Wireless passive resonance sensor and contact lens for intraocular pressure monitoring

Abstract

A wireless passive resonance sensor and contact lens for intraocular pressure monitoring comprises a contact lens body which is used for packaging a sensor assembly and serves as a substrate of the sensor. The first spiral inductor is arranged in the contact lens body; the middle elastic dielectric layer covers the first spiral inductor and is used for forming a deformable dielectric medium; the second spiral inductor is arranged on the middle-layer elastic dielectric layer, is opposite to the first spiral inductor and forms an inductor assembly with the first spiral inductor; wherein the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor jointly form a capacitor and equivalently form a serial L-C-L resonant circuit, and the change of intraocular pressure is responded through the change of resonant frequency of the resonant circuit, so that passive wireless monitoring is realized. The design optimizes the preparation process, reduces the cost, improves the signal stability, is suitable for 24-hour continuous monitoring, and provides a powerful tool for early diagnosis and intervention of glaucoma.

Description

Technical Field

[0001] The invention relates to the technical field of intraocular pressure sensors and contact lenses, and in particular to a wireless passive resonant sensor and contact lenses for intraocular pressure monitoring. Background Art

[0002] Glaucoma is a type of ophthalmic disease characterized by pathological increase in intraocular pressure (IOP), and its typical manifestations include optic atrophy and visual field loss. In the diagnosis and treatment of glaucoma, intraocular pressure is the most important clinical basis. However, due to the circadian rhythm of intraocular pressure, it is difficult to fully reflect its true fluctuations through a single measurement. Some patients have intraocular pressure within the normal range in outpatient tests, but still have visual field defects. This may be because the intraocular pressure of the patient fluctuates significantly during non-outpatient time periods, even exceeding normal values. Therefore, 24-hour continuous monitoring of intraocular pressure is of great clinical significance for the early diagnosis and intervention of glaucoma.

[0003] At present, the tonometers commonly used in clinical practice mainly include Goldmann applanation tonometer, jet tonometer and rebound tonometer. However, these instruments cannot meet the demand for 24-hour continuous monitoring of intraocular pressure. In the existing technical solutions, the equipment that can achieve 24-hour continuous monitoring of intraocular pressure mainly includes implantable intraocular pressure sensors and non-invasive intraocular pressure sensors. Implantable intraocular pressure sensors require surgery to implant the device into the eye. This method inevitably causes certain trauma to the patient, limiting its extensive clinical application.

[0004] In recent years, the rapid development of contact lens manufacturing technology and the widespread application of flexible electronic technology in the field of sensors have provided new possibilities for integrating flexible intraocular pressure sensors into contact lenses and realizing continuous intraocular pressure monitoring. Among them, a feasible technical solution is based on the principle of inductive coupling. Through a resonant unit composed of an inductor and a capacitor integrated in the contact lens, the change in resonant frequency is used to detect changes in intraocular pressure. Based on this principle, some related studies have made initial progress. However, the current contact lens pressure sensors based on capacitor-inductor resonant structure generally have complex structures and high difficulty in preparation, which seriously limits the feasibility of their large-scale application.

[0005] Therefore, there is an urgent need to develop a contact lens-type flexible sensor that is simple in structure, easy to prepare, suitable for mass production, and capable of 24-hour continuous intraocular pressure monitoring to meet the clinical needs of glaucoma diagnosis and treatment.

[0006] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0007] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a wireless passive resonant sensor for intraocular pressure monitoring.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] A wireless passive resonant sensor for intraocular pressure monitoring, comprising:

[0010] A contact lens body, used to encapsulate the sensor assembly and serve as a substrate for the sensor;

[0011] A first spiral inductor is disposed in the contact lens body;

[0012] A middle elastic dielectric layer, covering the first spiral inductor and used to form a deformable dielectric;

[0013] A second spiral inductor is disposed on the middle elastic dielectric layer, opposite to the first spiral inductor and forming an inductor component;

[0014] The first spiral inductor, the middle elastic dielectric layer and the second spiral inductor together constitute a capacitor and equivalently form a series LCL resonant circuit, which responds to changes in intraocular pressure through changes in the resonant frequency of the resonant circuit.

[0015] Furthermore, the contact lens body comprises a first flexible packaging layer and a second flexible packaging layer, and the first spiral inductor, the middle elastic dielectric layer, and the second spiral inductor are stacked and arranged between the first flexible packaging layer and the second flexible packaging layer.

[0016] Furthermore, the first spiral inductor and the second spiral inductor are both made of flexible materials with a thickness in the range of 5-15 μm; and the thickness of the middle elastic dielectric layer is in the range of 20-50 μm.

[0017] Furthermore, the first spiral inductor and the second spiral inductor have the same shape and are plane symmetrical; the center positions of the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor overlap with the contact lens body.

[0018] Furthermore, the contact lens body includes a central circular area covering the pupil and a peripheral area, and the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor are located in the peripheral area of ​​the contact lens body; preferably, the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor are distributed between 3.5 and 6.5 mm from the center point of the contact lens.

[0019] Furthermore, the equivalent inductance value of the first spiral inductor and the second spiral inductor does not exceed 5H, and the capacitance value does not exceed 25pF.

[0020] Furthermore, the first spiral inductor and the second spiral inductor are formed by patterned metal The electrode material, and the current directions in the first spiral inductor and the second spiral inductor are opposite, clockwise and counterclockwise respectively, forming a quasi-closed large coil system of current.

[0021] Furthermore, the first spiral inductor and the second spiral inductor are prepared into a symmetrical structure through planar micro-nano processing technology, and the capacitive intraocular pressure sensor is formed by folding the second spiral inductor over the first spiral inductor and sandwiching the middle elastic dielectric layer between the two.

[0022] Furthermore, the material of the contact lens body is selected from one or more of polyhydroxyethyl methacrylate (pHEMA), polydimethylsiloxane (PDMS), and hydroxyethyl methacrylate (HEMA), and the contact lens body is molded by hot pressing of a mold.

[0023] Furthermore, the middle elastic dielectric layer is composed of an elastic non-conductive film, and its material is a biocompatible material selected from one or more of polydimethylsiloxane (PDMS), elastic silicone (Ecoflex), and styrene-butadiene-styrene copolymer (SBS).

[0024] A contact lens is provided with the wireless passive resonant sensor for intraocular pressure monitoring.

[0025] The present invention has the following beneficial effects:

[0026] In view of the limitations and shortcomings of the existing wireless passive intraocular pressure sensors in the preparation process, the present invention proposes a wireless passive resonant sensor for intraocular pressure monitoring, which is an intraocular pressure monitoring sensor embedded in a contact lens. The improved structural design of the present invention provides a simple-structured, easy-to-prepare capacitive-inductor resonant contact lens pressure sensor, which achieves efficient and continuous intraocular pressure monitoring, optimizes its performance and simplifies the preparation process. Through the ingenious double-helix inductor design and the introduction of an elastic dielectric layer, the sensor is equivalent to a series LCL resonant circuit, and the change in resonant frequency is used to monitor intraocular pressure. This design not only improves the stability and transmission efficiency of the signal, but also avoids the need for complex lead connections and simplifies the preparation process.

[0027] Further, the present invention prepares the first spiral inductor and the second spiral inductor by using patterned metal electrode materials, and makes the current directions opposite (clockwise and counterclockwise) to form a quasi-closed large coil system. This design significantly reduces the attenuation during the transmission of radio frequency signals, improves the signal transmission distance, and optimizes the operating frequency of the capacitor-inductor resonator, so that it can work efficiently at a lower frequency. The present invention uses planar micro-nano processing technology to prepare symmetrical spiral inductor coils, and places the second spiral inductor above the first spiral inductor through a folding process, and then sandwiches the middle elastic dielectric layer, thereby realizing the rapid assembly of the capacitive intraocular pressure sensor. This design not only simplifies the preparation process and avoids complex wire bonding operations, but also greatly reduces the difficulty and cost of preparation, improves processing efficiency, and is particularly suitable for mass production of flexible circuits, effectively solving the problems of complex structure and difficult preparation of existing contact lens pressure sensors, significantly improving the detection accuracy and performance stability of the sensor, and better meeting the clinical needs of intraocular pressure monitoring.

[0028] The main advantages of the embodiments of the present invention also include:

[0029] The first spiral inductor, deformable dielectric layer and second spiral inductor integrated in the contact lens are all made of flexible materials, which can ensure to the greatest extent that the device itself does not affect the elasticity of the overall contact lens, thereby improving the wearing comfort of the user. At the same time, the device is more conformal to the eyeball, can respond quickly to changes in intraocular pressure, and has good sensing performance.

[0030] The sensor device is based on the principle of inductive coupling. It derives the intraocular pressure by monitoring the size of the resonant frequency. The measurement process can be accessed wirelessly through the reading circuit without the need for additional connecting wires. It is easy to use and can be used in situations where the eyes are closed, such as when sleeping at night.

[0031] The thickness of the first spiral inductor and the second spiral inductor is within the range of 5-15 μm, and the thickness of the deformable dielectric layer is within the range of 20-50 μm, which can ensure that the final contact lens intraocular pressure sensor does not become thicker due to the introduction of the sensor device, thereby ensuring wearing comfort.

[0032] The design of pure patterned sensor devices fully utilizes the characteristics of the structure itself, does not require the introduction of additional IC chips or components, has a simple structure and is easy to prepare. Traditional metal materials such as copper, silver, and gold with excellent conductive properties can be used to effectively improve the inductive coupling efficiency and ensure signal stability.

[0033] The contact lens substrate is made of a flexible biocompatible material, which ensures that the contact lens-type intraocular pressure sensor of the present invention has high safety and is suitable for patients to wear for a long time.

[0034] The sensor can use flexible circuit board printing or photolithography technology to prepare the circuit, which simplifies the manufacturing process, improves production efficiency, and significantly reduces manufacturing costs; during the assembly process, it can be completed through simple alignment and stacking operations without the need for complex lead connections, which greatly improves the yield rate and is suitable for large-scale batch production.

[0035] In summary, the present invention has significant advantages in structural design, performance optimization, material selection and preparation process, and provides a practical solution for the practical application of contact lens pressure sensors.

[0036] Other beneficial effects of the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a schematic diagram of the structure layering of a contact lens type intraocular pressure sensor according to an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of a spiral inductor of a contact lens-type intraocular pressure sensor according to an embodiment of the present invention;

[0039] Figure 3 is an equivalent circuit diagram of the contact lens type intraocular pressure sensor in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0041] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection can be used for fixing as well as for coupling or communication.

[0042] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0044] See also Figures 1 to 3 The embodiment of the present invention provides a wireless passive resonant sensor for intraocular pressure monitoring, including: a contact lens body 1, used to encapsulate the sensor component and serve as the substrate of the sensor; a first spiral inductor 22, arranged in the contact lens body; a middle elastic dielectric layer 3, covering the first spiral inductor 22, forming a deformable dielectric; a second spiral inductor 21, arranged on the middle elastic dielectric layer 3, opposite to the first spiral inductor 22 and forming an inductor component; wherein the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 together constitute a capacitor 4, and equivalently form a series LCL resonant circuit, which responds to changes in intraocular pressure by changing the resonant frequency of the resonant circuit. The resonant frequency of the LCL resonant circuit (That is, the resonant frequency f and Wherein, L2 is a combination of the equivalent inductance 2 of the first spiral inductor 22 and the second spiral inductor 21; C is the capacitance between the first spiral inductor 22 and the second spiral inductor 21.

[0045] like Figure 1As shown, in a preferred embodiment, the contact lens body includes a first flexible packaging layer 12 and a second flexible packaging layer 11, and the first spiral inductor 22, the middle elastic dielectric layer 3, and the second spiral inductor 21 are stacked and arranged between the first flexible packaging layer 12 and the second flexible packaging layer 11. Further preferably, the first spiral inductor 22 and the second spiral inductor 21 are both made of flexible materials with a thickness in the range of 5-15 μm; the thickness of the middle elastic dielectric layer 3 is in the range of 20-50 μm.

[0046] In a preferred embodiment, the material of the contact lens body is selected from one or more of polyhydroxyethyl methacrylate (pHEMA), polydimethylsiloxane (PDMS), and hydroxyethyl methacrylate (HEMA). The contact lens body is formed by hot pressing and heating of a mold. The middle elastic dielectric layer 3 is composed of an elastic non-conductive film, and its material is a biocompatible material, selected from one or more of polydimethylsiloxane (PDMS), elastic silicone (Ecoflex), and styrene-butadiene-styrene copolymer (SBS).

[0047] like Figure 1 As shown, in a preferred embodiment, the first spiral inductor 22 and the second spiral inductor 21 have the same shape and are plane symmetrical. The center positions of the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 coincide with the contact lens body. The contact lens body includes a central circular area covering the pupil and a peripheral area, and the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 are located in the peripheral area of ​​the contact lens body. Further preferably, the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 are distributed between 3.5 and 6.5 mm from the center point of the contact lens.

[0048] In some embodiments, the equivalent inductance of the first spiral inductor 22 and the second spiral inductor 21 does not exceed 5H, and the capacitance does not exceed 25pF.

[0049] like Figure 2 As shown, in a preferred embodiment, the first spiral inductor 22 and the second spiral inductor 21 use patterned metal electrode materials, and the current directions in the first spiral inductor 22 and the second spiral inductor 21 are opposite, namely clockwise and counterclockwise, respectively, forming a quasi-closed large coil system of current.

[0050] like Figure 1 and Figure 2As shown, in a preferred embodiment, the first spiral inductor 22 and the second spiral inductor 21 are prepared into a symmetrical structure by planar micro-nano processing technology, and the second spiral inductor 21 is folded over the first spiral inductor 22 and the middle elastic dielectric layer 3 is sandwiched between the two to form a capacitive intraocular pressure sensor.

[0051] An embodiment of the present invention further provides a contact lens having the wireless passive resonant sensor for intraocular pressure monitoring according to any of the aforementioned embodiments.

[0052] The wireless passive resonant sensor of the present invention integrates the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor into the contact lens body to form a new type of intraocular pressure monitoring device with simple structure and efficient function. The sensor is constructed of flexible materials to ensure the comfort and biocompatibility of wearing, while not affecting the elasticity and overall performance of the contact lens, so that it can conform to the surface of the eyeball, thereby achieving a rapid response to changes in intraocular pressure. Through the ingenious double-helix inductor design and the introduction of the elastic dielectric layer, the sensor can be equivalent to a series LCL resonant circuit, and the change of the resonant frequency is used to monitor the intraocular pressure. This design not only improves the stability and transmission efficiency of the signal, but also avoids the need for complex lead connection and simplifies the preparation process. The sensor is based on the working principle of wireless passiveness, does not require an external power supply or wire connection, and can achieve continuous monitoring in any wearing state (including sleep), which greatly improves the convenience and applicability of use. Furthermore, the sensor component prepared by conventional micro-nano processing technology, combined with the contact lens body formed by mold hot pressing, realizes low-cost and high-efficiency mass production, laying a solid foundation for the wide application of this technology.

[0053] The preferred embodiment uses patterned metal electrode materials to prepare the first spiral inductor and the second spiral inductor, and makes the current directions opposite (clockwise and counterclockwise) to form a quasi-closed large coil system. This design significantly reduces the attenuation of the radio frequency signal during transmission, improves the signal transmission distance, and optimizes the operating frequency of the capacitor-inductor resonator, so that it can work efficiently at a lower frequency. The preferred embodiment uses planar micro-nano processing technology to prepare a symmetrical spiral inductor coil, and places the second spiral inductor above the first spiral inductor through a folding process, and then sandwiches the middle elastic dielectric layer, thereby realizing the rapid assembly of the capacitive intraocular pressure sensor. This design not only simplifies the preparation process and avoids complex wire bonding operations, but also greatly reduces the difficulty and cost of preparation, improves processing efficiency, and is particularly suitable for mass production of flexible circuits. It effectively solves the problems of complex structure and difficult preparation of existing contact lens pressure sensors, significantly improves the detection accuracy and performance stability of the sensor, and better meets the clinical needs of intraocular pressure monitoring.

[0054] The specific embodiments of the present invention are further described below.

[0055] The present invention proposes a wireless passive resonant sensor for intraocular pressure monitoring, the core structure of which includes two spiral inductor coils, a deformable dielectric layer and an adjustable capacitor formed based on the above structure. The sensor forms a series structure of the inductor coil and the capacitor, forming an LCL resonant oscillation circuit. Preferably, by using conventional micro-nano processing technology on a plane, two symmetrical spiral inductor coils are made, and the spiral coil on one side is folded to the top of the spiral coil on the other side, and then a deformable dielectric layer is sandwiched between the two spiral coils, thereby constructing a capacitive intraocular pressure sensor. This design has the advantages of simple structure, simple preparation process, and suitability for mass production, effectively reducing manufacturing costs, improving sensor detection accuracy, and being able to meet the performance requirements of intraocular pressure monitoring.

[0056] Specific as Figures 1 to 3 As shown, a flexible pressure sensor based on an LCL series circuit structure includes a contact lens body, a first spiral inductor 22, a middle elastic dielectric layer 3 (deformable dielectric layer) and a second spiral inductor 21; the contact lens body is used to encapsulate the first spiral electrode and the second spiral electrode; the center positions of the contact lens body, the first spiral electrode, the middle elastic dielectric layer 3 and the second spiral inductor 21 coincide with each other, and the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 are arranged in a uniform manner. two The spiral inductors 21 are all planar structures and are directly packaged in the contact lens body, which does not increase The original thickness of the contact lens body;

[0057] Furthermore, the first spiral inductor 22 and the second spiral inductor 21 have the same shape; the first spiral inductor 22 and the second spiral inductor 21 are plane-symmetrical.

[0058] Furthermore, the contact lens body includes a central circular area covering the pupil and a peripheral area; the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 are located in the peripheral area of ​​the contact lens body. After wearing, the position corresponding to the pupil is the central circular area of ​​the contact lens body, so the peripheral area where the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 are arranged will not affect pupil imaging.

[0059] The first spiral inductor 22, the second spiral inductor 21 and the middle elastic dielectric layer 3 together form a capacitor 4. Therefore, the first spiral inductor 22, the middle elastic dielectric layer 3 and the second spiral inductor 21 can be equivalent to a series LCL resonant circuit with a resonant frequency of Wherein, L2 is a combination of the equivalent inductance of the first spiral inductor 22 and the second spiral inductor 21 ; and C is the capacitance between the first spiral inductor 22 and the second spiral inductor 21 .

[0060] The present invention aims at the shortcomings of the existing wireless passive intraocular pressure sensor in the preparation process, especially the problem that the contact lens type intraocular pressure sensor has a complex structure and is difficult to prepare, and proposes an improved new structure, which adopts a design based on an LCL series circuit. The structure includes a first spiral inductor 22, a middle elastic dielectric layer 3 and a second spiral inductor 21. Figure 1 The overall structural schematic diagram of the sensor of the present invention is shown. Figure 3 Its equivalent circuit diagram is provided.

[0061] like Figure 2 As shown, the LCL structure of the present invention adopts a double spiral inductor design, and the second spiral inductor 21 is prepared together with the first spiral inductor 22, thereby avoiding the complex operation of wire bonding during the assembly process, and greatly reducing the difficulty of preparing the pressure sensor. In addition, the current directions in the second spiral inductor 21 and the first spiral inductor 22 are opposite, clockwise and counterclockwise respectively. This geometric layout forms a quasi-closed large coil system of current. Compared with the current in the same direction in the two spiral inductors, the design of the present invention is more conducive to the operation of the capacitor-inductor resonator at a lower frequency, thereby reducing the attenuation of the radio frequency signal during transmission and significantly improving the transmission distance of the signal.

[0062] In the intraocular pressure sensor structure of the present invention, the spiral inductor coil can be prepared by using the common micro-nano processing technology in the art, and an elastic dielectric material is filled between two layers of spiral inductor coils to form a capacitor 4. The dielectric material is a non-conductive elastic film, and the specific material selection can be determined according to the required capacitance value.

[0063] In some preferred embodiments, the present invention uses flexible biocompatible materials as contact lenses. IOP Sensor The substrate of the device, such as polyhydroxyethyl methacrylate (pHEMA), polydimethyl Silicone (PDMS) or hydroxyethyl methacrylate (HEMA), etc. The middle elastic dielectric layer 3 is composed of an elastic non-conductive film, and its material is also a biocompatible material, such as PDMS, elastic silicone (Ecoflex) or styrene-butadiene-styrene copolymer (SBS), etc. The film thickness is in the range of 20 to 50μm. The preparation process of the spiral inductor coil includes photolithography, electroplating, etching or sputtering, etc. The circuit line width ranges from 100 to 500μm and the thickness is 5 to 15μm. The inductance value of the toroidal inductor depends on the electrode thickness and the number of turns, usually 0 to 5μH; the capacitance value is related to the properties of the dielectric material and the electrode spacing, usually in the range of 0 to 25pF. In order to avoid affecting the wearer's vision, the distribution range of the middle elastic dielectric layer 3 and the spiral inductor coil is limited to a radius of 3.5 to 6.5mm from the center starting point of the contact lens.

[0064] Figure 1: is a schematic diagram of the structure layering of the contact lens type intraocular pressure sensor in the embodiment of the present invention. From bottom to top, it includes the second flexible packaging layer 11, the second spiral inductor 21, the middle elastic dielectric layer 3, the first spiral inductor 22, and the first flexible packaging layer 12; wherein, the second spiral inductor 21, the middle elastic dielectric layer 3, and the first spiral inductor 22 are located between the second flexible packaging layer 11 and the first flexible packaging layer 12; by opening a hole in the middle elastic dielectric layer 3, the electrical connection between the second spiral inductor 21 and the first spiral inductor 22 is achieved. Figure 2 Schematic diagram of the spiral inductor of the contact lens type intraocular pressure sensor in the embodiment of the present invention, wherein the second spiral inductor 21 and the first spiral inductor 22 are completely symmetrical in the plane. Figure 3 is an equivalent circuit diagram of the contact lens type intraocular pressure sensor in an embodiment of the present invention, describing the electrical characteristics of the inductor, capacitor and its resonant circuit.

[0065] Through trial production and verification, the intraocular pressure sensor of the present invention can realize the assembly of the capacitive pressure sensor only by folding the prepared circuit, successfully overcoming the problems of complex structure and difficult preparation of existing contact lens pressure sensors. The sensor structure and preparation process are simple, suitable for mass production of flexible circuits, significantly improving processing efficiency and reducing manufacturing costs.

[0066] The above content is a further detailed description of the present invention in conjunction with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, they can also make several substitutions or modifications to these described embodiments, and these substitutions or modifications should be regarded as belonging to the scope of protection of the present invention. In the description of this specification, the reference terms "one embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" refer to the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described are not necessarily the same as those of the embodiments. Materials or features may be used in any one or more embodiments or examples. In a suitable way. Without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications may be made herein without departing from the scope of protection of the patent application.

Claims

1. A wireless passive resonant sensor for intraocular pressure monitoring, characterized in that: include: A contact lens body, used to encapsulate the sensor assembly and serve as a substrate for the sensor; A first spiral inductor is disposed in the contact lens body; A middle elastic dielectric layer, covering the first spiral inductor to form a deformable dielectric; A second spiral inductor is disposed on the middle elastic dielectric layer, opposite to the first spiral inductor and forming an inductor component; The first spiral inductor, the middle elastic dielectric layer and the second spiral inductor together constitute a capacitor and equivalently form a series LCL resonant circuit, which responds to changes in intraocular pressure through changes in the resonant frequency of the resonant circuit.

2. The wireless passive resonant sensor for intraocular pressure monitoring according to claim 1, characterized in that: The contact lens body comprises a first flexible packaging layer and a second flexible packaging layer, and the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor are stacked and arranged between the first flexible packaging layer and the second flexible packaging layer.

3. The wireless passive resonant sensor for intraocular pressure monitoring according to claim 1, characterized in that: The first spiral inductor and the second spiral inductor are both made of flexible materials with a thickness in the range of 5-15 μm; the thickness of the middle elastic dielectric layer is in the range of 20-50 μm.

4. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 3, characterized in that: The first spiral inductor and the second spiral inductor have the same shape and are plane symmetrical; the center positions of the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor overlap with the contact lens body.

5. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 3, characterized in that: The contact lens body includes a central circular area covering the pupil and a peripheral area, and the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor are located in the peripheral area of ​​the contact lens body; preferably, the first spiral inductor, the middle elastic dielectric layer and the second spiral inductor are distributed between 3.5 and 6.5 mm from the center point of the contact lens.

6. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 3, characterized in that: The equivalent inductance value of the first spiral inductor and the second spiral inductor does not exceed 5H, and the capacitance value does not exceed 25pF.

7. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 3, characterized in that: The first spiral inductor and the second spiral inductor are made of patterned metal electrode materials. The current directions in the first spiral inductor and the second spiral inductor are opposite, namely clockwise and counterclockwise, respectively, forming a quasi-closed large coil system of current.

8. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 7, characterized in that: The first spiral inductor and the second spiral inductor are prepared into a symmetrical structure through planar micro-nano processing technology, and the capacitive intraocular pressure sensor is formed by folding the second spiral inductor above the first spiral inductor and sandwiching the middle elastic dielectric layer between the two.

9. The wireless passive resonant sensor for intraocular pressure monitoring according to any one of claims 1 to 8, characterized in that: The material of the contact lens body is selected from one or more of polyhydroxyethyl methacrylate (pHEMA), polydimethylsiloxane (PDMS), and hydroxyethyl methacrylate (HEMA), and the contact lens body is formed by hot pressing and heating of a mold; the middle elastic dielectric layer is composed of an elastic non-conductive film, and its material is a biocompatible material, selected from one or more of polydimethylsiloxane (PDMS), elastic silicone (Ecoflex), and styrene-butadiene-styrene copolymer (SBS).

10. A contact lens, characterized in that: A wireless passive resonant sensor for intraocular pressure monitoring as claimed in any one of claims 1 to 9.

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