JP2017163636A - Energy transmitter, energy receiver, energy transmitter receiver, and wireless power supply system with them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transport an energy ensuring a safety property for eyes.SOLUTION: An energy transmitter comprises: a laser irradiation device that irradiates a plurality of laser beams of which an optical axis is different; and an irradiation direction control device that controls an irradiation direction of the plurality of laser beams. The irradiation direction control device allows the optical axis of the plurality of laser beams at one point. An energy receiver comprises: a photoelectric conversion device that converts the laser beam incident from a reception surface to an electric energy; a laser beam strength measurement device that measures a light strength of the laser beam incident to the reception surface; and an adjustment device that adjusts a relevant position relationship of the optical axis of the laser beam and the reception surface of the photoelectric conversion device so that light strength of the laser beam incident to the reception surface is increased.SELECTED DRAWING: Figure 1

Description

  The technology disclosed in the present specification relates to an energy transmission device, an energy reception device, an energy transmission / reception device, and a wireless power feeding system including these.

  Laser light with high energy density and excellent directivity is required in various situations, and is expected to be used for wireless communication and wireless power feeding, for example. Patent Document 1 discloses a system in which laser light is supplied to a moving body including a receiving unit that converts laser light into electric power by a supply unit that converts a power source into laser light.

JP 2010-166675 A

  Laser light having a high energy density is known to have various adverse effects on the eye. In the system of Patent Document 1, even if it is desired to increase the energy density of the laser light from each supply means, the danger to the eyes must be taken into account, and as a result, large energy cannot be supplied. The present specification discloses an energy transmission device, an energy reception device, an energy transmission / reception device, and a wireless power feeding system including the energy transmission device, energy reception device, and energy transmission device that can transport large energy while ensuring safety for eyes.

  The present specification discloses an energy transmission device and an energy reception device. The energy transmission device and the energy reception device disclosed in the present specification may be used alone or may be used as an energy transmission / reception device using both at the same time.

  The energy transmission device includes a laser irradiation device that irradiates a plurality of laser beams, and an irradiation direction control device that controls the irradiation directions of the plurality of laser beams. The irradiation direction control device crosses the optical axes of a plurality of laser beams at one point.

  The above energy transmission device crosses a plurality of laser beams at one point by the irradiation direction control device. When a plurality of laser beams are collected at one point, all the energy of the plurality of laser beams is concentrated at that point. Therefore, large energy can be transmitted by receiving laser light at this point. Further, since the laser light can be divided and irradiated, the energy of each laser light can be reduced. For this reason, the safety | security with respect to eyes can be ensured.

  The energy receiving device includes a photoelectric conversion device that converts laser light incident on the receiving surface into electrical energy, a light intensity measuring device that measures the light intensity of the laser light incident on the receiving surface, and a laser light incident on the receiving surface. A position adjusting device for adjusting a relative positional relationship between the optical axis of the laser beam and the receiving surface of the photoelectric conversion device so that the light intensity increases;

  In the energy receiving device, the light intensity measuring device measures the light intensity of the laser light incident on the receiving surface. The position adjusting device adjusts the relative position between the optical axis of the laser beam and the receiving surface so that the light intensity increases based on the measurement result. Therefore, the laser beam can be received at a position where the light intensity of the laser beam is higher. For this reason, energy can be received efficiently.

  The present specification also discloses a wireless power feeding system including the energy transmitting device and / or the energy receiving device.

1 is a diagram schematically illustrating a configuration of a wireless power feeding system according to a first embodiment. The enlarged view of the receiving surface of the energy receiver of Example 1. FIG. The figure which shows typically the structure of the wireless electric power feeding system of Example 2. FIG. The top view which shows typically the structure of the irradiation direction control apparatus of the energy transmission apparatus of Example 3. FIG. Sectional drawing along the VV line | wire of FIG. FIG. 10 is a diagram illustrating an operation of the energy transmission device according to the third embodiment. The figure which shows the modification of the energy transmitter of Example 3 (corresponding to FIG. 6). The figure which shows the modification of the energy transmitter of Example 3 (corresponding to FIG. 6).

  The features of the technology disclosed in this specification will be summarized below. The items described below have technical usefulness independently.

  The energy transmission device disclosed in the present specification may include a laser irradiation device that irradiates a plurality of laser beams and an irradiation direction control device that controls the irradiation directions of the plurality of laser beams. The irradiation direction control device crosses the optical axes of a plurality of laser beams at one point. The irradiation direction control device may be configured to be movable at a position where the optical axes of a plurality of laser beams intersect. According to such a structure, the distance which a some laser beam condenses can be adjusted. The irradiation direction control device may be configured to be movable at a position where the optical axes of the plurality of laser beams intersect based on the position of the receiving device that receives energy from the plurality of laser beams. According to such a configuration, it is possible to suitably irradiate the receiving apparatus with laser light. Each of the plurality of laser beams may have a wavelength of 1200 nm or more and 1400 nm or less. According to such a configuration, the danger to the eyes can be reduced. The laser irradiation apparatus has a plurality of laser light sources, and the laser light irradiated from each of the plurality of laser light sources may correspond to each of the plurality of laser lights, or irradiation from one laser light source. The laser beam may be branched and irradiated with a plurality of laser beams.

  An energy receiving device disclosed in this specification includes a photoelectric conversion device that converts laser light incident on a receiving surface into electrical energy, a light intensity measuring device that measures the light intensity of laser light incident on the receiving surface, and a receiving surface. There may be provided a position adjusting device that adjusts the relative positional relationship between the optical axis of the laser light and the receiving surface of the photoelectric conversion device so that the light intensity of the laser light incident on the light source increases. The light intensity measuring device may be configured to measure a light intensity distribution in the receiving surface of the laser light incident on the receiving surface of the photoelectric conversion device. The position adjusting device may adjust the relative positional relationship between the optical axis of the laser light and the receiving surface of the photoelectric conversion device based on the light intensity distribution of the laser light. The position adjustment device identifies the peak position of the laser light intensity based on the light intensity distribution of the laser light, and adjusts the optical axis of the laser light and the photoelectric conversion device so that the center position of the receiving surface approaches the peak position. You may adjust the relative positional relationship of a receiving surface. According to such a configuration, the energy of the laser beam can be received efficiently. In addition, the photoelectric conversion device may include a photodiode array including a plurality of photodiodes. According to such a configuration, it is possible to improve the conversion efficiency of received laser light into energy. Moreover, you may further provide the position specific apparatus which specifies the present position of the receiving surface of a photoelectric conversion apparatus. The position adjusting device may adjust the relative positional relationship between the optical axis of the laser beam and the receiving surface of the photoelectric conversion device based on the current position of the receiving surface of the photoelectric conversion device. According to such a configuration, the laser beam can be received stably.

  In the energy transmission / reception apparatus disclosed in this specification, the laser irradiation apparatus of the energy transmission apparatus may be configured to modulate a plurality of laser beams corresponding to transmission data. Moreover, the photoelectric conversion device of the energy receiving device may be configured to demodulate transmission data from the received laser light. According to such a configuration, data communication can be made possible.

  A wireless power feeding system 1A according to a first embodiment will be described with reference to the drawings. As shown in FIG. 1, the wireless power feeding system 1A includes an energy transmission device 2 (hereinafter referred to as a transmission device 2) and an energy reception device 3 (hereinafter referred to as a reception device 3).

  The transmission device 2 includes a laser irradiation device 4 and an irradiation direction control device 6. The laser irradiation device 4 has a plurality of laser light sources 7 and is configured to irradiate a plurality of laser beams parallel to each other. The wavelength of the laser light emitted from each of the plurality of laser light sources 7 is, for example, in the range of 1200 nm to 1400 nm. Further, the intensity of the laser light emitted from each of the plurality of laser light sources 7 is set to 16 mW or less.

  The irradiation direction control device 6 controls the irradiation direction of the laser light emitted from each of the plurality of laser light sources 7. In this embodiment, a variable focus lens is used for the irradiation direction control device 6. The variable focus lens of the irradiation direction control device 6 is disposed at a position where the laser light emitted from each of the plurality of laser light sources 7 is transmitted. Laser light emitted from each of the plurality of laser light sources 7 enters the variable focus lens of the irradiation direction control device 6. The variable focus lens of the irradiation direction control device 6 is configured to condense each of the irradiated laser beams and to cross their optical axes at one point on the receiving surface 8 of the receiving device 3 to be described later. That is, the variable focus lens is configured such that the focal point of each incident laser beam coincides with the receiving surface 8 of the receiving device 3. The variable focus lens is configured to be able to move the focus position by changing the lens position. The configuration of the variable focus lens may be a configuration in which the surface shape of the lens formed at the liquid-liquid interface is variable using an actuator.

  The receiving device 3 is a moving body and receives the laser light emitted from the transmitting device 2. The receiving device 3 includes a photoelectric conversion device 9, a light intensity measuring device 10, a position specifying device 11, and a position adjusting device 12.

  The photoelectric conversion device 9 converts laser light incident on the receiving surface 8 into electrical energy. As shown in FIG. 2, in this embodiment, the photoelectric conversion device 9 uses a two-dimensional photodiode array in which a plurality of photodiodes are arranged on a plane. In each of the plurality of photodiodes, an incident laser beam (photon) excites electrons, and a generated carrier moves to allow a current to flow. In addition, the photoelectric conversion apparatus 9 is not restricted above, For example, a solar cell, a phototransistor, etc. may be sufficient.

  The light intensity measuring device 10 measures the light intensity of the laser light incident on the receiving surface 8 for each photodiode. Specifically, the light intensity measurement device 10 acquires the distribution of the light intensity measured for each photodiode as array data, and specifies the peak position of the light intensity of the laser light based on the array data.

  The position specifying device 11 specifies the current position of the receiving surface 8 of the photoelectric conversion device 9. An imaging camera is used as the position specifying device 11, and the current position of the receiving surface 8 is specified by recognizing the photoelectric conversion device 9 from the outside. The position specifying device 11 specifies the current center position of the receiving surface 8 from the current position of the receiving surface 8. The position specifying device 11 is not limited to the above. As the position specifying device 11, a GPS (Global Positioning System) built in the photoelectric conversion device 9 itself, a conventionally known laser radar, an inertial sensor, or the like may be used instead of or in combination with the imaging camera. In this case, the position specifying device 11 can specify the position of the receiving surface 8 based on the movement of the photoelectric conversion device 9 by the position adjusting device 12.

  The position adjusting device 12 adjusts the relative positional relationship between the optical axis of the laser light and the receiving surface 8 of the photoelectric conversion device 9 so that the light intensity of the laser light incident on the receiving surface 8 increases. Specifically, the position adjustment device 12 is configured to be able to communicate with the light intensity measurement device 10 and acquires data related to the peak position of the light intensity of the laser light specified by the light intensity measurement device 10. Further, the position adjusting device 12 is configured to be able to communicate with the position specifying device 11 and acquires data relating to the current center position of the receiving surface 8 of the photoelectric conversion device 9 specified by the position specifying device 11. The position adjusting device 12 is configured such that the center position of the receiving surface 8 approaches the peak position of the light intensity based on data regarding the peak position of the light intensity of the laser light and data regarding the current center position of the receiving surface 8 of the photoelectric conversion device 9. In this way, the relative positional relationship between the optical axis of the laser beam and the receiving surface 8 of the photoelectric conversion device 9 is adjusted. In the present embodiment, the position adjustment device 12 has wings for flying the photoelectric conversion device 9. The position adjustment device 12 may include a propeller, tires and legs that run on the ground, and the like.

  The wireless power supply system 1 </ b> A can wirelessly supply energy from the transmission device 2 to the reception device 3 by converting the laser light emitted from the transmission device 2 into electric power by the reception device 3. The transmission device 2 transmits large energy by condensing the laser light emitted from the plurality of laser light sources 7 at one point. Therefore, the energy of the laser beam irradiated by each laser light source 7 can be reduced. For this reason, the safety | security with respect to eyes can be ensured. The wavelength of the laser light is in the range of 1200 nm to 1400 nm which is the eye-safe band. It is known that the risk to the eyes of laser light in this wavelength range is mainly retinal damage caused by focusing on the retina. However, since the laser beams emitted from the plurality of laser light sources 7 form images at different positions on the retina, the danger to the eyes can be reduced. In addition, since the above wavelength range has the largest energy (16 mW) among the laser beams classified as the safest class 1 in the safety standards, it is possible to transmit large energy to the receiving device 3. it can.

  In the receiving device 3, the light intensity measuring device 10 measures the light intensity of the laser light incident on the receiving surface 8. The position adjusting device 12 adjusts the relative positional relationship between the optical axis of the laser beam and the receiving surface 8 so that the light intensity increases based on the measurement result. Therefore, the laser beam can be received by positioning the center position of the receiving surface 8 at a position where the light intensity of the laser beam is higher. For this reason, energy can be received efficiently. Further, since the band gap of the photodiode matches the wavelength of the irradiated laser light, the energy conversion efficiency can be increased.

  In the above example, an example in which energy is wirelessly supplied from the transmission device 2 to the reception device 3 has been illustrated. The laser irradiation device 4 of the transmission device 2 may be further configured to modulate a plurality of laser beams corresponding to desired transmission data. For example, by providing the laser irradiation device 4 with an optical modulator, it is possible to modulate the laser light corresponding to the transmission data and transmit the modulated laser light. Further, the photoelectric conversion device 9 of the reception device 3 may be configured to demodulate transmission data from the received laser light. For example, the photoelectric conversion device 9 can receive the transmission data of the laser light by demodulating the laser light from the transmission device 2 into an electrical signal. As transmission data, the signal which instruct | indicates the movement of the receiver 3 which is a mobile body may be included. In the above example, an example in which data related to the current center position of the receiving surface 8 of the photoelectric conversion device 9 is transmitted from the position specifying device 11 to the position adjusting device 12 is illustrated. Instead of this example, the position specifying device 11 transmits data related to the current center position of the receiving surface 8 of the photoelectric conversion device 9 to the transmitting device 2, and the transmitting device 2 adjusts the position of the data using laser light. You may transmit to the apparatus 12. Further, the position specifying device 11 transmits data related to the current center position of the receiving surface 8 of the photoelectric conversion device 9 to the transmitting device 2, and the irradiation direction control device 4 determines the optical axes of the plurality of laser beams based on the data. The position and direction of intersection at one point may be changed, or the transmission apparatus 2 itself may move so that the optical axes of a plurality of laser beams intersect at the reception surface 8 based on the data.

  Next, a wireless power feeding system 1B according to the second embodiment will be described. Hereinafter, only differences from the configuration of the first embodiment will be described, and detailed description of the same configuration as that of the first embodiment will be omitted. The same applies to other embodiments.

  The wireless power feeding system 1B of the present embodiment is different from the first embodiment in the configuration of the laser irradiation apparatus of the energy transmission apparatus. As shown in FIG. 3, the laser irradiation apparatus 4a has one laser light source 7a, a plurality of optical fibers 7b, and a plurality of collimating lenses 7c. The laser beam emitted from the laser light source 7a is branched into a plurality of laser beams by a plurality of optical fibers 7b. A collimator lens 7c is provided at the tip of each of the plurality of optical fibers, and a plurality of parallel laser beams are emitted from the collimator lens 7c toward the variable focus lens of the irradiation direction control device 6. The intensity of each of the branched laser beams is 16 mW or less. The branched laser light is condensed on the receiving surface 8 of the photoelectric conversion device 9 of the receiving device 3 via the variable focus lens of the irradiation direction control device 6.

  Also in the wireless power feeding system 1B of the second embodiment, since the laser light emitted from the laser light source 7a is branched, the same operational effects as the wireless power feeding system 1A of the first embodiment can be obtained.

  Next, a wireless power feeding system according to the third embodiment will be described. The wireless power feeding system of the present embodiment is different from the first embodiment in the configuration of the irradiation direction control device of the energy transmission device. As shown in FIGS. 4 to 6, the irradiation direction control device 6 a includes a solenoid actuator 14, a plurality of reflectors 15, and a spring 16.

  The solenoid actuator 14 installs the movable iron core 14b in the solenoid coil 14a, and obtains an electromagnetic force by flowing a current through the solenoid coil 14a. By this electromagnetic force, the iron core 14b moves up and down. One end of a spring 16 is connected to the iron core 14b, and a reflector 15 is connected to the other end of the spring 16. The reflector 15 reflects the laser light. In the present embodiment, six reflectors 15 are arranged in a circle around the solenoid coil 14a. As the reflector 15, for example, a mirror-polished metal such as Al, Au, or Pt, a Si wafer, or a metal film formed on the Si wafer can be used. The size (area) of each reflector 15 is not particularly limited as long as it is larger than a size that allows a plurality of irradiated laser beams to enter.

  The operation of the irradiation direction control device will be described. As shown in FIGS. 5 and 6, the irradiation direction control device 6 a can tilt the plurality of reflectors 15 by driving the solenoid actuator 14. Thereby, the direction of the reflected light of the laser light can be inclined toward the center direction of the solenoid coil 14a with respect to the incident direction of the laser light. Moreover, since each reflector 15 inclines uniformly, reflected light can be made to cross | intersect at one point. Moreover, since the inclination angle of the reflector 15 can be adjusted by adjusting the current flowing through the solenoid coil 14a, the position of the focal point of each reflected light can be changed.

  In addition, as shown in FIG. 7, the laser light source 7 can be attached to each of the other ends of the spring 16 to irradiate laser light, or as shown in FIG. 8, it is irradiated from a single laser light source 7a. It is also possible to irradiate a plurality of laser beams by branching the laser beams by a plurality of optical fibers 7b and through collimating lenses 7c. In this case, the irradiation direction is changed by controlling the direction of the laser light source 7 and the collimating lens 7c itself by the solenoid actuator 14. The irradiation direction control device 6a is not limited to the solenoid actuator, and the irradiation direction of the laser light may be controlled by a piezoelectric actuator or a motor. Moreover, you may use the structure which makes an electromagnet in a reflector and makes the shape of a reflector variable by applying electromagnetic force. By deflecting the reflector by electromagnetic force, the reflection direction of the laser light can be controlled. As described above, the wireless power feeding system according to the third embodiment can achieve the same effects as the wireless power feeding system 1A according to the first embodiment. The configuration of the present embodiment may be used for the wireless power feeding system 1B of the second embodiment.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

1A: Wireless power feeding system 2: Energy transmission device 3: Energy reception device 4: Laser irradiation device 6: Irradiation direction control device 7: Laser light source 8: Reception surface 9: Photoelectric conversion device 10: Laser light intensity measurement device 11: Adjustment device 12: Positioning device

Claims (16)

An energy transmission device,
A laser irradiation apparatus for irradiating a plurality of laser beams;
An irradiation direction control device for controlling the irradiation direction of the plurality of laser beams;
With
The irradiation direction control device is an energy transmission device that crosses optical axes of the plurality of laser beams at one point.   The energy transmission device according to claim 1, wherein the irradiation direction control device is configured to be movable at a position where optical axes of the plurality of laser beams intersect.   The irradiation direction control device is configured to be movable at a position where optical axes of the plurality of laser beams intersect based on a position of a receiving device that receives energy from the plurality of laser beams. 2. The energy transmission device according to 2.   4. The energy transmission device according to claim 1, wherein each of the plurality of laser beams has a wavelength in a range of 1200 nm to 1400 nm. The laser irradiation apparatus has a plurality of laser light sources,
The energy transmission device according to any one of claims 1 to 4, wherein a laser beam emitted from each of the plurality of laser light sources corresponds to each of the plurality of laser beams.   The energy transmission according to any one of claims 1 to 4, wherein the laser irradiation device is configured to irradiate the plurality of laser beams by branching a laser beam irradiated from one laser light source. apparatus.   The wireless electric power feeding system which has an energy transmitter as described in any one of Claims 1-6. An energy receiver,
A photoelectric conversion device that converts laser light incident on the receiving surface into electrical energy;
A light intensity measuring device for measuring the light intensity of the laser light incident on the receiving surface;
A position adjusting device that adjusts the relative positional relationship between the optical axis of the laser beam and the receiving surface of the photoelectric conversion device so that the light intensity of the laser beam incident on the receiving surface increases;
An energy receiving device. The light intensity measurement device is configured to measure a light intensity distribution in the reception surface of the laser light incident on the reception surface of the photoelectric conversion device,
The energy reception according to claim 8, wherein the position adjustment device adjusts a relative positional relationship between an optical axis of the laser light and the reception surface of the photoelectric conversion device based on a light intensity distribution of the laser light. apparatus.   The position adjusting device identifies a peak position of the light intensity of the laser light based on a distribution of the light intensity of the laser light, and the light of the laser light so that a center position of the receiving surface approaches the peak position. The energy receiving device according to claim 9, wherein a relative positional relationship between a shaft and the receiving surface of the photoelectric conversion device is adjusted.   The energy receiving device according to any one of claims 8 to 10, wherein the photoelectric conversion device has a photodiode array including a plurality of photodiodes. A position specifying device for specifying the current position of the receiving surface of the photoelectric conversion device;
The position adjusting device adjusts a relative positional relationship between an optical axis of the laser beam and the receiving surface of the photoelectric conversion device based on a current position of the receiving surface of the photoelectric conversion device;
The energy receiver as described in any one of Claims 8-11.   The wireless electric power feeding system which has an energy receiver as described in any one of Claims 8-12. The energy transmission device according to any one of claims 1 to 6,
The energy receiving device according to any one of claims 8 to 12,
An energy transmitting and receiving device. The laser irradiation device of the energy transmission device is configured to modulate the plurality of laser beams corresponding to transmission data,
The energy transmission / reception device according to claim 14, wherein the photoelectric conversion device of the energy reception device is configured to demodulate the transmission data from the received laser light. A wireless power feeding system comprising the energy transmitting / receiving device according to claim 14.

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