present invention, the ionic piezoelectric flexible sensor includes an electrolyte layer and graphene electrode layers arranged on the upper surface and the lower surface of the electrolyte layer.

[0014] In one embodiment of the present invention, the electrolyte layer is composed of ionic liquid and thermoplastic polymer.

[0015] In one embodiment of the present invention, a plurality of air bubble holes are provided in the inner circle of the substrate layer.

[0016] In one embodiment of the present invention, the substrate layer is a lower lens made of a high molecular hydrophilic material polyvinyl alcohol hydrogel.

[0017] In one embodiment of the present invention, the self-lubricating layer includes an upper lens made of a high molecular hydrophilic material polyvinyl alcohol hydrogel and a lubricating coating disposed on the surface of the upper lens.

[0018] In one embodiment of the present invention, the integrated chip includes a silicon substrate, a signal amplification system and a signal analysis system disposed on the silicon substrate, and a biocompatible polymer disposed on the outer side of the silicon substrate for encapsulating the signal amplification system and the signal analysis system.

[0019] In one embodiment of the present invention, the signal amplification system is a signal simulation amplifier.

[0020] In one embodiment of the utility model, the signal analysis system is a micro information processing instrument.

[0021] In one embodiment of the present invention, the micro information processor is connected to a computer via Bluetooth to achieve signal transmission.

[0022] The above technical solution of the utility model has the following advantages compared with the prior art:

[0023] The utility model discloses an intelligent contact lens for intraocular pressure detection. The ion piezoelectric flexible sensor does not require power and exhibits high sensitivity, and the bubble hole design of the substrate layer realizes wireless, continuous and non-invasive monitoring of the physiological condition of the glasses while having good biocompatibility, as well as detection of biomarkers related to the eye and other diseases, thereby promoting the clinical application of contact lens sensors. At the same time, the compact layout and double-layer lens design enable the ion piezoelectric flexible sensor to be embedded in the contact lens, avoiding direct contact of these components with the ocular surface, which may cause potential irritation to the eye. The bubble hole design on the substrate layer is conducive to reducing the interference of surface friction on the sensing signal, has excellent oxygen permeability and wettability, alleviates the problem of corneal hypoxia, and avoids eye discomfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0025] Figure 1 It is a schematic structural diagram of a contact lens for intraocular pressure detection in a preferred embodiment of the utility model;

[0026] Figure 2 yes Figure 1 A schematic structural diagram of a substrate layer of a contact lens for intraocular pressure detection is shown;

[0027] Figure 3 yes Figure 1 The working principle block diagram of the sensing layer of the contact lens for intraocular pressure detection is shown;

[0028] Explanation of the reference numerals in the specification: 1. substrate layer; 11. inner ring; 12. outer ring; 13. bubble holes; 2. self-lubricating layer; 3. sensing layer; 31. ion piezoelectric flexible sensor; 32. integrated chip; 33. wire. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0030] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0031] Reference Figure 1 and 2 As shown, the utility model is a smart contact lens for intraocular pressure detection, comprising: a substrate layer 1, on which a circle of bubble holes 13 are distributed between an inner circle 11 and an outer circle 12; a self-lubricating layer 2, wherein the self-lubricating layer 2 is arranged on the outer side of the substrate layer 1 and forms a double-lens structure with the substrate layer 1; a sensing layer 3, embedded between the self-lubricating layer 2 and the substrate layer 1; the sensing layer 3 comprises an ion piezoelectric flexible sensor 31 and an integrated chip 32, wherein the ion piezoelectric flexible sensor 31 is used to sense the surface impedance change of the corneal tissue caused by the change of the intraocular pressure and generate a voltage signal; the integrated chip 32 is used to analogically amplify the low-power voltage signal, and then convert the analog signal into a digital signal and store it; the ion piezoelectric flexible sensor 31 is connected to the integrated chip 32 via a stretchable interconnected wire 33.

[0032] Preferably, the ionic piezoelectric flexible sensor 31 is a snowflake structure, symmetrically distributed on the sensing layer 3. The design of the snowflake structure ionic piezoelectric flexible sensor 31 avoids the voltage error that may be caused by the uneven distribution of ionic liquid, and at the same time, the wearer has no visual obstruction during use. The edges and corners of the snowflake increase the contact area between the sensor and the lens, expand the sensing range, and make the connection between the two closer, thereby improving the stability of the signal;

[0033] Preferably, the wire 33 is a horseshoe-shaped structure. Since the contact lens only needs the optical zone of the light entering it to be unaffected, it will not block the user's vision, so the wire 33 structure design performed on the middle sensing layer, on this theoretical basis, connects the snowflake structure sensor to the integrated chip 32 through the wire 33, and connects the two through the wire 33 of the stretchable interconnected horseshoe structure, so that the electronic components embedded in the double lens allow the device to be bent as needed to insert or remove it.

[0034] Preferably, the ionic piezoelectric flexible sensor 31 includes an electrolyte layer and a graphene electrode layer arranged on the upper and lower surfaces of the electrolyte layer. The electrolyte layer is composed of an ionic liquid and a thermoplastic polymer. By utilizing the unbalanced ion distribution formed between the symmetrical electrodes, the ionic piezoelectric flexible sensor 31 generates a voltage signal without an additional power supply, thereby realizing self-powered power supply. The thickness of the electrolyte layer will affect the migration rate and path of the ions. If the thickness of the electrolyte layer is too small, the rate of ion migration to the electrode interface will be reduced. If the thickness is too large, the time for ion migration to the electrode interface will be relatively long, resulting in problems such as untimely voltage response and low sensitivity. Therefore, an electrolyte layer with a suitable thickness exhibits good mechanical flexibility and high voltage stability, and exhibits excellent performances such as high sensitivity, high signal-to-noise ratio, high sensor signal recognition, and efficient voltage response. In this embodiment, the thickness of the electrolyte layer is 100 to 220 μm. In addition, using reduced graphene oxide with high conductivity and relatively high porosity as the electrode layer material can increase the space for ion accumulation and contact, and provide additional channels for ion transmission, thereby obtaining an electrolyte layer with high sensitivity.

[0035] In this embodiment, the electrolyte layer is prepared by compounding an ionic liquid and a thermoplastic polymer, so that the electrolyte layer has both the good mechanical properties of the polymer and the high voltage stability of the ionic liquid, while avoiding the leakage problem that may exist when the ionic liquid is used as an electrolyte material.

[0036] Preferably, the substrate layer 1 is a lower lens made of a high molecular weight hydrophilic material polyvinyl alcohol hydrogel. This design is conducive to biocompatibility with the eye, and the bubble hole 13 design is conducive to reducing the interference of surface friction on the sensor signal, has excellent oxygen permeability and wettability, reduces the problem of corneal hypoxia, and avoids eye discomfort.

[0037] Preferably, the self-lubricating layer 2 comprises an upper lens made of a high molecular weight hydrophilic material polyvinyl alcohol hydrogel and a lubricating coating disposed on the surface of the upper lens. The lubricating coating has the characteristics of low friction and wear resistance, high bonding strength, and is not easy to fall off.

[0038] In this embodiment, the integrated chip 32 includes a silicon substrate, a signal amplification system and a signal analysis system disposed on the silicon substrate, and a biocompatible polymer disposed on the outer side of the silicon substrate for encapsulating the signal amplification system and the signal analysis system.

[0039] Preferably, the signal amplification system is a signal analog amplifier that can take a low power analog signal as input and output a more powerful version of the same signal.

[0040] Preferably, the signal analysis system is a micro information processor, which is connected to a computer via Bluetooth to achieve signal transmission. By using Bluetooth, there is no need to install a wire 33 or an electromagnetic coupling coil, and accurate real-time monitoring of intraocular pressure is achieved while reducing the burden on the contact lens structure.

[0041] The process of contact lenses for intraocular pressure detection based on the above structure is as follows:

[0042] like Figure 3 As shown, when the intraocular pressure increases, the ionic piezoelectric flexible sensor 31 of the sensing layer 3 is used to sense the change in surface impedance of the corneal tissue caused by the change in intraocular pressure and generate a voltage signal, and obtain 3 to 6 voltage values, which are transmitted to the signal analog amplifier through the wire 33. The signal analog amplifier amplifies the data and transmits the signal to the micro information processor at the output end through the wire 33, converts the waveform into digital and stores it. The micro information processor averages the 3 to 6 data obtained, and then displays the average value on the LCD screen of the computer through the Bluetooth connection, that is, the millimeters of mercury value of the intraocular pressure.

[0043] Among them, the principle of the ion piezoelectric flexible sensor 31 of the sensing layer 3 generating a voltage signal is as follows: when the ion piezoelectric flexible sensor 31 is in an unstressed state, the anions and cations of the ionic liquid in the electrolyte layer are evenly distributed in the electrolyte layer, and no voltage signal is generated at this time; when the ion piezoelectric flexible sensor 31 is in a stressed state (increased intraocular pressure), the anions and cations on the compression side of the electrolyte layer move toward the stretching side. Due to the difference in the movement rate of the anions and cations, the anions and cations on the stretching side and the compression side are unbalanced, resulting in a voltage signal between the upper and lower electrodes located on the upper and lower surfaces of the electrolyte layer, thereby realizing intraocular pressure measurement without power supply.

[0044] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. A smart contact lens for intraocular pressure detection, characterized in that: include: A substrate layer, wherein a plurality of air bubbles are evenly distributed near the outer edge of the inner circle of the substrate layer; A self-lubricating layer, which is disposed on the outer side of the substrate layer and forms a double-lens structure with the substrate layer; The sensing layer is embedded between the self-lubricating layer and the substrate layer; the sensing layer includes an ion piezoelectric flexible sensor and an integrated chip, the ion piezoelectric flexible sensor is used to sense the surface impedance change of the corneal tissue caused by the change of intraocular pressure and generate a voltage signal; the integrated chip is used to analog amplify the low-power voltage signal, and then convert the analog signal into a digital signal and store it; the ion piezoelectric flexible sensor is connected to the integrated chip through a stretchable interconnected wire.

2. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The ionic piezoelectric flexible sensor is a snowflake structure and is symmetrically distributed on the sensing layer.

3. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The conductor is in a horseshoe-shaped structure.

4. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The ionic piezoelectric flexible sensor comprises an electrolyte layer and graphene electrode layers arranged on the upper surface and the lower surface of the electrolyte layer.

5. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The substrate layer is a lower lens made of a high molecular hydrophilic material polyvinyl alcohol hydrogel.

6. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The self-lubricating layer comprises an upper lens made of a high molecular hydrophilic material polyvinyl alcohol hydrogel and a lubricating coating arranged on the surface of the upper lens.

7. The smart contact lens for intraocular pressure detection according to claim 1, characterized in that: The integrated chip comprises a silicon substrate, a signal amplification system and a signal analysis system arranged on the silicon substrate, and a biocompatible polymer arranged on the outer side of the silicon substrate for encapsulating the signal amplification system and the signal analysis system.

8. The smart contact lens for intraocular pressure detection according to claim 7, characterized in that: The signal amplification system is a signal simulation amplifier.

9. The smart contact lens for intraocular pressure detection according to claim 7, characterized in that: The signal analysis system is a micro information processor, and the micro information processor is connected to a computer via Bluetooth to achieve signal transmission.

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