KR101581814B1

KR101581814B1 - Smart contact lens working in tear

Info

Publication number: KR101581814B1
Application number: KR1020140174392A
Authority: KR
Inventors: 박정열; 김정욱; 맹보희; 강동원
Original assignee: 서강대학교산학협력단
Priority date: 2014-12-05
Filing date: 2014-12-05
Publication date: 2016-01-04

Abstract

A smart contact lens is disclosed that can overcome the problems of energy sources for smart contact lenses. A smart contact lens comprising an optical component and an electronic component, the smart contact lens contacting the outer surface with oxygen on the cornea of the eye and facing the cornea on the inner surface, comprising an energy harvester for the electronic component, A first porous electrode film provided on the inner surface of the outer membrane, an ion selective membrane provided on the inner surface of the first porous electrode membrane, an ion-selective membrane provided on the inner surface of the first porous electrode membrane, A second porous electrode film provided on the inner surface of the second porous electrode film, and an inner film provided on the inner surface of the second porous electrode film and allowing glucose in the tear film to pass therethrough.

Description

[0001] SMART CONTACT LENS WORKING IN TEAR [0002]

The present invention relates to a smart contact lens, and more particularly, to an energy harvesting device capable of continuously supplying electric power from a smart contact lens using the environmental specificity of an eye.

As electronic devices have become smaller, body-worn or embeddable microelectronic devices have also been developed for a variety of applications. These microelectronic devices can be used for physical changes and adjustments of the body, chemical changes and adjustments, communication between the body and the outside, and improvement of the function of the body.

Examples of such devices include a glucose infusion pump, a pacemaker, a defibrillator, a ventricular assist device and a neurostimulator. In addition, new fields are lenses and contact lenses wearable for ophthalmology. For example, a wearable lens may include a lens assembly having an electronically adjustable focus to enhance or enhance the performance of the eye. In another example, the electronic contact lens may include an electronic sensor for detecting a specific change in the cornea.

With regard to electronic contact lenses, US Patent Application No. 61/564922 discloses an electronic contact lens for vision correction or other ophthalmic functions. The electronic contact lens includes an optical component and an electronic component that operate in conjunction with each other through an electrical and mechanical structure, and various circuits and components can be integrated into one structure to perform the desired function. As an example, an electronic contact lens can include a control circuit, a microprocessor, a communication device, a power supply, a sensor, an actuator, a light emitting diode, an optical sensor, an energy harvester and a small antenna.

In general, the components disposed within the lens must be miniaturized and integrated onto a transparent polymer of about 1.5 square centimeters while protecting the component from the liquid environment of the eye. In particular, since an electronic contact lens can not be supplied with power from the outside, an energy harvester capable of generating energy by itself is required, but a technique for specifying the energy harvester is not proposed.

Smart contact lenses are expected to provide not only augmented reality technology but also health monitoring through the eyes and ultimately therapeutic functions.

The researchers at the University of Washington in the United States first introduced a smart contact lens display technology for augmented reality, which integrates a single pixel LED element into a lens shape, and recently developed an 8 pixel device integration.

Google announced in January 2014 that it has developed a smart contact lens that can check blood glucose in real time through tears through the Google X project. By integrating Micro LED illumination into smart contact lenses, users can check blood glucose levels in real time .

The Swiss venture company Sensimed has developed 'Triggerfish', a contact lens type non-invasive medical device that can measure the intraocular pressure of patients with glaucoma in real time. 'Triggerfish' Measuring, transferring the measured data to the associated device, recording it, and storing it in the doctor's computer via Bluetooth. Therefore, it is expected to play a key role in diagnosing glaucoma and delaying the progress of glaucoma by monitoring in real time the intraocular pressure which is known to affect the progression of glaucoma.

Wireless RF technology is the only technology currently being adopted as an energy source for driving such a smart contact lens. Other energy sources including electric batteries are excluded due to limitations of flexibility and biocompatibility, limitations of service life, etc. Currently, wireless RF-based energy harvesting technology is used in terms of safety in terms of human body and energy transfer efficiency It is becoming a problem.

The present invention overcomes the problems of an energy source for a conventional smart contact lens. The present invention can be applied in a state where the eye is attached to the eye to continuously supply electric power, minimizes adverse effects on the body, And a smart contact lens including a hovering function.

Specifically, human tears contain not only various ions and proteins but also glucose, and since the tears of the corneal epithelium are exposed to the air at all times, it is noted that the optimal environment in which the oxidation of glucose occurs naturally in the human body A smart contact lens including an energy harvesting device based on glucose fuel cells capable of continuously supplying power to a smart contact lens by actively utilizing the environmental specificity of the human eye.

According to a preferred embodiment of the present invention, there is provided a smart contact lens including an optical component and an electronic component, wherein the smart contact lens, which is in contact with oxygen on the outer surface of the cornea of the eye and faces the cornea on the inner surface, And an energy harvester for electronic components, wherein the energy harvester comprises an outer membrane that passes oxygen but prevents passage of glucose in the tears, a first porous electrode membrane provided on the inner surface of the outer membrane, An ion selective membrane provided on the inner surface of the electrode membrane, a second porous electrode membrane provided on the inner surface of the ion selective membrane, and an inner membrane provided on the inner surface of the second porous electrode membrane and passing glucose in the tear film.

The energy harvester of the present invention utilizes the structural characteristics of the eye, that is, the feature that air is exposed only on one side of the contact lens when the contact lens is worn, thereby inducing a concentration gradient of glucose and oxygen on the inner and outer surfaces of the contact lens, And the like.

For reference, an electronic element in the present invention can be understood as a concept including a control circuit, a microprocessor, a communication device, a power supply, a sensor, an actuator, a light emitting diode, a light sensor, The present invention is not limited to or limited by the kind and characteristics of the material.

On the other hand, the porous electrode film must maintain mechanical stability against repetitive high bending deformation that occurs when the contact lens is worn off, and it is required to have a porous structure such that oxygen and glucose molecules can diffuse from the outside into the energy harvester . In the present invention, the porous electrode film lacking flexibility or elasticity can be deformed based on the matrix layer having relatively high flexibility and elasticity so that these conditions can be satisfied at the same time. For reference, it can be understood that, in the present invention, the porous electrode film is bent and deformed based on the matrix layer, and the porous electrode film can be bent and deformed by the bending and deformation characteristics of the matrix layer depending on the flexibility and elasticity of the matrix layer. More specifically, a matrix layer may be formed on at least one side of the first porous electrode film and the ion selective membrane, or between the second porous electrode film and the ion selective membrane, Hydrogels. &Lt; / RTI >

As the ion-selective membrane, various membranes having ion-selective properties depending on the required conditions and designs may be used. Preferably, the ion-selective membrane may be an ion-track etched polymer nanomembrane, and the ion-selective membrane comprising ion-track etched polymer nanomembranes may have a uniform size along the thickness direction (vertical direction) A plurality of pores may be provided through the porous structure.

The smart contact lens according to the present invention can be applied in a state of being mounted on an eye to continuously supply electric power to the smart contact lens, and can minimize the adverse effect on the body and maintain safety.

Particularly, according to the present invention, the environmental specificity of the human eye can be actively utilized to continuously supply power to the smart contact lens, so that safety in the human body can be improved and energy transfer efficiency can be improved.

On the other hand, a contact lens mounted on the eye of a human body can not be used as an energy source for a contact lens in the case of a battery formed using a hard material such as a silicon substrate because a high level of bending deformation occurs when the contact lens is worn. However, the energy harvester according to the present invention can be freely used as an energy source for a contact lens because it has flexibility, elasticity, and biocompatibility to prevent breakage or performance deterioration due to bending deformation.

Particularly, according to the present invention, each porous electrode film can have flexibility and elasticity, and as an ion-selective membrane, ion-track etched polymer having flexibility and elasticity and high ion selectivity, high conductivity and low fluid resistance ) Nanomembrane is used, it is possible to prevent breakage or performance deterioration due to bending deformation, and to improve the power density. As an example, the energy harvester according to the present invention can ensure a power density of at least 20 μW / cm 2.

Further, according to the present invention, since the porous electrode film can be bent and deformed based on the matrix layer made of hydrogel, it is possible to stably maintain the mechanical stability (restoring force due to repeated bending deformation, internal structure and surface change) have.

1 is a view for explaining a smart contact lens according to the present invention.
2 is a view for explaining an energy harvester as a smart contact lens according to the present invention.
3 is a view for explaining an ion selective membrane constituting an energy harvester as a smart contact lens according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments. For reference, the same numbers in this description refer to substantially the same elements and can be described with reference to the contents described in the other drawings under these rules, and the contents which are judged to be obvious to the person skilled in the art or repeated can be omitted.

FIG. 1 is a view for explaining a smart contact lens according to the present invention. FIG. 2 is a view for explaining an energy harvester 100 as a smart contact lens according to the present invention. 1 is a view for explaining an ion selective membrane constituting the energy harvester 100 as a lens.

Referring to FIG. 1, a smart contact lens 10 according to the present invention includes an energy harvester 100 for an electronic component, wherein the energy harvester 100 utilizes the environmental specificity of the human eye to provide a continuous And includes an outer membrane 110, a first porous electrode membrane 120, an ion selective membrane 130, a second porous electrode membrane 140, and an inner membrane 150.

For reference, the human eye is the only space in which body fluids (tears) are always in contact with the outside air, unlike other human organs. Human tears contain various ions and proteins as well as glucose at a concentration of 0.1-0.6 mM. Therefore, in the tears exposed to air, glucose is always oxidized by the enzyme.

The energy harvester 100 according to the present invention utilizes the structural characteristics of the eye, that is, the feature that the air is exposed only on one side of the contact lens when the contact lens is worn, thereby inducing a concentration gradient of glucose and oxygen on the inner and outer surfaces of the contact lens Thereby generating energy.

The smart contact lens 10 is provided including an optical component and an electronic component and can be used to face the cornea on the inner surface and oxygen on the outer surface on the cornea of the eye.

Further, the electronic element in the present invention may be understood as a concept including a control circuit, a microprocessor, a communication device, a power supply, a sensor, an actuator, a light emitting diode, an optical sensor, The present invention is not limited or limited depending on the kind and the characteristics.

The outer film 110 is disposed on the entire surface of the cornea of the eye such that the inner surface of the outer film 110 faces the entire surface of the cornea and the outer surface of the outer film contacts oxygen in the air. The outer film 110 may be formed of various materials having safety in the human body and capable of passing oxygen. For example, the outer layer 110 may be formed of PDMS (polydimethylsiloxane).

The first porous electrode film 120 is disposed on the inner surface of the outer film 110. For example, the first porous electrode layer 120 may be formed of activated carbon.

Meanwhile, the first porous electrode film 120 should be able to maintain mechanical stability against repetitive high bending deformation that occurs when the contact lens is worn off, and oxygen and glucose molecules may be injected from the outside into the energy harvester 100). &Lt; / RTI >

In the present invention, the first porous electrode film 120 (activated carbon), which is poor in flexibility or elasticity, is deformed based on the later-described matrix layers 160 and 170 having a relatively high flexibility and elasticity .

More specifically, a first matrix layer 160 may be provided between the first porous electrode layer 120 and an ion selective membrane 130 to be described later, and the first porous electrode layer 120 may include a first May be bend-deformed based on the matrix layer (160).

The bending deformation of the first porous electrode layer 120 on the basis of the first matrix layer 160 may be caused by the bending of the first matrix layer 160 due to the flexibility and elasticity of the first matrix layer 160, It can be understood that the first porous electrode film 120 can be bent and deformed by a deformation characteristic.

The first matrix layer 160 should have a porous structure capable of diffusing molecules and ions and be capable of maintaining a binding force with the ion selective membrane 130, which will be described later. Hereinafter, an example in which the first matrix layer 160 is formed of a hydrogel having a porous structure and capable of maintaining a high bonding force will be described.

The ion selective membrane 130 is provided on the inner surface of the first porous electrode film 120 so as to be disposed between the first porous electrode film 120 and the second porous electrode film 140 to be described later and has an ion selective characteristic . As the ion-selective membrane 130, various membranes having ion-selective characteristics may be used depending on the required conditions and designs. Preferably, the ion-selective membrane 130 may be an ion-track etched polymer nanomembrane, and the ion-selective membrane 130 made of the ion track-etched polymer nanomembrane may have a thickness direction The plurality of pores 132 having a uniform size may be provided through the porous structure.

As the ion selective membrane 130, a conventional ion selective membrane 130 used in conventional proton exchange membrane fuel cells (PEMFCs) may be used. However, existing ion-selective membranes have disadvantages in that ions and charges are trapped and the traveling length of the particles is relatively increased because internal tissues are complex and chaotic, In addition, the flow of medium (water), which has a decisive influence on the flow of the particles, is also disadvantageous in that it is subjected to a great resistance due to a complicated and disorderly structure.

However, according to the present invention, the ion track etch polymer nanomembrane used as the ion selective membrane 130 has a high ion selectivity ratio, and since the pores 132 are uniform in size and arranged in the vertical direction, The ion mobility is increased due to the short particle moving distance, and the conductivity can be improved. Further, the pore 132 has a relatively low fluid resistance as compared with the existing membrane through the vertical arrangement structure, and is flexible because it is a polymer-based structure.

Further, according to the present invention, ion track membrane polymer nanomembranes having flexibility, high ion selectivity, high conductivity and low fluid resistance are used as the ion selective membrane 130, so that the power density is further improved It is possible. In particular, the conventional glucose fuel cell has a problem that the output density is only a few μW / cm 2, which limits the application range. However, according to the present invention, by using the ion track etched polymer nanomembrane, a power density of at least 20 μW / It can be applied to a wide range of usage areas.

The second porous electrode film 140 is provided on the inner surface of the ion selective membrane 130. For example, the second porous electrode layer 140 may be platinum-based.

As with the first porous electrode film 120 described above, the second porous electrode film 140 should be capable of maintaining mechanical stability against repeated high bending deformation that occurs when the contact lens is worn away , The oxygen and glucose molecules have to have a porous structure so that they can diffuse from the outside into the energy harvester (100).

In the present invention, the second porous electrode film 140 (platinum), which is poor in flexibility or elasticity, can be deformed based on the second matrix layer 170 having a relatively high flexibility and elasticity Respectively.

More specifically, a second matrix layer 170 may be provided between the second porous electrode layer 140 and the ion selective membrane 130, and the second porous electrode layer 140 may be provided between the second matrix layer (170). &Lt; / RTI >

The second matrix layer 170 should have a porous structure capable of diffusing molecules and ions and be capable of maintaining a binding force with the ion selective membrane 130. Hereinafter, an example in which the second matrix layer 170 is formed of a hydrogel having a porous structure and capable of maintaining a high bonding force will be described.

In addition, the second porous electrode layer 140 and the first porous electrode layer 120 may be formed on the matrix layer using a conventional nanorod network structure and a three-dimensional inverse opal structure. have.

The inner film 150 is provided on the inner surface of the second porous electrode film and closely attached to a tear film formed on the entire surface of the cornea. The inner membrane 150 can pass glucose in the tears, and can be formed of various materials having safety in the human body. For example, the inner film 150 may be formed of PDMS (polydimethylsiloxane).

Owing to this structure, oxygen can be continuously introduced into the air through the first porous electrode film 120, while glucose can not be introduced into the air. Through the second porous electrode film 140, Glucose can be continuously introduced while oxygen can not be introduced. Therefore, in the first porous electrode film 120 and the second porous electrode film 140, a concentration gradient of glucose and oxygen may be generated. This concentration gradient can take electrons from glucose by using the first porous electrode film 120 and the second porous electrode film 140. In the process of producing water by transferring stray electrons to oxygen and hydrogen molecules, May occur.

Although the present invention has been described with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the following claims. It can be understood that

100: energy harvester 110: outer membrane
120: first porous electrode film 130: ion selective membrane
140: second porous electrode film 150: inner film
160: first matrix layer 170: second matrix layer

Claims

A smart contact lens comprising an optical component and an electronic component, wherein the contact lens is in contact with oxygen on the outer surface of the eye cornea and faces the inner surface with the cornea,
An energy harvester for said electronic component,
Wherein the energy harvester comprises:
Oxygen passes through the outer membrane which interferes with the passage of glucose in the tears;
A first porous electrode film provided on an inner surface of the outer film;
An ion selective membrane provided on the inner surface of the first porous electrode membrane;
A second porous electrode film provided on an inner surface of the ion selective membrane; And
And an inner film provided on the inner surface of the second porous electrode film and allowing glucose in the tear to pass therethrough.

The method according to claim 1,
Wherein the ion-selective membrane is an ion-track etched polymer nanomembrane.

3. The method of claim 2,
Wherein the ion selective membrane is provided with a porous structure in which a plurality of pores having a uniform size are penetrated in a thickness direction.

The method according to claim 1,
Wherein a matrix layer is formed on at least one side of the first porous electrode film and the ion selective membrane and between the second porous electrode film and the ion selective membrane.

5. The method of claim 4,
Wherein the matrix layer is formed of a hydrogel.

5. The method of claim 4,
Wherein the matrix layer is physically fixed to at least one of the first porous electrode film and the second porous electrode film,
Wherein the first porous electrode film and the second porous electrode film are bendable deformation based on the matrix layer.

The method according to claim 1,
Wherein at least one of the outer film and the inner film is formed of PDMS (polydimethylsiloxane).