JP2000079170A - Energy transmitting and/or information transmitting system to device for implantation into body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for supplying (transmitting) energy and/or transmitting information to a small device for implantation into a body such as a heat pacemaker without giving troubles to organic tissues and/or for receiving information obtained by the small device for implantation into the body outside the body. SOLUTION: Basically, a light-receiving element 4 is disposed within a living body, and is irradiated with near infrared laser beams. When energy is transmitted, the small device for implantation into a body is directly operated by electric energy photoelectrically converted by the light-receiving element, or a second battery is charged. When an information is transmitted, signals are sent to an information system of the small device by irradiating the laser beams modulated by the information. When the information is received, an information light from a luminous element provided within the body is detected by the light-receiving element 4 disposed outside the body. This system does not need a surgical operation for exchanging a first battery and special ways for obtaining the information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy transmission system and / or information transmission system for an implantable device. Here, the implantable device means an active type artificial heart, an artificial lung, an artificial pancreas, an artificial liver, and other organ replacements and power prostheses, exercise substitutes such as artificial legs, and a typical example of a cardiac pacemaker and the like. For example, small devices related to blood hemoglobin concentration monitor and insulin concentration monitor that monitor various states in the body are referred to as so-called microsensors of a type.

[0002]

2. Description of the Related Art Opportunities for using an implantable medical device are increasing as a method that does not rely on treatment using a surgical operation. Artificial hearts have been applied to humans after animal experiments, and cardiac pacemakers, which have developed mainly in the United States, are widely spread and are well known to people.

[0003] In order to operate such an implantable medical device independently in a body, a battery is used without exception except that the device is connected directly to a cable outside the body and driven directly.

[0004] Specifically, regarding a cardiac pacemaker, as for power supply to the pacemaker body, any one of a mercury battery, a lithium battery, and a nuclear battery is implanted in the body together with a device. The nuclear battery is 5
Able to supply high energy of 0 W or more and 30 to 4
Although adopted with the aim of a long service life of 0 years, there are problems with safety, and there are few application examples at present. In practice, it is generally designed to use a mercury battery or a lithium battery because it is safe and easy to apply.

[0005] However, these batteries (including nuclear batteries) have a limited life because they are primary batteries.
Mercury and lithium batteries have the problem of having to change batteries every 5 to 10 years, which forces patients to undergo surgical operations, which is physically and economically burdensome. .

[0006] In order to solve the above-mentioned problems in power energy supply, or in other small devices,
In order to pursue convenience (good portability), a wireless energy supply method has been proposed in which a battery is a secondary battery and energy is supplied from outside the body to the in-vivo secondary battery remotely. However, this method has a serious problem in that it generates strong electromagnetic waves due to the use of electromagnetic induction, which not only becomes a source of noise but also causes electromagnetic interference to equipment and living tissues. ing.

[0007] In contrast to the above-mentioned wireless energy supply, an outlet (connected to a small body device by a cable) is provided on the skin.
There is also a wired energy supply method in which the power is supplied directly from outside of the body, but this method is practically accepted in medical practice because it causes infection and inflammation at the skin penetration. Absent.

[0008] Another method of supplying energy to a secondary battery, which can be used safely and semi-permanently, is a method of utilizing bioenergy based on the concentration difference of living organisms, bioelectric current, muscle contraction force, and the like. However, the energy generated is at most 1
This method is impractical because it is as small as about 1 mV and about 1 V, so that it is out of the scope of research.

As described above, the problem of the life of the primary battery is considered to be two.
Even if you try to solve it with a secondary battery, the conceived conventional method has a big problem that exceeds its convenience,
Practical implementation is too difficult.

On the other hand, in addition to the problem of batteries, recently, with the progress of computerization, various biosensors have been developed, and the use of these sensors in bioimplantable devices has been attempted. Retrieves information about the state of the body through sensors, monitors the status of implanted devices, or gives commands to and controls devices (often with a built-in microchip such as a microcomputer) There is a growing need to send information from outside the body into the body for programming. Therefore, non-invasive to living tissue,
A need has arisen for a safe and accurate working method for transmitting and receiving information between external and internal small devices.

[0011]

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide an energy transmission system which does not impair a living tissue and which does not require replacement of a battery in an implantable device. Another object of the present invention is to provide an information transmission system capable of transmitting and / or receiving information between an extracorporeal device and an implantable device without causing any obstacle to living tissue. is there.
Still another object of the present invention is to provide a system that can sufficiently transmit energy or transmit and receive information even when the implantable device is installed deep inside the body. Still another object of the present invention is to provide an energy transmission system or information transmission / reception system in consideration of convenience and portability. It is another object of the present invention to integrate the energy transmission and the information transmission so as to construct the system as a simple form (to make it simple).

[0012]

In order to achieve the above object, an energy transmission system according to the present invention is electrically connected to a small device to be implanted in an animal body and a power supply system for driving the small device. A light-receiving element, and a near-infrared laser light projection optical system for projecting near-infrared laser light toward the light-receiving element, from outside the body of the animal, the light-receiving element of the small device embedded in the body of the animal A fundamental feature is that a near-infrared laser beam is projected toward the device and the small device can be driven with the electric energy photoelectrically converted by the light receiving element.

Further, the information transmission system for an implantable device according to the present invention comprises a small device to be implanted in an animal body and a light receiving element coupled to an information system for operating the small device and receiving information. A near-infrared laser light projection optical system for projecting near-infrared laser light carrying information toward the light-receiving element, from outside the body of the animal, to the light-receiving element of the small device embedded in the body of the animal A fundamental feature is that near-infrared laser light modulated by external information is projected toward the small device and the small device can be operated based on an electric signal photoelectrically converted by the light receiving element.

The information transmission system of the implantable device according to the present invention comprises a small device to be implanted in an animal body, a light emitting element coupled to an information system for operating the small device and information transmission, An information light detection system including a lens system that receives and condenses light from the light emitting element and a light receiving element that converts the condensed light into an electric signal,
By causing the light emitting element of the small device embedded in the body of an animal to emit light according to the information held by the small device, and converting the light emission into an electric signal by the light receiving element of the information light detection system, The basic feature is that various kinds of information as a result of the operation of the small device in the animal body can be taken out to the outside.

In the above-mentioned energy transmission system, near-infrared light has excellent transparency to living tissue, laser light has high energy efficiency, and near-infrared laser light has high energy supply efficiency. The power supply system includes a secondary battery, and the electric energy from the light receiving element charges the secondary battery. Therefore, the battery does not need to be replaced when the small device is continuously used. In addition, it does not prevent providing the primary battery in the power supply system of the small device.

In the above energy transmission system, the light receiving element should be buried as close to the body surface as possible for the efficiency of receiving the transmitted light energy. In such a case, the light receiving element is separated from the small device and placed near the body surface, and is connected to the small device by a conductor covered with a biocompatible film.

In the above energy transmission system, when the light projection optical system includes an optical fiber, the light projection optical system can be made to have a portable size, so that the animal in which the small equipment is embedded can freely move. . In other words, this means that animals (including humans, of course) are not placed in a predetermined place where the light projection optical system is kept stationary. Also,
Instead of emitting light directly from the tip of the optical fiber toward the light-receiving element, utilizing the small diameter of the cross section of the optical fiber (bundle) A fiber bundle having an outer diameter of about 0.5 mm is practically usable), and the tip of the optical fiber is positioned in the body of the animal by inserting a syringe needle or a catheter.
Light may be projected from the body to the light receiving element. By projecting light in this manner, energy efficiency can be improved exponentially.

According to the information transmission system for an implantable device that transmits information from outside the body to the inside of the body, an operation signal, a control signal, a data signal, and the like are freely transmitted from the outside of the body to the implanted device. In addition, the functionality of small devices can be significantly improved. The small device may be operated only when light is received by the light receiving element.
In other words, the small device is always inactive (does not function at all), and is activated only when a signal is given through the light receiving element.

According to the information transmission system in the implantable device for transmitting information from the inside of the body to the outside of the body, the small device embedded in the body, for example, various kinds of in-vivo information collected by the microsensor can be easily placed outside the body. Can be taken out,
By analyzing, analyzing, and using the extracted information, it is possible to contribute to medical and biological research, and at the same time, to treatment of animals including humans.

The above-mentioned light receiving element can be reduced in cost.
It is preferable to employ a sensor as sensitive as technically possible, for example, an avalanche photodiode or a PIN photodiode. On the other hand, a silicon photodiode or a solar cell can be used if the cost is reduced.

The most preferable form is to integrally construct an energy transmission and information transmission / reception system.
It is more preferable that the light receiving / light emitting element group inside and outside the body be modularized.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows the first embodiment, and a hatched portion represents a living tissue 1. A small implantable device 2 is embedded in a living tissue 1. On the body surface 3 side of the implantable device 2, a light receiving element 4 is provided fixed to the implantable device 2. The light receiving element 4 is electrically connected to a power supply circuit (not shown) for driving the implantable device 2. The power supply system includes a secondary battery that can be charged together with the primary battery. The light receiving element 4 is connected to a secondary battery via a predetermined circuit.

A near-infrared laser light projection optical system 6 having a near-infrared laser 5 is provided in a free space outside the skin 3 of the living body. The near-infrared laser light projection optical system 6 has a convex lens. 7, the near-infrared laser light 8 emitted from the near-infrared laser 5 is converted into parallel light 9.

The parallel light 9 from the near-infrared laser light projection optical system 6 is directed to the light receiving element 4 fixed to the implantable device 2.
To project. The near-infrared parallel light 9 passes through the epidermis 3, is scattered and absorbed in the living tissue 1, and the light receiving element 4 receives a fixed amount of the projected light amount. The light receiving element 4 performs photoelectric conversion of the received light to supply current to the circuit, and charges the connected secondary battery.

The secondary battery is used to assist the primary battery. The implantable device 2 always operates with a primary battery for safety, and when the power of the primary battery falls below a predetermined value,
Switch to secondary battery. In addition, it is good also as a structure which does not have a primary battery but only a secondary battery. At this time, when the power of the secondary battery is reduced or at an arbitrary time, the near-infrared laser light projection optical system 6 is operated to charge the secondary battery, and to continuously operate the implantable device 2. be able to. It should be noted that the implantable device 2 may be operated only when the secondary battery is charged.

The near-infrared laser 5 is selected as the light source because the living tissue 1 easily transmits near-infrared light. Also,
The output of the light source 5 is set so that the parallel light 9 has an energy density of 0.2 mW / cm ² or less, which is the maximum allowable exposure to the laser radiation of the skin 3.

The light receiving element 4 is selected to have a high sensitivity to the oscillation wavelength of the near-infrared laser 5. Generally, a photodiode is preferable, and a Si photodiode, PIN
Of photodiodes and avalanche photodiodes,
The latter two having high photoelectric conversion efficiency, that is, a PIN photodiode and an avalanche photodiode are particularly preferable. Further, a solar cell can be used, and the light receiving element mentioned here includes a solar cell. In terms of cost, solar cells are the cheapest. However, as shown in FIG. 2, the solar cell has lower photoelectric conversion efficiency than the Si photodiode. Since the photoelectric conversion efficiency is inferior, the light receiving element 4 using a solar cell must have a somewhat larger light receiving area.
However, it can be said that the application of the solar cell is very preferable in this point because the price is inexpensive which is incomparable with the cost of the PIN photodiode and the avalanche photodiode.

The body surface 3 on which the implantable device 2 is embedded
Is 5 to 10 mm.

FIG. 3 shows a second embodiment. FIG. 2 schematically shows a case where the implantable devices 21 and 22 are both installed inside the body and deeper than the body surface 31. The light receiving element 41 is located near the body surface 31, for example, D
= 10 mm. The light receiving element 41 is connected to the power supply system of the implantable device 21 via the conductive wire 23 and to the circuit system of the secondary battery provided inside.
The implantable device 22 is also connected to the same light receiving element 41 by the conductive wire 24.

Near-infrared laser 51, collimator lens 52
The near-infrared laser light projection optical system 60 including the condenser lens 53 projects the converged near-infrared laser light 91 toward the light receiving element 41. Similarly, the collected light is scattered and absorbed in the living tissue 11 to the same extent as the parallel light. However, since the light beam to be focused has directivity,
There is an advantage that positioning can be easily performed as a target of the light receiving element 11 and the light receiving surface of the light receiving element 11 can be reduced in diameter.

Of course, in the embodiment shown in FIG.
Is the maximum allowable exposure to laser radiation for
Irradiation is performed at an exposure amount of ² mW / cm ² or less.

The conductors 23, 24 are of course covered by a tube of a suitable biocompatible membrane. As a matter of course, the implantable devices 21 and 22 (similarly, the implantable device 2 in FIG. 1) are coated with a biocompatible film, and the living body 11 does not exhibit a foreign body rejection reaction.

FIG. 4 shows another embodiment. This embodiment is characterized in that an optical fiber 99 is used as compared with the above-described embodiment. The near-infrared laser 62 and the imaging lens 63 constitute the near-infrared laser light projection optical system 61 with the optical fiber bundle 99. Near infrared laser 62
Is imaged on one end face of the optical fiber 99 by the imaging lens 63, and near-infrared laser light enters here.
The optical fiber 99 guides the incident light, emits the light from the other end surface, and projects the emitted light toward the light receiving element 42 provided in the implantable device 25 embedded in the living tissue 12. The implantable device 25 includes a secondary battery (not shown), and the power energy photoelectrically converted by the light receiving element 42 can charge the secondary battery. Therefore, the implantable device 2
5 does not require any operation such as taking out the body by a surgical operation or the like and replacing the battery, and can continue to operate inside the body.

Preferably, the optical fiber 99 uses an optical fiber bundle having an outer diameter of 1 mm or less. An optical fiber bundle having an outer diameter of 0.5 mm and bundled with 10,000 or more single optical fibers is commercially available.
Such an optical fiber is used.

As in the embodiment shown in FIG. 4, by using the optical fiber 99 for the light projection, it is possible to provide an advantage that the flexibility of the optical fiber 99 can be utilized and the degree of freedom of the activity of the animal can be secured. . That is, the light source 6
For example, if a small one such as a laser diode is used for the light projection optical system 2, the light projection optical system 61 has an extremely compact configuration and the optical fiber 99 can be flexibly bent. Even if it is a human, even if it is worn at an appropriate place on clothes, for example, worn on a waist belt, light can be projected toward the light receiving element, so that animals and humans can freely act and act without being restricted by the device. Will be able to do it.

On the other hand, in the embodiment shown in FIGS. 1 and 2, if the laser light source 5 or 51 is a stationary laser, the operation of projecting the projection light 9 or 91 is performed on the living body 1 or the living body 1. 11 is bound at that time, and the charging operation becomes an act that can be performed only in a predetermined place. However, if the laser light source 5 or 51 is a small one such as a laser diode, the near-infrared laser light projection optical system 6, 60
Since is large enough to be held by hand, it can be considered that there is no great difference in convenience as compared with the embodiment of FIG.

FIG. 5 shows an example using an optical fiber.
In particular, a method is described in which, when the implantable device 25 is installed in a deep place below the skin 32, light projection can be performed more easily and more efficiently than in the configuration using the above-described conductor. FIG. 4A is provided for comparison with FIG. 4B, and is structurally equivalent to FIG.

In FIG. 5B, an injection needle or catheter 98 is inserted into the in-vivo device 26 embedded inside the living tissue 12, and the tip of the optical fiber 99 is inserted along the injection needle or catheter 98. Insert. Laser light emitted from the distal end surface of the optical fiber 99 is diffused in the living tissue 12 and is greatly absorbed and scattered in the living tissue 12, but if the light receiving surface of the light receiving element 42 is relatively large,
Almost all of the emitted light flux is received except for the amount absorbed. Therefore, this injection needle or catheter 9
The method using No. 8 is considered to be an excellent method that does not use a conductive wire (has high safety) and has high light receiving efficiency, although the living body is slightly damaged. Further, although it is somewhat difficult to fix the tip of the optical fiber 99 upright on the skin 32, the injection needle or the catheter 98 can be the upright fixing means.

Next, a verification example will be shown below to secure the effectiveness of each of the above embodiments. The verification example was performed using a cardiac pacemaker, which is a typical example of an implantable device, and it was confirmed that the pulse was correctly driven by light irradiation through a living tissue.

First, in order to examine how much light energy can be transmitted into a living body, near-infrared laser light was incident on a biological sample. As shown in FIG. 6, the optical system used includes a semiconductor laser 71 having a wavelength of 810 nm as a light source, a chicken 73 having a uniform thickness as a biological sample, a photodetector 74, and a computer 75 for acquiring data. The light emitted from the light source 71 is converted into parallel light having a beam diameter of 10 mm by the lens 72 and is incident on the biological sample 73. The photodetector 74 is brought into close contact with the back of the sample 73, and the light transmitted through the sample 73 is detected. By scanning the photodetector 74, the scattering distribution of the light transmitted through the biological sample 73 is measured. Further, the thickness of the biological sample 73 was changed from 5 mm to 30 mm in steps of 5 mm, and the light transmittance was examined.

FIG. 7 shows the spread of incident light due to a biological sample. The horizontal axis represents the distance from the optical axis center of the incident laser light, and the vertical axis represents the transmitted light intensity (mW / cm ² ) at each position.
Represents In order to determine the energy transmittance, each graph in FIG. 7 was fitted with a certain function f (x). t is the thickness of the biological sample, and x represents the position. The total power E (t) of the light transmitted through the living body is expressed by the following equation by integrating f (t, x) over the entire space. ^{_{E (t) = ∫ 0 ∞}} f (t, x) when the power of the 2πdx incident light is Ei, the transmittance of the energy η
(t) becomes η (t) = E (t) / Ei. FIG. 8 shows η (t) when the thickness of the biological sample was changed. It was found that when the thickness of the sample was 10 mm, η (t) = 38%. In addition, 80% of the energy transmitted through the living body is concentrated in a circular area within a radius of 15 mm.

In the preceding paragraph, how the light is transmitted in the living body has been described. Now, how much the transmitted light can be converted into electric energy will be evaluated. A summary of the types of light-receiving elements and energy conversion efficiency shows that silicon photodiodes and solar cells have high sensitivity in the near-infrared wavelength range.
It is about 0% and 10% (see FIG. 2).

As shown in FIG. 9, a light receiving surface of about 1000 mm ² is required in order to utilize the light energy transmitted through the biological sample as effectively as possible. Therefore, in this verification example, a solar cell which is inexpensive and can obtain a large area was used, and a solar cell array was created.

When the results of the first and second stages are combined, when the near-infrared laser is supplied as energy through the living body, the transmittance of the biological sample is about 40%, and the photoelectric conversion efficiency of the solar cell array used for verification is 10%. As a result, it was found that there was a total energy transfer efficiency of 4%.

Based on the above results, an experiment was conducted to drive an implantable device. The device used for the experiment was a cardiac pacemaker (manufactured by Nippon Medtronic Co., Ltd.). Two
Operating at 5V, the average power is 0.1 mW, the pulse rate is 65 ppm, and the minimum required incident light power to drive the pacemaker is 0.1 mW / 4% = 2.5 mW.

FIG. 10 shows the optical system used. Light source 71
6 is the same semiconductor laser as that of FIG. The thickness of the biological sample 73 is 10 mm. Biological sample 7
Behind 3, the created solar cell array 80 is placed, and the light passing through the living body 73 is converted into electric energy. The obtained electric power is guided to the pacemaker 81. Pacemaker 8
From 0, a resistor 82 of 500Ω equivalent to the impedance of a living body is connected to the electrode from which a pulse is generated.
The pulse waveform generated from the pulse electrode is converted to an oscilloscope 8
3 output.

FIG. 11 shows an output waveform from the oscilloscope. Vpp of pulse is 5V and pulse width is 0.5mse
c, The pulse interval was 920 msec. The average power that the solar cell is driving is 0.17 mW.
These facts demonstrate that each of the energy transmission systems described in the embodiments is effective for an implantable device.

FIG. 12 shows an illustration of an example in which the energy transmission system according to the present invention is applied to a cardiac pacemaker. A pacemaker body (not shown) is provided on the heart 85 of the patient 84, and the pacemaker body is controlled and driven by a control body 87 via a lead wire. A light receiving element 87 is fixedly provided on the control body 87 and is buried by surgery in a human body 84. From a near infrared laser 89 as a light source, an optical fiber 88
, The near infrared light is projected toward the light receiving element 87. The controller 86 of the pacemaker is provided with a secondary battery, and the photoelectric conversion power of the light receiving element 87 charges this secondary battery. Therefore, it is not necessary to perform a surgical operation for removing the battery as in the related art.

In the above description, the energy transmission has been described by way of the embodiment.
Light can be used in a manner similar to energy transmission.
At present, microsensors such as blood hemoglobin concentration monitor and insulin concentration monitor are under research and development.However, the information obtained by monitoring the state of the body collected by the microsensor of such an implantable device using light is used. And take it out of the body.

In the information transmission system, the light receiving element in the embodiment shown in FIGS. 1, 3, 4, and 5 is replaced with a light emitting element, and this light emitting element is used for an information system of an implantable device such as a microsensor. It is connected to a transmission unit and is constructed outside the body with a system provided with a lens system for condensing light emitted from the body surface and a photodetector. In this embodiment, the light source is replaced by a photodetector with the light traveling direction reversed in the embodiment shown in FIGS. 1, 3, 4, and 5. Since the information transmission system has a content that can be easily known to those skilled in the art only by showing its concept, a detailed description thereof will be omitted only by referring to the above embodiment.

A system for transmitting information from outside the body to the implantable device can also be constructed using light. In each of the embodiments shown in FIGS. 1, 3, 4 and 5, instead of the light receiving element coupled to the power supply system, a light receiving element for transmitting information is coupled to the information system of the implantable device, This is a system in which the light projected by the external laser light projection optical system is modulated (analog or digital modulation) according to external information and received by a light receiving element for receiving information. The information receiving system in this implantable device is also a content that can be easily known to those skilled in the art only by showing its concept. Omit.

In all of the above embodiments, the light source is
Although the near-infrared laser is used, it is not necessarily limited to a laser. In addition, because of good permeability to living tissue,
Although the near-infrared light is used, it is not necessarily limited to the use of the near-infrared light. Experiments using mice have shown that light in the visible range is better than near-infrared light.

[0052]

According to the energy transmission system for an implantable device according to the present invention, when the small device implanted in the body is continuously used without causing any obstacle to the living body, the primary battery must be replaced. This has the effect of eliminating the need for surgical operations.

According to the information transmission system of the present invention, there is an effect that no special treatment is required on the living body to remove the small device embedded in the body without causing any obstacle to the living body. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of a system according to the present invention.

FIG. 2 is a graph in which the photoelectric conversion efficiency of a Si photodiode and a solar cell is plotted.

FIG. 3 is an explanatory diagram of another embodiment of the system according to the present invention.

FIG. 4 is an explanatory diagram of still another embodiment of the system according to the present invention.

FIG. 5 is an explanatory diagram showing a specific use of the embodiment shown in FIG. 4 in comparison.

FIG. 6 is a diagram showing an optical system for verifying light irradiation on a living tissue.

FIG. 7 is a graph showing the spread of incident light obtained by changing the thickness.

FIG. 8 is a graph plotting energy transmittance with respect to thickness.

FIG. 9 is a graph plotting efficiency with respect to input power.

FIG. 10 is a configuration diagram of an optical system of a verification example.

FIG. 11 is an explanatory diagram of an output waveform obtained by adding specific numerical values to a waveform obtained by an oscilloscope.

FIG. 12 is an explanatory diagram in a case where the energy transmission system according to the present invention is applied to a cardiac pacemaker.

[Explanation of symbols]

 1, 11, 12 ... living tissue 2, 21, 22, 25, 26 ... implantable device 4, 41, 42, 87 ... light receiving element 5, 51, 62, 89 ... near infrared laser 99, 88 …… Optical fiber

Claims (15)

[Claims] A small device to be implanted in an animal body includes a light receiving element electrically connected to a power supply system for driving the small device, and projects near-infrared laser light toward the light receiving element. Providing a near-infrared laser light projection optical system, from outside the body of the animal, projected near-infrared laser light toward the light-receiving element of the small device embedded in the body of the animal, photoelectrically converted by the light-receiving element An energy transmission system for an implantable device, wherein the small device can be driven by electric energy. 2. The energy transmission for an implantable device according to claim 1, wherein the power supply system of the small device has a secondary battery, and the photoelectric conversion electric energy of the light receiving element charges the secondary battery. system. 3. The energy transmission system for an implantable device according to claim 1, wherein the light receiving element is fixed to the small device. 4. The energy transmission system for an implantable device according to claim 1, wherein the light receiving element is fixed near the body surface of the animal, and is connected to the small device by a conducting wire. 5. The energy transmission system for an implantable device according to claim 1, wherein the near-infrared laser light projection optical system includes an optical fiber. 6. A small device to be implanted in an animal body, comprising a light receiving element coupled to an information system for operating the small device and receiving information, and a near-infrared light carrying information toward the light receiving element. Providing a near-infrared laser light projection optical system for projecting laser light, from outside the body of the animal, the near-infrared laser light modulated by external information toward the light-receiving element of the small device embedded in the body of the animal An information transmission system for an implantable device, wherein the small device is made operable based on an electric signal that is projected and photoelectrically converted by the light receiving element. 7. The information transmission system for an implantable device according to claim 1, wherein the light receiving element is fixed to the small device. 8. The light receiving element is fixed near the body surface of an animal, and is connected to the small device by a conducting wire.
An energy transmission system for an implantable device according to claim 7. 9. The energy transmission system for an implantable device according to claim 6, wherein the near-infrared laser light projection optical system includes an optical fiber. 10. An energy transmission and information transmission system for an implantable device, wherein the light receiving element according to claim 1 and the light receiving element according to claim 6 are constituted by a single light receiving element. 11. A lens having a small device to be implanted in an animal body, a light emitting device coupled to an information system for operating the small device and transmitting information, and receiving and condensing light from the light emitting device. An information light detection system having a system and a light receiving element that converts the collected light into an electric signal is provided, and the light emitting element of the small device embedded in an animal body emits light in accordance with information held by the small device. The light receiving element of the information light detection system converts the light emission into an electric signal, thereby enabling various information as a result of the small device operating in an animal body to be taken out to the outside. Information transmission system for implantable devices. 12. The information transmission system according to claim 11, wherein the light emitting element is a light emitting diode that operates in a near infrared region. 13. The information transmission system according to claim 11, wherein the light-emitting element is a laser diode operating in a near-infrared region. 14. The information transmission system in an implantable device according to claim 11, wherein said light receiving element is one selected from a photomultiplier tube, an avalanche photodiode, and a PIN photodiode. . 15. An energy and information transmission system for an implantable device, comprising a combination of the energy transmission system according to claim 1, the information transmission system according to claim 6, and the information transmission system according to claim 11.