JP2016126183A - Wearable device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact lens type wearable device having a stable power generation and storage function.SOLUTION: The wearable device includes; a pseudo eyelash which is formed of a magnetic material; and a contact lens. The contact lens includes: plural conductive lines which are radially disposed; and a thin film capacitor connected to the conductive lines. The thin film capacitor stores induction current which is generated on the conductive lines by blinking with the worn contact lens and the pseudo eyelash.SELECTED DRAWING: Figure 1

Description

  The present application relates to a wearable device capable of generating and storing electricity.

  A new market for wireless healthcare is emerging. For example, a business form is expected in which healthcare information is acquired using a wearable device and the information is stored in a cloud server to provide various healthcare services.

  Health log information can be acquired by a wearable device for use in self-health management, or a medical institution can be attached to a patient to acquire a bio log and determine medication timing. The wearable device can also be used as a tool for accurately providing care support in a nursing care situation. If biologs can be acquired more easily, more data will be stored in the cloud server and data analysis for medical and healthcare will proceed.

  By downsizing and making wearable healthcare terminals that have been large and bulky devices so far, portability is improved and biolog acquisition is simplified. Furthermore, by combining with a wireless communication transceiver, measurement and use management of measurement results can be performed in real time.

  As an example of a wearable device, a contact lens including a power generation / storage unit and a communication layer by photoelectric conversion (for example, refer to Patent Document 1) and a contact lens having a built-in antenna have been proposed (for example, Patent Document 2). reference). Also, a smart contact lens that incorporates a blood glucose sensor and wireless communication means to monitor blood glucose level by monitoring glucose contained in tears (see, for example, Non-Patent Document 1), Liquid crystal displays have been developed (see, for example, Non-Patent Document 2).

JP 2014-32316 A JP 2013-156632 A

http://japanese.engadget.com/2014.01.16.google-led/ http: /techtech.info/2013.08/.post086.html

  A contact lens type device incorporating a sensor, an antenna, a liquid crystal display, and the like can be manufactured by a semiconductor process or a MEMS (Micro Electro Mechanical Systems) process. However, there remains room for development regarding a power source for operating these functional elements. It is almost impossible to charge a contact lens type device using a power plug. Although it is conceivable to perform wireless power supply from the outside when not attached, a dedicated power supply device is required and is complicated. The power generation and storage structure by photoelectric conversion can be used only in the presence of light.

  Therefore, it is an object to provide a wearable device having stable power generation and power storage functions.

In one aspect, the wearable device is
Pseudo eyelashes made of magnetic material,
Contact lenses, wherein the contact lenses are
A plurality of conductive wires arranged radially; and
A thin film capacitor connected to the conductive wire,
The thin film capacitor stores an induced current generated in the conductive wire by blinking when the contact lens and the pseudo eyelashes are attached.

  A wearable device having stable power generation and storage functions is realized.

It is the schematic of the contact lens type wearable device of 1st Embodiment. It is a figure explaining the preparation methods of the contact lens of FIG. It is a figure which shows the example of mounting | wearing of the wearable device of 1st Embodiment. It is a figure which shows the electromotive force of the wearable device of FIG. It is a figure which shows the relationship between the data rate in various radio | wireless communication systems, and power consumption. It is a figure which shows the example of application to the sensor device of the wearable device of 1st Embodiment. It is a figure explaining the contact lens type wearable device of 2nd Embodiment. It is a figure explaining the effect of 2nd Embodiment. It is a figure explaining the effect of 2nd Embodiment. It is a figure which shows the example of application to the healthcare of the wearable device of embodiment. It is a figure which shows the example of application to the healthcare of the wearable device of embodiment.

<First Embodiment>
FIG. 1 is a diagram of a contact lens type wearable device 1 according to a first embodiment. Lithium ion batteries commonly used as hardware batteries are harmful to the human body and are not suitable for use in contact lens type wearable devices. Due to the nature of the contact lens type, a power generation and storage structure that is easy on the pupil and lens and has little effect on the field of view is desired.

  Since a capacitor has a small capacity as a storage battery, it has not been used in battery applications so far. However, a device with low power consumption can be operated by a capacitor that stores electric charge. Since a thin film capacitor uses a film-like or sheet-like dielectric, it is suitable for application to a thin device such as a lens.

  Therefore, in the embodiment, a power storage unit using a thin film capacitor is formed in the lens, and power generation and power storage are autonomously performed by electromagnetic induction using biological motion.

  FIG. 1A is a schematic diagram of the wearable device 1 of the embodiment, and FIG. 1B is an enlarged cross-sectional view of a region P in FIG. The wearable device 1 includes a contact lens 10 having a power generation and power storage function, and a magnetic body 35 that generates electromagnetic induction in the contact lens 10. The contact lens 10 is formed with a plurality of conductive lines 12a and 12b in a radial pattern except for the central portion. As the magnetic body 35 moves in the direction of arrow M above the contact lens 10 and crosses the conductive lines 12a and 12b, an induced current flows through the conductive lines 12a and 12b. In FIG. 1A, a conductive line 12 a is formed in the central region excluding the central portion of the contact lens 10, and a conductive line 12 b is formed in the peripheral region of the contact lens 10. This is to give the appearance that there is no sense of incongruity when the contact lens 10 is worn, and the conductive wires 12a and 12b may be formed as a single continuous wire. Since the central portion of the contact lens 10 corresponds to the pupil, it is desirable not to arrange the conductive lines 12a and 12b.

The contact lens 10 has a built-in thin film capacitor 20, and when current flows through the conductive wires 12 a and 12 b due to electromagnetic induction caused by the movement of the magnetic body 35, charges are accumulated in the thin film capacitor 20. The thin film capacitor 20 includes a dielectric film 11 and electrode films 13 a and 13 b formed on the upper and lower surfaces of the dielectric film 11. The dielectric film 11 is a high dielectric film that also serves as a lens, for example. The electrode films 13a and 13b are thin films of metal having transparency to visible light, such as Ti (titanium), Au (gold), Ag (silver), Pt (platinum), and Cu (copper). It is about 3 to 15 nm.

  The conductive lines 12a and 12b are formed on the thin film capacitor 20 via an interlayer insulating film (not shown), and are electrically connected to the electrode film 13a or 13b of the thin film capacitor 20 through contact vias or the like. The conductive wires 12a and 12b are formed of Al (aluminum), Ti, Au, Cu, Ta (tantalum), Ni (nickel), etc., and the eddy current is sufficiently generated inside by the movement of the magnetic body 35 (change in magnetic field). It has a thickness that can be generated. Depending on the color of the pupil, the surface of the Al conductive lines 12a and 12b can be coated with Ti, Au, Ta, etc., and the nitrided film can be formed by adjusting the nitriding rate. is there. Although not shown, a rectifier circuit is formed on the outer periphery of the contact lens 10 or on a layer different from the thin film capacitor 20 and the conductive wires 12a and 12b, and the eddy current generated in the conductive wires 12a and 12b is rectified to a direct current. To do.

  The thin film capacitor 20 and the conductive wires 12 a and 12 b may be covered with the lens layer 15. The lens layer 15 is formed of a resin film or silicon having a hydrophilic property and high light transmittance, such as an acrylic resin. When a resin film is used as the lens layer 15, an element layer including the thin film capacitor 20 and the conductive wires 12 a and 12 b is formed in advance by a semiconductor process or the like, and a pair of lens layers 15 formed into a predetermined contact lens shape is formed. The element layer may be sandwiched.

  When the dielectric film 11 of the thin film capacitor 20 is used as a contact lens without using the lens layer 15, as shown in FIG. 2, the dielectric films 115a and 115b having different curing shrinkage rates are alternately arranged radially. The electrode films 13a and 13b, the conductive lines 12a and 12b, an interlayer insulating film (not shown), contact vias, and the like are formed at a temperature of 180 ° C. or lower, and heat treatment is performed at 250 ° C. The dielectric films 115a and 115b having different curing shrinkage rates are deformed into spherical shapes due to the difference in shrinkage rates. By selecting the curing shrinkage rate, the curvature of the spherical surface can be set to a desired value.

  FIG. 3 shows an example of wearing the wearable device 1. In the embodiment, the magnetic body 35 that causes electromagnetic induction is realized by the pseudo eyelashes 30. The pseudo eyelash 30 has an arcuate mounting portion 32 and a magnetic eyelash 31 extending from the mounting portion 32. The magnetic eyelashes 31 are formed of a high magnetic material obtained by bonding magnetic powder or nanomagnetic particles with an epoxy resin or the like.

  When the wearer of the contact lens 10 blinks, the magnetic eyelashes 31 move in the direction of the arrow at a speed v. When the magnetic eyelash 31 crosses the conductive wire 12 (see FIG. 1) formed on the contact lens 10, an induced current flows in a direction perpendicular to the magnetic field due to a change in magnetic flux in the conductive wire 12. An alternating current flows through the conductive wire 12 due to the reciprocating motion of the magnetic eyelashes 31 caused by blinking, and the rectified charge is accumulated in the thin film capacitor 20.

  Here, the electromotive force P caused by blinking is expressed by the following equation.

式（１）は、瞬き１回（１サイクル）当たりの起電力ｐ[w]を表わす。式（１）において、ｎは磁性体まつ毛３１が通過する導電線１２の本数、ｃは誘導電流効率係数、ΔΦは磁束変化量[Wb]、Δｔは瞬き１サイクルの時間、すなわち磁性体まつ毛３１の移動時間[s]、Ｂは磁束密度[T]、ｌは磁束が横切る距離（この例では導電線１２の長さ）[m]、ｖは磁束が導電線１２を横切る速度[m/s]、Ｒは導電線１２の配線抵抗[Ω]である。

Equation (1) represents the electromotive force p [w] per blink (one cycle). In equation (1), n is the number of conductive wires 12 through which the magnetic eyelashes 31 pass, c is the induction current efficiency coefficient, ΔΦ is the amount of change in magnetic flux [Wb], Δt is the time of one blink, ie, the magnetic eyelashes 31. Travel time [s], B is the magnetic flux density [T], l is the distance traversed by the magnetic flux (in this example, the length of the conductive wire 12) [m], v is the velocity of the magnetic flux traversing the conductive wire 12 [m / s] ], R is the wiring resistance [Ω] of the conductive wire 12.

The magnetic flux change amount ΔΦ is expressed by Expression (2), and the wiring resistance R is expressed by Expression (3). In equation (3), ρ is resistivity [Ωm], and A is wiring cross-sectional area [m ² ].

  If the number of blinks per minute is f, the electromotive force P [Wh] is expressed by equation (4). In order to improve the electromotive force P, the magnetic eyelashes 31 are preferably made of a material having a high magnetic flux density. In addition, it is desirable to increase the number of conductive wires 12 traversed by the magnetic eyelashes 31 and decrease the resistance.

  The electromotive force P is proportional to the number of blinks f. The number of blinks f is approximately 20 times / minute for adult men, 15 times / minute for adult women, and 10 times / minute for children, and it is not expected to increase the number of blinks in order to increase the amount of magnetic flux change ΔΦ. . Further, the size of the contact lens 10 is about 10 mm in diameter, and it is difficult to increase the distance l in order to increase the magnetic flux change amount ΔΦ. Therefore, it is desirable to reduce the wiring resistance of the conductive wire 12 and increase the dielectric current efficiency c.

  FIG. 4 is a graph illustrating the electromotive force of the wearable device 1 of the embodiment. On the contact lens 10, 157 Cu wirings having a length (l) of 5 mm, a width (W) of 100 μm, and a thickness (T) of 1 μm are formed radially as the conductive wires 12. The wiring resistance per one conductive wire 12 is 1Ω. As a magnetic body 35 (see FIG. 1) for the experiment, a ferrite magnet having a magnetic flux density of 0.18T, an Al-Ni-Co magnet having a magnetic flux density of 0.25T, and a neodymium magnet having a magnetic flux density of 0.5T. Use. The blinking speed, that is, the moving speed v of the magnetic body 35 is set to 100 m / s. Assuming children and adult men and women, the number of blinks is 10 / min, 15 / min, and 20 / min.

  When the alnico magnet is used, the induced current is 44 μAh to 88 μAh. When a neodymium magnet is used, the induced current is 1.8 mAh to 3.5 mAh. The induced current efficiency at this time is about 30%.

  FIG. 5 is a graph showing the relationship between data rate (Mbps) and power consumption (mW) according to various communication standards. When an antenna circuit is formed on the contact lens 10 of the wearable device 1 to provide a communication function, it is desirable that transmission can be performed with less power consumption. Unless a high transmission rate is required, communication with low power consumption is possible using a communication standard such as BTLE (Bluetooth Low Energy) or ZigBee (registered trademark). For example, low power consumption communication of 0.1 mW to 0.5 mW is possible at a data rate of 10 kbps.

  Returning to FIG. 4, considering communication per hour, in the case of the BTLE standard, communication of an average of 20 kbps is possible for an alnico magnet, and communication of an average of 60 kbps is possible for a neodymium magnet.

  FIG. 6 shows a modification in which the wearable device 1 has an antenna function. 6A, in addition to the storage element (thin film capacitor) 20 and the induction circuit (conductive wire) 12, a control circuit 41, an antenna 42, a sensor 43, and a memory circuit 44 are formed. Has been. The wearable sensor device 1 </ b> A is configured by combining the contact lens 10 and the magnetic eyelashes 31.

  The control circuit 41, the antenna 42, the sensor 43, and the memory circuit 44 can be formed using a semiconductor process in a layer different from the layer in which the thin film capacitor 20 or the conductive wire 12 is formed, or in a different region of the same layer. For example, the sensor 43 may be formed on the concave surface side of the contact lens 10A, and the antenna 42 may be formed in the outer peripheral region of the contact lens 10A where the conductive wire 12 is not formed. The sensor 43 measures the secretion dynamics of tears, the glucose (glucose) concentration in blood components contained in tears, and the like. The measurement result is stored in the storage circuit 44 by the control circuit 41. The control circuit 41 transmits the stored measurement result from the antenna 42 to the external device at a predetermined timing.

  When the contact lens type wearable sensor device 1A is provided with a communication function, short-distance communication with low power consumption is preferable. Therefore, an external device having a wireless function may be incorporated in glasses, headphones, earrings, bandanas, watches, and the like, and the measurement result by the sensor 4 may be acquired as a biological log.

  The control circuit 41, the antenna 42, the sensor 43, and the memory circuit 44 operate with electric power stored in the storage element (thin film capacitor) 20 by blinking. As described with reference to FIGS. 4 and 5, when the measurement result by the sensor 43 is transmitted to an external device, the amount of data is not so large and high-speed communication is not necessary. Measurement data can be wirelessly transmitted to an external device with electric power generated using pseudo eyelashes 30 having a permeability equivalent to that of an alnico magnet.

In addition to the power storage element (thin film capacitor) 20 and the induction circuit (conductive wire) 12, a control circuit 41 and an antenna 42 are formed on the contact lens 10B of FIG. The configuration in FIG. 6B does not have a sensor, but a signal is transmitted when a blink is performed a predetermined number of times and a certain amount of charge is accumulated. That is, the fact that a predetermined number of blinks has been performed is transmitted as sensor information. The control circuit 41 transmits a signal from the antenna 42 to the external device when a certain induced electromotive force is obtained. By looking at the timing of signal reception with an external device, blink frequency information can be acquired. As will be described later, the number of blinks can be used as a biological log for health care analysis.
Second Embodiment
The wearable device 2 according to the second embodiment will be described with reference to FIGS. FIG. 7 is a schematic diagram of a contact lens 50 used in the wearable device 2 of the second embodiment. The contact lens 50 has a plurality of conductive lines 52 formed radially. Each conductive line 52 is formed in a zigzag pattern, and the length of the conductive line 52 along the radial direction of the contact lens 50 is defined as l. It is desirable that the conductive line 52 has as little a component as possible with respect to the moving direction M of the magnetic body 35, and is formed in a sawtooth or triangular wave shape. In the example of FIG. 7B, a sawtooth wiring that bends at an angle of 60 ° is used.

  The configuration of FIG. 7 can improve the induction current efficiency as compared with the wiring shape of the first embodiment shown in FIG. In the contact lens 10 of FIG. 8, the linear conductive wires 12 are arranged radially, and no induced current flows through the conductive wires 12 extending at an angle parallel or nearly parallel to the moving direction (that is, the blinking direction) M of the magnetic flux. The region R of the conductive wire 12 that intersects the moving direction M of the magnetic flux at right angles or at an angle close to 90 ° contributes to the generation of electromotive force.

  On the other hand, in FIG. 8, each conductive wire 52 has a zigzag shape and is arranged radially. Even when the direction of the length l of the conductive wire 52 is parallel to the moving direction M of the magnetic flux, the wiring component 52a intersects with the moving direction of the magnetic flux. Therefore, the region R that contributes to the generation of the electromotive force can be secured over the entire circumference of the contact lens 50.

  7B, the conductive line 52 has a wiring component 52b extending at an angle of 30 ° with respect to the radial direction of the contact lens 50 and a wiring component 52a bent at an angle of 60 ° with respect to the wiring component 52. N bends. If the length of the conductive line 52 along the radial direction of the contact lens 50 is 1, the length of one peak is 1 / n, and the length of the wiring component 52a is 1 / √3n, which is approximately 1 / 2n. . The conductive line 52 contributes to the electromotive force approximately half of the length l (n × l / 2n), and an electromotive force corresponding to this is generated. Further, when the magnetic flux reciprocates in the direction perpendicular to the longitudinal direction of the conductive wire 12, an electromotive force corresponding to 1 / n is generated. The induced current efficiency in theoretical calculation is 80%.

  FIG. 9 is a diagram illustrating the effect of the configuration of the second embodiment. A zigzag conductive line 52 having a width (W) of 100 μm, a thickness (T) of 1 μm, and a radial length 1 of the contact lens 50 of 5 mm is formed on the contact lens 50 under the same conditions as in the first embodiment. Then, the magnetic body 35 is moved at a speed (v) of 100 m / s. The simulation result of the contact lens 10 of the first embodiment is shown as Case 1 (“Case 1”), and the simulation result of the contact lens 50 of the second embodiment is shown as Case 2 (“Case 2”).

  Comparing the electromotive force when the number of blinks is 15 times / minute, the case 2 uses a neodymium magnet having a magnetic flux density of 0.5T as the magnetic body 35 and an alnico magnet having a magnetic flux density of 0.25T. The electromotive force is improved to 3.75 times the electromotive force of Case 1. When an alnico magnet is used, the communication rate is improved from 20 kbps to 300 kbps.

The wearable device 2 using the contact lens 50 of the second embodiment can be extended to a wearable sensor device as shown in FIG. In this case, since the power generation and power storage efficiency is improved, the frequency of measurement by the sensor 43 and the frequency of transmission from the antenna 42 can be increased.
<Application example>
10 and 11 show an application example of the wearable device of the embodiment to healthcare. FIG. 10 is an example of biological information analysis based on the signal frequency from the wearable sensor device 1B of FIG. In FIG. 10, a signal is acquired from the wearable sensor device 1B every time the amount of electricity stored in the thin film capacitor 20 exceeds a predetermined amount. Since the induced current generated per blink is substantially the same, it is transmitted every time the blink is performed a predetermined number of times. In the example of FIG. 10, an induced power of 7.8 μW is obtained in one blink, and one transmission is performed when it exceeds 40 μW. When signal transmission is performed at a communication rate of 1 kbps with ZigBee (registered trademark), a signal is transmitted from the wearable sensor device 1B every five blinks as indicated by an arrow.

  It has been reported that the timing at which a living body blinks varies depending on gender and health status. When the normal state and the tension state are compared, the number of blinks is large in the case of the tension state. By analyzing the blink frequency, the psychological state can be measured in real time. In FIG. 10, a section where the signal transmission timing is early indicates a tension state, and a section where the transmission timing is late indicates a relaxed state. For example, when the average transmission interval is shorter than 25 seconds, it can be considered that the wearer of wearable device 1B is in a tension state. By using this system, it is possible to grasp the mental state almost in real time and use it for health care.

  FIG. 11 is a graph displaying the frequency of blinks over a long period of time. This graph is created based on a signal transmitted from the wearable device 1B every predetermined number of blinks as in FIG. By displaying the graph in the long term, the mental state of the wearer and the sleep state can be grasped visually and directly.

  Information obtained from the wearable devices 1, 1 </ b> A, 1 </ b> B, and 2 of the embodiment can also be used for dry eye prevention, tension relaxation, and doze prevention. The configuration of the contact lenses 10 and 50 used in the wearable device can also be applied to an active lens device with a power source. For example, a contact lens 50 that can switch between an ultraviolet (UV) cut mode and a clear mode may be realized by incorporating an element that changes color according to voltage and a voltage control circuit in the contact lenses 10 and 50.

1, 1A, 1B, 2 Wearable device 10, 10A, 10B, 50 Contact lens 11 Dielectric film 12, 52 Conductive wire 13a, 13b Electrode film 15 Lens layer 20 Thin film capacitor 30 Pseudo eyelash 31 Magnetic eyelash 32 Mounting part 35 Magnetic Body 41 Control circuit 42 Antenna 43 Sensor 44 Memory circuit

Claims (9)

Pseudo eyelashes made of magnetic material,
Contact lenses, wherein the contact lenses are
A plurality of conductive wires arranged radially; and
A thin film capacitor connected to the conductive wire,
The wearable device, wherein the thin film capacitor stores an induced current generated in the conductive wire by blinking when the contact lens and the pseudo eyelashes are attached.   The wearable device according to claim 1, wherein the conductive line is a linear wiring arranged radially except for a central region of the contact lens.   The wearable device according to claim 1, wherein the conductive lines are zigzag wirings arranged radially except for a central region of the contact lens.   The wearable device according to claim 1, wherein the contact lens includes a lens layer that covers the thin film capacitor and the conductive wire.   2. The thin film capacitor includes a dielectric film and a pair of light transmissive electrode films sandwiching the dielectric film in a film thickness direction, and the dielectric film also serves as a lens layer. Wearable device according to. The contact lens has a control circuit and an antenna connected to the thin film capacitor,
The wearable device according to claim 1, wherein the control circuit transmits a signal from the antenna when a certain amount of electric charge is accumulated in the thin film capacitor. The contact lens has a control circuit connected to the thin film capacitor, a sensor, a memory circuit, and an antenna,
The storage circuit holds information measured by the sensor,
The wearable device according to claim 1, wherein the control circuit transmits the information from the antenna at a predetermined timing.   The contact lens used with the wearable device of Claims 1-7. The false eyelashes used in the wearable device according to claim 1,
Arc-shaped mounting part;
Magnetic lashes extending from the mounting portion;
Having false eyelashes.

Images