Optical wireless power supply system
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- WI CHARGE
- Filing Date
- 2025-02-18
- Publication Date
- 2026-05-26
Smart Images
Figure 0007865705000024 
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Abstract
Description
[Technical Field]
[0001] This invention relates to the field of wireless power beam radiation, and in particular, in applicable cases, to a home environment. The use of laser-based transmission systems to beam optical power onto mobile electronic devices. Regarding. [Background technology]
[0002] For many years, the ability to transmit power to remote locations without requiring a physical wired connection has been a challenge. There is a pressing need for this. This need is driven by batteries that require periodic recharging. As portable electronic devices have become more common, this has become increasingly important over the past few decades. Such mobile applications include mobile phones, laptops, cars, toys, and other devices. This includes wearable devices and hearing aids. Currently, the latest battery capacity and smart Typical battery usage for a Tophone is such that it needs to be charged once a day. Therefore, the need for remote wireless battery recharging becomes important.
[0003] Battery technology has a long history and is still under development. In 1748, Benjamin F The Lanklin was the first battery made from a Leyden jar, and thus the first electric power generator. The source was described. This resembled a row of cannons (a cannon battery) (hence the battery). (It became known as...). In the latter half of 1800, Volta invented the copper-zinc battery. This was... It was truly portable. The first rechargeable battery, namely the lead-acid battery, was 18 Invented by Gaston Planté in 1859, rechargeable batteries have been a vital energy source ever since. The increase in density has led to various developments, from the initial lead oxidation chemistry to current lithium-based chemistry and zinc air chemistry. The energy density of a rechargeable battery is shown in terms of both weight and volume parameters. As can be seen in Figure 1, it is less than 8 times. At the same time, portable electronic / electrical devices are used to... The amount of power consumed reaches a point where several full battery charges need to be topped up daily. Yes, they are.
[0004] Nearly a century after the invention of the battery, during the period from 1870 to 1910, Tess Ra attempted to transmit power over long distances using electromagnetic waves. Since then, transmitting devices and It can securely reach remote locations that may be significantly farther than the receiving device. Many attempts have been made to transmit power. This was in the 1980s with SHARP (static Stationary High Altitude Relay Platform From NASA, which led the Relay Platform project, in 2007 This ranges from Marin Solyacic, who conducted experiments with a system similar to Tesla's, to... ru.
[0005] Nevertheless, so far, it has not allowed wireless power transfer to mobile devices. There are only three commercially available technologies, namely, the following: Magnetic induction... this is typically limited to a range of only a few millimeters. Photovoltaic cells... This is the level of usability in a room with sunlight or normal (safe) lighting. When illuminated by any of the artificial lights, the size relative to the mobile phone is 0. It cannot generate more than 1 watt of power. Energy harvesting technology... This converts RF waves into usable energy, Under current practical circumstances, it cannot operate at more than 0.01W. RF signal This is because transmission is restricted due to health and Federal Communications Commission (FCC) regulations. On the other hand, typical batteries in portable electronic devices have a capacity of 1 to 100 watt-hours, and are suitable for daily use. It typically requires charging. Therefore, it requires fairly high power transfer over a fairly long range. Shipping is required.
[0006] Therefore, even portable electronic devices that typically have rechargeable batteries are viewed from a broader perspective. The need to safely transport electricity over fields and areas larger than several meters remains unaddressed. It is essential.
[0007] Using collimated or intrinsically collimated electromagnetic waves, particularly laser beams Several attempts have been made to transport electricity in residential environments. However, The commercial applicability of the product to the mass market is currently limited. Before launching a commercial system, several issues need to be resolved. That is, We should develop a secure system. We should develop a cost-effective system. Contamination such as dust and fingerprints or spilled liquids, vibration, beam obstruction, and installation by unqualified personnel. The system can withstand the hazards of a normal household environment, including being placed and occasionally falling to the floor. We should develop a system.
[0008] The currently permitted transmission laser power levels are sufficient to provide a useful amount of power without complex safety systems. It is insufficient to empower them. For example, in the United States, the federal rules revised in April 2014 Collection, Title 21, Volume 8 (21 CFR Section 8), Chapter I, Sub-Chapter J Part 1040 deals with performance standards for light-emitting products, including laser products. Furthermore, there are Class I, Class III-b and Class IV lasers (Class II, II a and IIIa are lasers in the 400nm to 710nm range, for example, visible lasers. For lasers outside the range, Class 1 is considered safe for general public use, but Class IIIb and IV are considered dangerous.
[0009] Refer to Figure 2 here. This shows the above 21 CFR sector for exposures of 0.1 to 60 seconds. MPE (Maximum Permissible Exposure) for a Class I laser with a pupil diameter of 7 mm using a 8-degree laser. In the graph showing the (Imma Permissible Exposure Value) Yes. The following can be seen from the graph above: (i) The maximum permissible exposure level is generally (however (Not always), increases with wavelength, and (ii) specified in Section 8 of 21 CFR To meet the specified requirements, even if a person enters the beam and the laser is turned off 0.1 seconds later, Light not exceeding 1.25 W can be transmitted at wavelengths longer than 2.5 μm. This also reduces the limiting number of digits. In other words, without some kind of safety system, it would be only a few millimeters. Watts of laser power can be transmitted. This can be converted back into electricity, but only a small amount. This provides a significantly smaller power supply than is required to charge portable electronic devices. For example, cellular phones require 1 to 12 watts to charge, depending on the model.
[0010] To transmit power higher than that of a Class 1 laser MPE, a safety system is required. In a residential environment where people who have not received training may approach, a device that transmits a significant level of electricity is, To the best of the applicant's knowledge, it has not yet been commercialized.
[0011] Building a transmission system with a robust safety system is difficult. The detection level is very low compared to the power that needs to be transmitted, and the system operates. The environment is uncontrolled, and many unpredictable scenarios can arise during operation.
[0012] Fingerprints and dust scatter laser light, and transparent surfaces reflect or scatter the light. It is common knowledge in the industry that when high power is being transported, a reliable safety system must be in place. A Class IV (or IIIb) laser is required. Even scattered radiation from the main beam is dangerous. (21CFR revised April 2014) According to Section 8, Chapter I, Subchapter J, Part 1040, 0.5W B Laser radiation in the 400nm to 1400nm range, exceeding the power output, typically requires exposure times longer than 0.5 seconds. In contrast, it is considered a Class IV laser, and even scattered radiation from such a laser can be dangerous. Such a laser must have a lock key and a warning sign similar to that shown in Figure 3. There is a reason for this. Here, the warning is also related to "scattered radiation," and the user of the laser is These people should always wear safety glasses, and are typically trained professionals. All aspects of it are laser power transmission systems available for home use to charge mobile electronic devices. This is far from the acceptable conditions for using a stem.
[0013] Prior art typically involves anti-reflective coatings on surfaces to prevent such reflections. The (active) film is applied to block any reflections that may occur despite this. It is used in combination with a precise beam blocking structure. However, in the prior art The AR film solution used is that dust or spilled liquids accumulate on its surface, or For example, it is prone to failure due to wear and tear caused by improper cleaning. Well, beam blocking solutions typically severely restrict the system's field of view, so modern mobile It is bulky compared to the dimensions of other electronic devices.
[0014] Therefore, the prior art prevents the power beam from scattering and reflecting in undesirable directions. There is a lack of reliable mechanisms for stopping this "small occupied area". Reflection is caused by a transparent surface carelessly placed between the transmitter and receiver. Therefore, the optical characteristics of the transparent surface may be affected by a vast number of different transparent materials, or Liquid spills and fingerprints can accumulate on the external surface of the system, typically on the front of the receiver. It could be affected.
[0015] The third problem with the solutions proposed in the prior art is that such safety systems are generally A mechanism is needed to ensure good alignment between the power beam system and the safety system. Therefore, both systems will no longer exceed their safety limits. The force beam dissipates sufficiently or is sufficiently attenuated (or these factors and any other factors) (Combination) Up to this point, the sights can be aimed on the same axis. This means that even at a distance, the range is almost unrestricted. Collimated cruisers typically fail to do so, and even exceed safety limits over very long distances. This is extremely difficult to achieve with S-IV or IIIb laser beams.
[0016] One of the operating principles of prior art used to construct such safety systems is the beam diameter. The objective is to optically detect a transparent surface that can be positioned along the path. However, the beam diameter The transparent surfaces that can enter the road are made from a vast number of different transparent materials and have an anti-reflective (AR) coating. Unless the beam is absorbed or the material does not absorb the beam, it is almost ineffective for the optical system. They are positioned at an angle close to the Brewster angle so that they become invisible. However, each The light absorption levels of different materials vary and can even be negligible, and optical systems that depend on light absorption Since constructing it is highly material-specific, and the number of available materials is extremely large... Therefore, such systems tend to be complex, large-scale, and expensive, and are not properly designed. As far as is, especially considering that it is intended to be a critical safety system, it must be reliable. That's not the case. Relying on reflection to give the beam a detectable attenuation also has its problems. The surface is coated with an anti-reflective film, or at a near-Brewster angle with respect to the beam. When positioned in that location, reflection can be minimized at that particular spot on the surface. be.
[0017] Other limitations of prior art systems include the need for good beam quality (low m) to achieve high efficiency. 2 The value is large Using a laser combined with a large optical system (for example, Patent Documents 1 and 2 are...) While a wide aperture is typically used for the laser beam, Patent Document 3 describes a small A wavelength of 0.8 μm is used to allow for optical systems and reduce the cost and size of the optical system. do.
[0018] Therefore, a set that overcomes at least some of the disadvantages of the prior art systems and methods. There is a need for a laser power transmission system with built-in safety features.
[0019] Each disclosure of the publications referenced in this section and other sections of this specification is subject to change. The entire thing is incorporated here as a reference. [Prior art documents] [Patent Documents]
[0020] [Patent Document 1] U.S. Patent No. 6,407,535 (B1) [Patent Document 2] US Patent No. 6534705 (B2) [Patent Document 3] U.S. Patent No. 5,260,639 [Overview of the Initiative]
[0021] One of the main challenges of wireless power transmission is to create a system that is safe, low-cost, small, and powerful. To construct a transmitter and receiver that can transmit (for example, a significant level of power) It is located there. To enable powerful and small transmitters and receivers, the beam's radiance is Maintain as high a level as possible throughout the entire optical path, but especially at the output section of the transmitter. This is essential. All components in the optical path must incur a certain amount of radiance loss. To cause. The term radiance efficiency is used several times in this specification. The usual meaning of this is the radiance that goes out of the optical component. This is the ratio of the incoming beam's radiance to the incident radiance. It can be configured in various ways. Regarding the components, for example, the mirror can be tilted at different angles. Conversely, different radiation efficiencies may exist.
[0022] Generally, the system as a whole needs to have the highest possible radiation efficiency, ideally 60%. Efforts should be made to obtain typical radiation efficiencies exceeding 90% or even 95%.
[0023] The radiation efficiency of the transmitter is generally far more important than the radiation efficiency of the receiver. There are two main factors that reduce the luminance: namely, the laser system and the transmission. This refers to the radiative efficiency of the container. In addition to these factors, other minor factors also have an influence.
[0024] Lasers with high radiance values are generally large and complex, while lasers with low radiance values The lasers used are typically small and simple. Current systems have improved safety features. Because it typically uses rare wavelengths that it tolerates, the laser radiance is limited. Unconventional, small-wavelength, low-cost, high-radiance lasers are not yet widely available. It tends to increase the cost of the system rather than improve performance.
[0025] Prior art systems such as those described in Patent Documents 3 and 4 allow for compact transmitters and receivers. Use the shortest possible wavelength (0.8 μm or 0.532 μm). However, currently Since this system utilizes long wavelengths, a different method is needed to reduce the size of the system. You need to use it.
[0026] The long wavelengths used by the current system are the same as those used in the present U.S. Patent Application No. As explained in issue 14 / 811,260, virtually all plastic materials By using wavelengths that are specifically absorbed, transparent plastics in the beam path can be removed. Enables detection of the 'ku'.
[0027] Even if the material is opaque or partially opaque, if it is placed inside the beam, the beam It can be easily detected by measuring the decay of the m. However, some The material is transparent or nearly transparent, and even such transparent materials are significantly difficult to detect. Yes, there are two main groups of transparent solid materials: organic materials and inorganic materials. Yes, there are. The number of inorganic transparent solid materials available to the general public is quite limited. This includes glass, several commonly used semiconductor materials, quartz, as well as diamond and ruby. - and several natural minerals such as calcite. Therefore, from inorganic transparent materials A detection system for reflections can be built to cover all similar scenarios. .
[0028] On the other hand, the potential for the general public to use different organic transparent materials is enormous. Transparent materials are always included in the list. This is an important issue. This is because it becomes virtually impossible to characterize it academically.
[0029] Polymers are an important group of transparent organic materials, and the present invention is intended to operate on them. It is used as a sample group to help illustrate the manner in which the polymer is used. It consists of long-chain monomers. The backbone of such polymers is typically either carbon or silicon. It consists of the following. Figures 4-9 show the chemical structures of some commonly used transparent polymers. Figure 4 shows a polymethyl methacrylate (PMMA) chain. Figure 5 shows the structure of polycarbonate. Figures show the structure. Figure 6 shows the polystyrene structure. Figure 7 shows nylon 6,6. Figure 8 shows poly The polypropylene chain is shown. Figure 9 shows the polyethylene chain structure.
[0030] As observed, the chemical structures of the sample polymers shown are very different, and these The absorption spectrum of the polymer is determined by many factors, including the density of the material, the amount of reagent residue, and the length of the chain. It depends on the factors. Nevertheless, all of the transparent polymers mentioned above have some common characteristics. It has chemical bonds, particularly CC bonds and CH bonds. This is commercially available, For polymers that are almost entirely organic and would be detected by the disclosure system, or Silicones, polysilanes, and polygermanenes that may be detected by the system disclosed in this document. And for semi-organic silicon polymers such as polystanane or polyphosphazene, This applies.
[0031] Separately, transparent materials that are not carbon-based and are available to the general public (most are The number of glass types (composed of various types of glass) is quite limited. Most of them have a transmission spectrum. It has readily available data.
[0032] Either the vibrating CH or possibly the CC bond within the polymer is excited by the laser. If the system is designed to be activated, then one of such polymers will be placed into the beam. Monitoring the power drop caused by the polymer during positioning. This makes detection easier. This is because absorption of CH or CC bonds is always present, and always, It is assumed that the wavelength will match the laser wavelength. The rotational peak is also for this purpose. It can be used, but rotational peaks are unreliable in polymers, therefore for this purpose For this purpose, vibrational CH (or CC) absorption is well suitable.
[0033] Here, refer to Figure 10, which shows a chart of typical absorption regions for different polymer bonds. In almost all of the polymers shown, the range is 2900-3200 cm². -1 Nearby CH stretch vibration A motion is observed. Therefore, this is a change in transmitted power obtained from the absorption band. It can be used as a trigger for an absorption mechanism in a safety system. However, Regarding these absorption bands, there are two problems that prevent them from being useful for this purpose. ru.
[0034] (i) CH oscillatory absorption lines are typically very steep, and their exact frequencies are polymer Because it changes with each step, the laser will not excite other polymers even if it excites one polymer. This is possible. That is, the laser is precisely tuned to the intrinsic CH vibration line of the polymer. It won't be absorbed unless it's absorbed. (ii) Such CH vibration peaks are generally due to the material section being several mm thick, and therefore the beam Attenuation is 20-50% (i.e., even trace amounts of material in small containers can be detected). This is a moderate absorption peak, meaning it is effective (20-7 per cm of material). Absorption peaks with 0% attenuation and intensity (attenuation exceeding 70% per cm) are generally quite Because they are easily detected, these absorption peaks can be used to build a robust system. It cannot be used.
[0035] In commercial systems designed for consumer environments, fingerprints are a common problem. Under normal operation, the system should not fail simply because fingerprints accumulate. Instead, if there is a risk that exceeds the safety limits, the system will shut down the transmission. It should be done. In order to do this, the system should detect beam blocking. Transmission should not be stopped due to any fingerprints deposited on the receiver. If an absorption peak of a certain degree is used, in the event that a fingerprint or other mark appears on the external optical surface of the receiver or transmitter, If any other contamination has accumulated, the beam will be significantly absorbed, resulting in a failure of power transmission. This happens because fingerprints absorb the beam, causing a system failure due to poor control. This is also because it contains organic compounds that leave fingerprints. Organic substances, like fingerprints, are typically found on the outside. The system should be able to operate in environments where deposits may accumulate on the surface of optical components. While the laser beam successfully crosses the fingerprint, there is a risk of dangerous penetration that could be inserted into the beam. It is necessary to build a system in which bright items are detected by a safety system. If the system utilizes a weak absorption band instead of a moderate or strong absorption band, then the system The device should work even with a fingerprint, and should shut down based on an electronic decision. Therefore, this does not constitute a control failure.
[0036] 800cm -1 From 1300cm -1 If we look at the CC absorption band that extends to this point, This is because narrowband lasers can almost certainly avoid narrowband absorption peaks in this region, even with a broadband laser. The peak in question is 800 cm. -1 ~1300cm -1 While it is located within that range The typical width is very small and can easily be missed by narrowband lasers. In addition, as can be seen in Figure 11 below, this band is different for some polymers. It will disappear. In this case, 800-1300cm -1 There is no visible absorption peak, C -C bonds are absent, and aromatic carbon-carbon bonds or C=C bonds and COC bonds are present. There are several polymers that can be substituted.
[0037] Further problems arise from the absorption intensity of CC lines. For symmetrical compounds such as polyethylene... While detection of the nephew can be almost impossible, for other compounds, on the surface of the receiver... Even a weak fingerprint can become strong enough to disable the system, so a significant portion of the power The fingerprint is absorbed and renders the device unusable. The fingerprint can accumulate on the optical surface. In order to enable the system's operation, most organic polymers do not differ much from each other. We need weak but not too weak absorption lines found in the polymer. A laser tuned to a specific peak is used in conjunction with a system that operates near that peak. It should be. As can be seen from Figure 10, commonly used polymers have the absorption band shown in the figure. Such a peak does not exist.
[0038] A system for transmitting optical wireless power to a power receiving device, (a) an optical resonator fitted to emit a light beam having end reflectors, (b) A gain medium positioned inside the optical resonator and having a first bandgap energy It is a body, thermally attached to a cooling system to amplify the light passing through it. The configured gain medium and (c) A collimator lens that reduces the emission of the light and has high radiation efficiency (over 50%), (d) A driver that supplies power to the gain medium and controls the small signal gain of the gain medium, (e) configured to direct the light beam in at least one of multiple directions, typically with high emission A beam steering device having a firing efficiency (typically exceeding 50%), (f) A light beam is configured to convert into power having a voltage, and a second bandgap is configured Optical / power converters having a thickness that acts as both an energy source and an absorption layer (typically a semiconductor). and, (g) Convert one voltage of the power generated by the optical / power converter to a different voltage. A voltage converter that conforms to the requirements and includes an inductor, an energy storage device and a switch, (h) related to the optical / power converter and between the gain medium and the optical / power converter At least one optically arranged surface, (i) Configured to provide a signal indicating that the light beam has collided with the optical / power converter. The detector, (j) A safety system that evaluates the potential for safety violations, (k) Control the status of at least one of the beam steering device and the driver. A controller that conforms to the above and receives at least a control input signal from the detector and Includes, (l) The at least one surface is such that (i) in more than one direction, or (ii) reflected light is The surface has a virtual focus positioned to be far from the optical resonator. , or (iii) the reflected light is at least 1 cm in the direction of the optical resonator relative to the surface It has the characteristic of reflecting a small portion of the incident light so that it has a real focal point positioned at a certain location. (m) The controller (i) controls the driver to change the small signal gain of the gain medium (ii) changing the radiance of the light beam, and (iii) by the driver (iv) Changing the power supplied and changing the scan speed of the beam steering device. (v) changing the scan position of the beam steering device, and (vi) the light by at least one of recording a scan position that defines the position of the power converter configured to respond to a control input signal received from the detector (n) the gain medium is a semiconductor device or solid host doped with Nd ions and has a wavenumber in the range of 8,300 cm -1 to 12,500 cm -1 and includes a filter that attenuates radiation at at least one frequency having a wavenumber in this range (o) the thickness of the active semiconductor layer of the optical / power converter is large enough to absorb most of the light beam, but not so large as to significantly reduce the quantum efficiency of the semiconductor layer is selected such that (p) the second bandgap energy is smaller than the first bandgap energy (q) the first bandgap energy is 0.8 eV to 1.1 eV (r) the switch has a closed series resistance smaller than R given by the formula
Number
[0039] In any of these systems, the different voltages are generated by an optical / electrical converter. The voltage can be higher than the voltage that is being measured. Furthermore, the status of the beam steering system is the beam steering This can be either the aiming direction and / or scanning speed of the rudder.
[0040] Furthermore, in any of the above systems, the light beam is at least 800 kW / m 2 It may have a radiance of / steradians.
[0041] Other implementation examples include one end reflector of the resonator being (i) a dielectric mirror, (ii) a black (iii) a Gummiller, a Fresnel reflector, or (iv) a dielectric having a different refractive index This may include any of the above systems, which are mirrors made of alternating layers of semiconductor material. In addition, the gain medium is a transparent solid host material or semiconductor doped with Nd ions. It can be any of the body. In such cases, the system will also be 8300cm -1 Larger than It may include a filter that extracts radiation having a certain wave number. When the gain medium is a semiconductor, quantum A dot-gain medium may be advantageous.
[0042] In a more typical implementation of the above system, the cooling system includes a heatsink and a pelvic. It can be at least one of a condenser diode and a liquid cooling plate. It may be equipped with a fan. It is possible. In addition, the gain medium is a solder layer with a thermal resistance of less than 200 Kelvin / Watt. It can be attached to the cooling system using [this method]. In any case, the cooling system is [advantageous] The thermal resistance between the medium and the surrounding air can be made to be less than 200 degrees Kelvin / Watt. .
[0043] In any alternative implementation of the above system, the optical / power converter can be used as a photovoltaic cell. In such cases, the photovoltaic cell can become a III-V device. In any case, photovoltaic The series resistance of the power transducer should be less than 1 ohm.
[0044] Optical / power converters typically have a conductor on them. The conductor has at least 0.02 / μ 10 It has a thickness of μ. 10 This is a decimal decay factor measured in units of 1 / m. It is a number.
[0045] Such a conductor has at least (0.01*Pρ) / (V 2 *χ) Having a thickness of 1 meter It should be. Here, P is the transmission, measured in watts, absorbed by the photovoltaic cell. V is the power, ρ is the intrinsic electrical resistivity of the conductor, and V is the maximum power generated by the photovoltaic cell. This is the voltage emitted at the point of force application, and χ is the ratio of the area of the absorption layer covered by the conductor. ru.
[0046] Further implementation of the above system would involve an inductor that is a series resistor measured in ohms. The resistor measures the square of the first bandgap energy, measured in joules, in watts. The driver power is 2 × 10 -40 It should be less than the result of dividing by the multiplier.
[0047] In other implementations, the energy storage device is either a capacitor or a rechargeable battery. It could be any of these.
[0048] Further implementation of the above system would involve inputs from various sensors and monitors. This includes at least one safety system for estimating the probability of a safety violation. Unlike the radar system in Reference 1, which only provides actual measurement data without indicating the probability of error, this system provides actual measurement data without showing the probability of error. This system differs from prior art systems. This system is in contrast to the safety violations that are actually detected. It differs in that it provides a signal indicating the probability of a safety violation. This offers several significant advantages. This is permissible. Firstly, the system is characterized by low signal / noise or signal interruption. In situations that potentially pose problems, the goal is to distinguish between high-risk and low-risk situations. Because it allows for greater responsiveness, it can respond differently to each situation. Example For example, a dirty opening could lead to poor alignment or similar issues, resulting in a low risk. This situation can be described, for example, as a high-probability beam intrusion, or an unreasonable beam charge, whether high or low. It can be treated differently from high-risk situations such as force. Secondly, the system can handle ten To achieve high detection accuracy, we combine probabilities from different safety systems to unify the results. It can be expressed as a rate. For example, in a changing environment, typically 10 per hour. -9 Failure of failure If the system is designed to have a rate, it will provide such reliable measurements without failure. There is no single safety system that can achieve this. However, a combination of safety systems The combination may have a good failure probability. Such data can be combined with the probability of errors. Furthermore, the statistical correlation of errors from both safety systems is known or estimated. If approximated, data from the two systems will yield data with a significantly higher probability. Such reliable data can be combined in such a way as signals. / Based on noise, component temperature, and measurements on the same or similar devices From the preloaded data, uploaded by the manufacturer or seller or user This can be estimated from the user input information provided by the system.
[0049] Further implementations of the above system involve using a lens to direct the output beam of the laser resonator. Using this, the lens is collimated (or nearly collimated) to at least one axis. This uses lenses with a high numerical aperture (NA). It needs to have a sufficiently high radiance efficiency (typically over 50%).
[0050] Further implementation of the above system would allow the beam deflection mechanism to exceed 50%. It is necessary to have a high radiance efficiency, and furthermore, its center of rotation is the weighted average of the beam. To get as close to the point as possible, or to the point of maximum beam intensity, or to slightly more than 50% of the beam intensity. It needs to be positioned as close as possible to the center of the degree line or the 90% intensity line.
[0051] The overall radiance efficiency of 30% for the transmission / reception / conversion process is a system efficiency. This is a desirable level for energy efficiency, but this depends on the available components. It should be understood that this is limited by constraints and environmental conditions, and that 20% or more is limited. It should be understood that levels below 30% are also operational.
[0052] In addition, any of the above systems may include a retroreflector. Furthermore, the gain medium is a It can be electrically or optically excited by a driver. Furthermore, the second bandgap energy is This can exceed 50% of the first bandgap energy.
[0053] Another implementation involves a method for transmitting power from the transmitter to the receiver. This method is: (a) The first power is approximately 6940 cm -1 It is approximately the first harmonic of CH absorption located at 8130cm -1 Electromagnetic waves having a frequency between the second harmonic of CH absorption located at the position This involves converting the electromagnetic waves to at least 8 kW / m 2 / Stellarian Radiation The conversion has a degree, and the conversion is performed by an optical resonator having end reflectors and a laser dry receiving the first power. This is done by using a gain medium connected to a bar, and the gain medium has a voltage of 0.8 eV~ It has a first bandgap energy of 1.1 eV, is placed inside the optical resonator, and is cooled It is thermally mounted to the system and configured to amplify electromagnetic waves passing through it. That thing, (b) The electromagnetic waves are directed to multiple people using a beam steering device controlled by a control unit. To point in at least one direction, (c) Detecting the collision of the beam with a target having an associated partially transparent surface. The display related to the collision is such that the control unit (i) the small signal of the gain medium (ii) causing a change in gain and (ii) causing a change in the radiance of the electromagnetic beam (iii) causing a change in the first power, and (iv) the beam steering device (v) Changing the scan speed and changing the scan position of the beam steering device. (vi) recording a scan position that defines the location of the target, By doing so, it will be used, (d) Light having a second bandgap energy smaller than the first bandgap energy By using a power converter, the electromagnetic wave is converted into a second power having a single voltage. That thing, (e) Inductors, energy storage devices, and formulas
number
[0054] In this method, the switch is,
number
[0055] In addition, detection of a beam collision with a target is performed by detecting retroreflection illumination from that target. Either for use in an output transmitter, or for detecting target illumination using a receiver sensor. It can be done depending on the circumstances.
[0056] Furthermore, in any of the above methods, the second bandgap energy is equal to the first bandgap energy. It can exceed 50% of the top energy.
[0057] A system for optical wireless power transmission to at least one power receiving device, and this The stem is, (i) an optical resonator having multiple end reflectors and adapted to emit a light beam, (ii) 8,300 cm -1 From 12,500cm -1 With wavenumbers in the range of less Both are filters that attenuate radiation for a single frequency and neodymium ions that use optical communication. A gain medium comprising either a (a) semiconductor device or a (b) solid host And it is positioned inside the optical resonator and has a first bandgap energy, , which is thermally attached to a cooling system and configured to amplify the light passing through it Acquisition medium and (iii) A device configured to supply power to the gain medium and the small signal gain of the gain medium A driver that enables control, (iv) Beam control configured to direct the light beam in at least one of multiple directions The rudder and (v) an at least one power receiving device that is arranged to transmit the light beam to a single voltage A light / power converter configured to convert into power, wherein the second bandgap energy A light / power converter having energy, (vi) The light beam is configured to give a signal indicating that it is colliding with the optical / power converter. The detector that was created, (vii) Control the status of at least one of the beam steering device and the driver. A controller adapted to receive a control input signal from at least the detector Controller and Includes, The light beam has a power output of at least 8 kW / m 2 The transmitter has a radiance of / steradians. The overall radiance efficiency of the transmission between the and at least one power receiving device is at It is 20%.
[0058] In such a system, the entire transmission between the transmitter and at least one power receiving device The radiance efficiency should be at least 30%.
[0059] Furthermore, all of the above systems include a voltage converter connected to the output of the optical / power converter. This may further include: In such a case, the voltage converter tracks the maximum power point of the optical / power converter. It may be configured in such a way. In addition, the voltage converter is a DC / DC boost voltage converter. That's fine.
[0060] Furthermore, other implementations may include one of the systems described above, wherein the resonator has at least one induction Includes electro-mirrors.
[0061] Alternatively, the optical / power converter may be a photovoltaic cell, in which case the photovoltaic cell is II It may contain IV semiconductor materials.
[0062] Further implementation examples may include systems such as those described above, which may contain capacitors or rechargeable batteries. The energy storage device may further include a pond.
[0063] Furthermore, other advantageous implementations often involve a system like the one described above, where the inductor is... It may also include: In such circumstances, the inductor is
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[0064] Further systems of this disclosure may be those described above, and such systems are power receiving It is configured to receive information from the signaling device. This information includes battery status, device It may include at least one of the following: identification, required power, required voltage, and key.
[0065] Furthermore, none of the above systems also have a sensor that determines the temperature of the optical / power converter. It may be included. In this case, the sensor responds to the temperature change of the optical / power converter to the light beam. The power may be configured to correct. The output of the temperature sensor is received by the controller. It should.
[0066] According to other implementations described in this disclosure, any such system is photovoltaic light It may further include an optical window positioned between the power converter and the beam steering device. In such cases, the window may have a refractive index of at least 1.5, or at least 1.6. It may be coated with an anti-rejection film.
[0067] In addition, in such a system, the second bandgap energy is equal to the first bandgap energy. It should be smaller than energy.
[0068] Furthermore, the controller directs the beam steering device to at least one power receiving device. It should be adapted to fit.
[0069] According to yet another implementation of the system described in this disclosure, at least one power receiving device A system for optical wireless power transmission to a location is provided. This system is (i) an optical resonator having multiple end reflectors and adapted to emit a light beam, (ii) 8,300 cm -1 From 12,500cm -1 With wavenumbers in the range of less Both are filters that attenuate radiation for a single frequency and neodymium ions that use optical communication. A gain medium comprising either a (a) semiconductor device or a (b) solid host And it is positioned inside the optical resonator and has a first bandgap energy, , which is thermally attached to a cooling system and configured to amplify the light passing through it Acquisition medium and (iii) A device configured to supply power to the gain medium and the small signal gain of the gain medium A driver that enables control, (iv) Beam control configured to direct the light beam in at least one of multiple directions The rudder and (v) an at least one power receiving device that is arranged to transmit the light beam to a single voltage A light / power converter configured to convert into power, wherein the second bandgap energy A light / power converter having energy, (vi) The light beam is configured to give a signal indicating that it is colliding with the optical / power converter. The detector that was created, (vii) Control the status of at least one of the beam steering device and the driver. A controller adapted to receive a control input signal from at least the detector Controller and Includes, The controller in question is, (a) To cause the driver to change the small signal gain of the gain medium, (b) Changing the radiance of the light beam, (c) Changing the power supplied by the driver, (d) Changing the scan speed of the beam steering device, (e) Changing the attitude of the beam steering device, (f) Record the scan orientation that defines the placement of the optical / power converter. By outputting a command that results in at least one of the following, the safety that occurred in the system It is configured to respond to the display of all risks.
[0070] The term "attitude" refers to both the position and angular orientation to which the beam steering device directs the beam. It is understood to be such. Furthermore, the above driver configured to supply power to the gain medium is Furthermore, changing the excitation power input to the gain medium, or completely turning on the driver It is understood that by turning it off, the small-signal gain of the gain medium can be controlled.
[0071] In such a system, the display of safety risks arising in the system is at least optical beams. A detector configured to give a signal indicating that the object has collided with the optical / power converter. The resonance of the beams from the generated signal and from at least one power receiving device It is obtained from the signal generated by the level received in the device.
[0072] All of the systems described in the latter half use a voltage converter connected to the output of the optical / power converter. It may also include: such a voltage converter to track the maximum power point of the optical / power converter. It should be configured as such. In addition, the voltage converter can be used as a DC / DC boost voltage converter. stomach.
[0073] Further implementations of such systems include at least one dielectric mirror in the resonator. It can be seen. Furthermore, the light / power converter may be a photovoltaic cell, and such a photovoltaic cell is II It may contain IV semiconductor materials.
[0074] Further implementations of such systems include energy sources that can be capacitors or rechargeable batteries. These may further include ghee storage devices. In addition, they may further include inductors. Such inductors are
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[0075] Furthermore, all such systems receive information from at least one power receiving device. It can be configured to include: battery status, device identification, required power, It may include the required voltage and at least one of the keys.
[0076] The system may further include a sensor that determines the temperature of the optical / power converter. The device is configured to modify the power of the light beam in response to temperature changes in the optical / power converter. Good. To do this, the output of the temperature sensor should be received by the controller.
[0077] Further examples of such systems include the relationship between the photovoltaic optical / power converter and the beam steering device. It may include a positioned optical window. Such a window shall have a refractive index of at least 1.5. It may have a refractive index of 1.6 or at least 1.6, and may also be coated with an anti-reflective coating. It's okay to be censored.
[0078] Finally, in all of the above systems, the second bandgap energy is the first bandgap energy. It should be smaller than the gap energy.
[0079] In many situations, the maximum power radiated by a system does not meet the safety requirements of that system. From the engineering requirements of the system, and from the power requirements of the receiver (which can change dynamically) ), or other issues, in order to prevent the predetermined maximum value that can be derived from this from being exceeded, It is necessary to do so. In such cases, if the light beam exceeds a certain power, the system will This reduces the small-signal gain of the gain medium, resulting in a decrease in the radiance emitted by the system. It can be done.
[0080] Therefore, further implementations would result in at least one more such system. To provide a signal indicating the power carried by the light beam before it hits the power receiving device. This may include a power sensor. In such a situation, the driver will receive the power from the power sensor. The system can be configured to reduce the small-signal gain of the gain medium when the display exceeds a threshold. Cut.
[0081] In addition, one important indicator of safety risks is "power loss," that is, the system... This is an estimate of power that is not explained. Such power can be lost for the system. However, this can also be a loss of power in a risky manner. Once detected, the system must perform various actions to ensure safe operation. The operation involves reducing beam power, reducing small signal gain, reducing system radiance, and beam This may include biasing of the signal or notifying the user. Therefore, the detector also includes at least one The power receiving device also provides a signal that displays the power it has received. In this case, the safety indicator is less At least one of them is the power displayed by the power sensor and the at least one power receiving device This may be due to the difference with the power displayed by a detector in one of the devices. Subsequently, safety indicators At least one of these may arise from the difference exceeding a threshold.
[0082] Other safety hazard indications can result from beam intrusion sensors that can be optical, or from system stem integrity sensors such as watchdog timers, interlocks, thermistors that can indicate that the system is not safe. In such cases, the system can perform safety operations such as reduction of beam power, reduction of small signal gain, reduction of the system's radiance, deflection of the beam, or notification to the user.
[0083] Therefore, further implementations of the above system can include a beam intrusion sensor adapted to detect when an unwanted object enters the light beam. The entry of an unwanted object constitutes an indication of a safety risk. Alternatively and additionally, such a system can further include an en closure integrity sensor. Here, a warning that the integrity of the enclosure issued by the sensor indicates a safety risk. Such a system can also include a detection device that detects a deviation operation of at least one important subsystem in the system may be included. The deviation operation constitutes an indication of a safety risk.
Brief Description of the Drawings
[0084] The present invention will be fully understood and recognized by the following detailed description received in conjunction with the drawings.
[0085] [Figure 1] Shows the energy densities of various battery chemistries. [Figure 2] Shows the maximum allowable exposure values of lasers for various exposure times according to Title 21, Volume 8, Title 21 of the Code of Federal Regulations (2) (21 CFR Section 8), Chapter I, [Figure 3] Subchapter J, Part 1040 revised in April 2 The example of a warning label for Class IV laser products [Figure 4] Figures 4 to 9 show examples of the chemical compositions of various commonly used transparent polymers. Figure 4 shows a polymethyl methacrylate (PMMA) chain. [Figure 5] Shows the structure of polycarbonate. [Figure 6] Shows the polystyrene structure. [Figure 7] Shows the structure of nylon 6,6. [Figure 8] Shows the polypropylene chain structure. [Figure 9] Shows the polyethylene chain structure. [Figure 10] Shows the IR absorption bands for common organic chemical bonds. [Figure 11] Shows the IR absorption spectrum of polyethylene. [Figure 12] Shows the overtone absorption bands of some common organic chemical bonds. [Figure 13] Figures 13a and 13b show different electronic configurations for converting the output voltage of a photovoltaic cell to different voltages. [Figure 14] Shows the power per square meter reflected by a mirror focused with a beam of radiance 8 kW / m2 / steradian as a function of the numerical aperture. [Figure 15] Figures 15A to 15C show schematic diagrams of exemplary devices according to the present disclosure for avoiding dangerous reflections from the front of a receiver illuminated by the transmitter of the present disclosure. [Figure 16] Shows a schematic diagram showing a detailed description of the optical wireless power supply system of the present disclosure. [Figure 17] It is a graph showing the change in power transmission of the system of Figure 16 as a function of the tilt angle of the beam steering mirror. [Figure 18] Shows a schematic representation of the cooling system for the gain medium of the system of Figure 16. [Figure 19] Shows a schematic diagram showing a detailed description of the system of Figure 16, but further incorporating a safety system. [Figure 20] It is a schematic diagram of the optical / power converter of the systems shown in Figures 16 and 19. [Figure 21] Figure 19 shows a block diagram of the safety system. [Figure 22] Figure 19 shows the output laser beam of the system, which is deflected by mirrors rotating around one or more gimbal axes. [Figure 23] The mirror in Figure 22 is shown rotated so that the beam is deflected by a larger angle than the beam shown in Figure 22. [Figure 24] A schematic representation of the intensity characteristics of a typical deflected beam is shown. [Figure 25] This shows a side view of the laser diode and the lens that manipulates the beam, viewed from a direction perpendicular to the laser's velocity axis. [Figure 26] A block diagram of a complete laser protector is shown. [Modes for carrying out the invention]
[0086] In light of the above considerations, one typical implementation of the optical wireless power transmission system of this disclosure is 6940 cm². -1 The first harmonic of CH absorption and 8130 cm -1 The second harmonic of CH absorption in and It can be a system tuned to operate between such harmonic ranges. It is not a well-known frequency band, and does not contain much chemical information, so it is practically prohibited. It arises from a halted quantum mechanical transition and is only permissible due to its complex mechanism. Therefore, the harmonic band provides a broad and weak absorption band which is precisely what is desirable for this application. It has been found that it is not significantly used in analytical chemistry. Due to its broad bandwidth. While it becomes possible to detect various different polymer compositions, weak absorption can lead to system The device can continue to function even in the vicinity of organic dirt and fingerprints. Therefore, these lines are not very useful for typical absorption measurement applications, but this It is ideal for SCs. Another advantage of these lines is that there are no general absorption lines positioned directly at the same frequency, and therefore, even if the chemical composition of the material changes, the measurement results are not modified so strongly. Many such overtone bands are illustrated in the chart of FIG. 12.
[0087] Electro-optical components operating in that band are lacking and difficult to procure. This is probably because both diode lasers and diode-pumped solid state (DPSS) lasers are not very efficient at that frequency, and only low-power lasers are currently commercially available. Since lasers with the desired parameters at the preferred frequency are not currently available, a laser suitable for this application has to be designed from scratch. It is necessary to design a resonator and a gain medium. It is necessary to construct a laser with a selected frequency and radiance value sufficient to promote a roughly collimated or nearly collimated beam. To achieve good collimation of the beam, a radiance of at least 8 kW / m² / sr is required, and a high-power system for efficient power transmission requires about 800 kW / m² / sr. For small systems operating over long distances, following the same principle, it will be possible to design a fairly high radiance (up to 10 GW / m² / sr) in the future. Receivers used with a radiance below that level will have to be so large that the system becomes difficult to handle. 2 2 *² / sr) 2
[0088] Different mirror settings were used for the resonator. Specifically, gold, silver, or aluminum. High-quality metal mirrors made from [material name] were used. These significantly improved the laser oscillation efficiency. It has been shown that it can be reduced. With dielectric material mirrors, fairly good results have been achieved. Alternatively, Fresnel mirrors have one advantage in that they are low-cost. Other mirrors are Bragg mirrors (which may be dielectrics). Mirrors are stable or... A stable resonator, or the inside of the laser (in a fiber or diode laser) Positioning to form a resonator that is confined to a certain space by a barrier (such as) It is necessary that the gain medium amplifies the beam and resonates inside the resonator. Between mirrors in positions where this is permissible, at least 8 kW / m 2 / Stellarian It is necessary to arrange the components in the resonator so that they have radiance.
[0089] If the gain medium can generate laser oscillations at wavelengths greater than one, the dielectric mirror is Alternatively, you can select to restrict the wavelength to an eigenvalue. This also allows the laser oscillation frequency to be fixed.
[0090] Specifically, 6940cm -1 The first harmonic of CH absorption and 8130 cm -1 odor The mirror shows high reflection for at least one wavelength between the second harmonic of the CH absorption and the wavelength of the chromium absorption. It is favorable when there is a rate.
[0091] Three different approaches can be used for the gain medium.
[0092] 1.DPSS design
[0093] In DPSS design, the gain medium can be an Nd-doped YAG crystal. However, Furthermore, YVO4 crystals, GGG crystals, and glass are also options for transparent hosts. Neodymium is most suitable for operation between the first and second harmonics of the CH band. Therefore, Nd is approximately 7450 cm. -1 This is because it has succession in the vicinity. Nd io The nucleus is typically excited by absorbing radiation from an 808nm laser diode. It is necessary to do so. However, other wavelengths can also be used. Nd-based gain media are 940 0cm -1 Unless a filter is added inside the resonator to block the transitions in the vicinity, or the resonator Unless these undesirable emissions are extracted, the laser tends to oscillate at fairly high frequencies. When such a filter is added, the range becomes 7440-7480 cm. -1 In the laser oscillation To begin, this filtering effect can be achieved by using a prism or grid instead of a filter. This can be achieved by, or by, appropriate color design of the laser resonator.
[0094] 2. Semiconductor lasers
[0095] As an alternative, a semiconductor-based design can be proposed. The wavelength of the semiconductor laser used is... By modifying the laser oscillation bandwidth gap of the semiconductor, tuning can be achieved. Semiconductors, specifically III-V type semiconductors with a bandwidth gap of the order of 1 eV. and, more specifically, but not exclusively, quantum dot type, 690 0cm -1 ~8200cm -1 It emits light at a desired frequency. Specifically, 0.8e A bandwidth gap of V ~ 1.1 eV yields good results and is generally used, at least partially. It is absorbed by virtually all of the polymers used.
[0096] 3. Various alternative designs may be included, such as Bragg mirrors and / or fiber loop mirrors. Nd-doped fiber lasers can also be used in the systems described in this disclosure. Alternatively, a Raman-shift fiber laser can also be used.
[0097] During operation, the gain medium heats up, so it must be cooled to prevent wavelength shift and efficiency degradation. It must be. If the gain medium is properly cooled, it should be at least 8 kW / m 2 / Stellagian It has a radiance of 6900 cm². -1 ~8200cm -1 A beam with the frequency is emitted. The excitation power or current can be increased until it is reached. Such a beam is almost Because it can be collimated, it is attenuated by most organic substances containing polymers that are acceptable for detection. Nevertheless, it is not strongly absorbed by contaminants such as fingerprints.
[0098] Laser gain media are typically configured to operate at temperatures below 150 degrees Celsius. When the temperature typically exceeds a certain level, around 250 degrees Celsius, a certain number of problems can arise. ru.
[0099] Firstly, especially in 3-level and 4-level lasers, low-level excited states accumulate As a result, and further due to thermal recombination of semiconductor charge carriers, the luminescence efficiency is significantly lower. It is possible to do so.
[0100] Secondly, if the soldering of the gain medium is damaged when such a thermal mounting method is used, It is possible to receive it.
[0101] Thirdly, thermal aberrations that cause beam degradation can occur.
[0102] Fourthly, the thermal expansion of the laser gain medium may differ from the thermal expansion of its surroundings, thus affecting mechanical response. This can cause distortion and shattering of the force or gain medium.
[0103] For these reasons, the gain medium, in particular, needs to be thermally mounted to the cooling system. Typically, the gain medium generates 0.1 to 100 watts of heat, 1 mm². 2 ~40mm 2 Emitted from the surface To ensure that the temperature of the gain medium is kept below 150 degrees, the cooling system for the gain medium is... The thermal resistance must be less than 200 Kelvin per watt. From power inputs exceeding 10W For systems that typically transmit high power, the thermal resistance needs to be significantly lower. Yes, and in many cases, a thermal resistance of less than 0.05 Kelvin / watt is required.
[0104] The attachment of the cooling system surface to the gain medium depends on the expansion coefficient of the gain medium itself and the cooling system Typically, solder or This is done using a third material, such as an adhesive.
[0105] Such cooling systems typically include passive heatsinks, heatsinks with fans, and fans. A Peltier element or liquid cooling system connected to a heat sink with or without It could be any of the following: Alternatively, by active circulation based on a circulation pump, or by heat pipes. Alternatively, an independent liquid circulation cooling system using passive circulation can be used.
[0106] If the cooling system includes a heatsink with a fan, its thermal resistance is 0.1 degrees Kelvin. It must be less than one watt per watt.
[0107] If the cooling system is a passive heatsink, its thermal resistance is 0.3 degrees Kelvin per watt. It must be perfect.
[0108] If the cooling system uses a Peltier element, it is necessary to generate a temperature difference ΔT of at least 5 degrees. ru.
[0109] If the cooling system is an active liquid cooling system, it covers the entire range of thermal resistance mentioned here. - It must be possible to do so.
[0110] Passive heat sinks are preferable in systems designed for low cost and quiet operation. On the other hand, liquid cooling systems are preferred for high-power systems. Fan-assisted heating A typical system of a tosink or fluid pump has an electrical output of more than 1W, and It is used for transmitters with small volumes, approximately less than 1 liter.
[0111] The gain medium is typically driven by a driver, which in turn supplies power to the gain medium. However, that power is supplied as electrical power in the case of some semiconductor gain media, or other Semiconductor gain medium or DPSS system, or chemical or other form of energy In this case, it is given as light. The amount of power supplied by the driver depends on the operating conditions and the The radiation determines the small signal gain achieved. On the other hand, the saturation gain of the gain medium is generally This becomes a function of the material selected for the gain medium, and ultimately the radiation emitted from the laser. This becomes the irradiance. However, it is not necessarily a simple linear form. Such laser drivers Iba can have two or more operating states. One is used for power transmission, and the other is for targeting... It is used for other system functions such as exploration, setup, and information transmission. Important This is because the laser driver, under both operating conditions (regarding power and beam parameters), (i) To produce stable radiation. However, stable operation during power transmission is more important. ru.
[0112] To convert a light beam back into electricity so that useful power can be transmitted, an optical / power converter is used. In terms of type, a photovoltaic cell is required. Similar to lasers, the frequency of the beam used Appropriately sized photovoltaic cells are generally available as commercially available components. Therefore, a custom battery is needed. The bandwidth gap of the photovoltaic semiconductor is The bandwidth of the gain medium used is such that the beam frequency is efficiently absorbed by the semiconductor. It needs to be slightly smaller than the cap. Otherwise, the conversion efficiency will be very poor. On the other hand, if the bandwidth gap used is too small, a poorly efficient system can be achieved. Also, the conductors on the photovoltaic cell need to be tailored to the radiance of the beam being used. Yes, the higher the radiance, the thicker the required conductor.
[0113] The bandwidth gap of the laser gain medium must be in the range of 0.8 to 1.1 eV. The bandwidth gap of the photovoltaic power cell must be lower than that. Power cells typically have a bandwidth gap energy of approximately 60-80% of the total bandwidth gap energy divided by the electron charge. Since it generates a voltage of %, a single-junction battery tailored to the laser frequency is actually a system Assuming the required output power is a few watts, the voltage is typically very low, around 0.3-0.8V. This results in voltage and typically high current. Conductors on semiconductors carry the generated current (for example) It needs to be thick enough to transport without significant loss (more than 5%). Typically The series resistance of the conductors must be less than 1 ohm, and even better, less than 0.1 ohms. The heat generated needs to be efficiently extracted from the photovoltaic cell. This efficiency is generally related to temperature. It decreases along with it.
[0114] This combination of low voltage and high power is typical for charging portable devices. It cannot be easily converted to a high voltage of 3.3 or 5V. Furthermore, communication systems Some systems, such as those mentioned above, require voltages like -48V, 12V, or 3.8V. The system obtains a stable voltage at a level higher than the output voltage predicted from the photovoltaic cell. It needs to be supplied by. A typical way to increase the voltage of a photovoltaic cell is to directly supply the cell. This involves connecting in a series, for example, a "photovoltaic series array including P / N cells and N / P cells." MFAmsterdam et al., under the name "", have a U.S. patent of 3,370,986 It will be listed in issue number. This is while using almost the same amount of semiconductors without additional components. This configuration exhibits typical characteristics that result in high voltage, making it a commonly chosen solution.
[0115] However, this solution is 8kW / m 2 It has a high radiance of / steradians. This is not suitable for the system described in this application in which a laser is used. This is especially true for such systems. This is because lasers typically do not have a beam with a uniform shape. Furthermore, the shape of that beam... Since this can vary over time, the aiming accuracy may be more than what is desired to be optimal. It can be lower. In such situations, a compact and efficient way to illuminate all cells evenly is needed. Designing such a system is practically impossible. Photovoltaic cells connected in series are Therefore, the illumination will not be uniform, and thus the same current will not be generated. In practice, the voltage can be increased to the desired level, but the current can only be increased to the minimum current. The current drops to the level generated by the cells that produce the light, which are typically minimally lit. In such situations, efficiency is very poor. Therefore, an improved alternative is to increase the voltage. A method is needed.
[0116] One way to increase the voltage of a single cell is to charge a capacitor in parallel, and then, This method involves discharging in a series. This method yields good results for low currents, but for high currents... When the flow increases beyond a certain level, the switching time becomes a factor that affects efficiency. This is a contributing factor. Efficiency deteriorates as switching time increases.
[0117] Energy is converted to AC using a high-speed, low-resistance switching mechanism. In this case, the AC current is amplified using the coupled inductance and then converted back to AC. It is converted. The increased AC voltage is converted by a diode bridge and a capacitor or battery. Such a system can be converted to DC using an energy storage device. This has advantages when it is necessary to increase the voltage to more than 20 times the photocell voltage. Another advantage of this system is that switching can be done from the transmitter using a laser, so the receiver The cost and complexity of the device can be reduced. Such a system only requires a voltage of less than 10 times. If an increase is necessary, or if size and volume limitations are important for the application, In that case, there are disadvantages.
[0118] Here, we refer to Figure 13A, which shows an efficient and simple method of voltage conversion. Configuration of Figure 13A In this configuration, a single inductor is used to increase the voltage of the photovoltaic cell, with a low-resistance switch. It can be used in conjunction with a spooling mechanism and an energy storage device. (See Figure 13A) In this configuration, the square on the left is a photovoltaic cell, and switch S is a MOSFET, JFET, A low-resistance switch such as a BJT, IGBT, or pHEMT, where the inductance L is light Connected to the output of the electromotive force cell, capacitor C acts as an energy storage device.
[0119] For simplicity, the following description assumes the use of zero-resistance components. Resistive loss is Taking this into consideration makes the calculations complex, so it will be explained in a later section of this disclosure. The charging mechanism uses an inductor with two primary operating phases: a charging phase and a discharging phase. It circulates between phases. In the charging phase, the inductor closes switch S. This connects the photovoltaic power cell in parallel. During this phase, the inductor is connected in parallel with the photovoltaic power cell. It is charged by energy converted by power cells. Increase in inductor energy Ka is,
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[0120] During the discharge phase, the inductor, by opening switch S, generates photovoltaic energy. It is connected between the inductor and the load. During this phase, the output energy storage data from the inductor is released. The energy sent to the vice is the decrease in inductor energy.
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[0121] The energy transferred from the photovoltaic cell to the inductor during this phase is:
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[0122] In steady-state operation, the energy of the inductor at the end of the cycle is the same as the energy of the inductor. It was initially brought to Ikul
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[0123] However, in this system, the parasitic properties and other aspects of the components are transformed. This may have a significant impact on operation and efficiency, so allow for efficient operation of the system. Care must be taken to select and use the correct components. Let's consider each of the following elements one by one.
[0124] Inductor
[0125] 1. The inductance of an inductor defines the rate of change of the inductor current caused by the applied voltage. This is given by dI / dt = V / L, where dI / dt is the current change. This is the conversion ratio, where V is the voltage applied across the inductor and L is the inductance. In the context of current systems, V is determined by the gain medium in the transmitter. By selecting a gain medium, a change in photon energy is induced, and this This then governs the subsequent change in the photovoltaic bandwidth gap, and consequently, the change in the photovoltaic voltage. Therefore, this requires different inductors and / or switching frequencies. The speed is determined by the inductor current responding to the change in incident power from the transmitter via the optical / power converter. It must be fast enough to be able to do so, and power loss, input voltage ripple and output power It must be slow enough to avoid high-amplitude current ripples that contribute to pressure ripple. The optimal inductor value is such that the ripple current is 20% to 40% of the maximum predicted input current. It should be possible, but the system may be able to operate at 10% to 60%. Detailed analysis suggests that to achieve this objective, the inductor value measured in Henry units is required. L is limit
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[0126] To successfully integrate inductors into mobile clients, inductance is typical. It should be less than 10mH. This is required for charging mobile clients. An inductor suitable for the current being applied, and a suitable body for portable applications. This is because inductors with product limits typically fall well below this value. Also, 10n Inductors with inductances that are too small, such as H, are not suitable for switching in a system. High switching frequencies that severely limit the availability of other components such as We seek. The switching losses caused by such high frequencies are in the photovoltaic cell. The amount of power transmitted may be higher than that transmitted by other means.
[0127] 2. Series resistance R of the inductor parasitic This is to minimize conducted power loss. It needs to be as low as possible. Typically, a value that results in an efficiency decrease of less than 10% is selected. Therefore, the series resistance of an inductor, measured in ohms,
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[0128] 3. In a typical system, the series resistance of the inductor will be less than 10Ω. The saturation current is typically chosen to be higher than the predicted inductor peak current.
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[0129] 4. For reliable operation, the inductor should be designed to handle a current higher than the predicted maximum input current. It is rated for current. In order to extract power exceeding 10mW from a single-junction photovoltaic cell, The duct's rated current must be higher than 10mW / 0.8V = 12.5mA.
[0130] Switching mechanism
[0131] 1. A switching mechanism is usually made up of two or more devices. The first device, The in-switch, when conductive, sets the inductor to the charging phase. The second device is When a load or output energy storage device is connected to the inductor during the discharge phase, A diode (Figure 13A) or switch that has the function of disconnecting the connection during the charging phase. It could be either of the following.
[0132] 2. The switching mechanism is designed to minimize switching losses by using a low switching noise. Decapacitance
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[0133] 3. In a typical system, the switch node capacitance is less than 100nF and This exceeds 10 pF.
[0134] 4. In the switch node, connect the inductor to ground or the optical / power converter to the input The series resistance of the main switch connected to the duct is,
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[0135] Energy storage devices
[0136] 1. The energy storage device may be a capacitor, a battery, or both. .
[0137] 2. The energy storage device has a charge phase when the inductor is disconnected from the output. During the cycle, it is required to maintain the output voltage. The capacitance of the storage device is the same as the current. Based on the cutting frequency, laser power, and desired output ripple voltage,
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[0138] 3. Energy storage devices also supply power to the load while the optical path is temporarily interrupted. It can supply power. For the purpose of uninterrupted power supply, energy storage devices are less than [number missing]. Also, minimum operating output power (P OUT_MIN ) interruption time interval (T INT ) was multiplied
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[0139] In some cases, capacitors are used for energy storage in client applications. It will serve as a storage device. In such cases, the client application will These secondary energy storage devices (batteries conventionally used in mobile devices) ) can be designed without. Energy storage devices of the systems described herein This is sufficient to supply the client device with the necessary power until the next charging event. It is necessary to store a large amount of energy. In such cases, at least 0.5F and 10F A supercapacitor with a capacitance exceeding that can be used. That is, when the power requirements of the client device are low, or when the device is equipped with If the device has an independent energy storage device such as a battery, or if the device is power When there is no power supply and the capacitor does not need to operate, the capacitor used is typically 1F. Exceeding minutes. If a rechargeable battery is used as an energy storage device, the above charges apply. This is similar to the logic of Pasita, where the battery is used only as a voltage regulation means, but the charging events themselves If it is not used as a means of maintaining power supply to the client device during that time, The energy capacity of a battery is the amount of energy supplied during 100 cycles of the switch (typically... It is advantageous to set it up to 100 times (less than 0.1Wh) in terms of battery capacity. It is determined according to the load allocation and cost efficiency. On the other hand, the battery is cool between charging events. If it is also used to supply power to an Ant device, its capacity is at least, charging Energy required by the client device between events (cellular phone) It must be large enough to store (typically more than 0.1 Wh in some cases). Batteries also have volume limitations depending on the product they are intended for use in; that is, a certain volume limit. When a product battery with a product V is incorporated externally to the device, it typically... It is limited to several times the volume of the chair, i.e., up to 3V. As an example of this empirical rule, the volume is 100 The batteries used to power cc cellular phones are typically 300cc in volume. It is limited to less than 300Wh. Such batteries typically have a capacity of less than 300Wh due to the aforementioned limitations. The quantity differs.
[0140] The circuit in Figure 13A is not the only possible topology. Figure 13B shows... This shows different designs that can achieve similar performance characteristics. The components for Figure 13B The roles, constraints, and predicted values of the elements are the same as those listed for the circuit in Figure 13A. Yes, there is. The primary difference lies in the inversion of the positive and negative terminals of the output voltage.
[0141] In some applications, energy storage devices receive power It is preferable to place it inside the device in which it is intended to be used. Specifically, in this case, it refers to an application that is expected to operate for a short period and does not require a regulated voltage. In applications, even energy storage devices can be eliminated.
[0142] Points for adjustment
[0143] The power output of a photovoltaic cell depends on the incident light power and the load applied to it. Since the load conditions result in the maximum output power from the photovoltaic cell, the control mechanism of the voltage converter The load point needs to be adjusted. The control mechanism is for most conditions Is it designed to maintain a constant voltage between cell terminals, known as the maximum power operating point? Alternatively, by measuring the cell output power under arbitrary operating conditions, the optimal cell voltage can be sought. This allows us to track the point of maximum power operation. The first approach is simple, The second approach is even more power-efficient.
[0144] The generated laser beam needs to be directed towards the receiver. To the extent possible, a beam steering system will need to be used. Several beam steering sub-systems may be used. The system includes a movable mirror, movable lens, electrical / optical modulator, magnetic / optical modulator, and transmitter system. A set of motors that move the entire beam in one or more directions, or any other suitable beam deflection device. Includes chairs.
[0145] The beam steering system is used, most conveniently, to control the laser driver via a controller. It must be controlled by the same controller used.
[0146] The beam steering system is 8kW / m 2 / A beam exceeding steradians in a certain number of directions It is designed to be directed towards all of these.
[0147] The damage threshold of the beam steering system is set to withstand the beam's radiance. It is necessary.
[0148] For example, when a beam is focused on a mirror using a focusing mechanism with a numerical aperture of 0.5, The mirror is 8kW / m 2 At least 6.7 kW / m for a steradian beam 2 It needs to withstand that power density. When a high-radiance beam is used, the mirror will It is necessary to select a model that has a high damage threshold in response to this.
[0149] Figure 14 shows 8 kW / m 2 / Per square meter when a steradian beam is in focus The power reflected by the mirror is shown as a function of the numerical aperture. A beam with high radiance When used, the power reflected by the mirror increases in a linear manner in response.
[0150] Because the beam is far from uniform, it can sometimes have a radiance 10 times greater than the beam average. A "hot spot" may be generated.
[0151] Therefore, the mirror is used to determine the actual beam radiance and numerical aperture of the focusing mechanism on the mirror. The combined scale is at least the same size as shown in Figure 14, preferably at least Both need to have a damage threshold 10 times higher.
[0152] Typically, the receiver is located near the photovoltaic cell and between the photovoltaic cell and the transmitter. A designated optical front exists. The beam enters the receiver through this optical front, and this optical front is This is necessary to protect the typically delicate structure of photovoltaic cells, and is often required for power reception. The signaling device is integrated into the external design of the device. The front panel is Corning's Gorilla Glass. It has a protective film that prevents scratches, such as S (registered trademark), or is good at preventing scratches. It is treated to withstand fingerprints and dust. The surface is also treated to withstand stains such as fingerprints and dust. Light that has been treated or reflected to reduce bell or reduce optical effects. An anti-reflective coating can be applied to reduce the level of reflective properties. The front surface of the photovoltaic cell may also be coated. It can be done. In some cases, the front becomes part of the structure of the photovoltaic cell itself, and It is coated onto the photovoltaic cell.
[0153] In some situations, the amount of reflection from the surface is reduced by selecting an anti-reflective coating with very low reflectivity. By doing so, the risk can be reduced to below the safety threshold. In the event that spilled liquid or finger If the film is contaminated or covered by any of the markings, the anti-reflective film will reduce its reflectivity. The effect is lost, and typically 3-4% of the incident light is reflected in the direction of the mis-controlled beam. When reflection occurs in a divergent manner, the power density will soon decrease to a safe level. However, if the reflection is focused, the power density can increase to dangerous levels. For this reason, the ROC (radius of curvature) of such surface It is important to ensure that the value does not fall below a predetermined value at any point. This is crucial. Generally, reflection from a surface is intended to be limited to only a small portion of the incident light. Regardless of the properties or shape of the curvature of the surface, any The risk of unintended beam reflection is reduced. The level of reflected light can be variable. Even with approximately 4% reflection from an untreated glass surface, a layer of foreign contaminants on the surface can still cause problems. This is because it can increase if it results in increased reflectivity. However, the opposite is true. The radiation is not expected to exceed 20%, and the reflectance is 0.1% or considerably lower. However, as is the case with typical AR-coated glass, it is generally about 4% of the untreated glass. It becomes less than. Therefore, the surface is considered to have the property of reflecting a small portion of the incident light. This is described in the disclosure and as described in the claims. This specification refers to 20% of the incident light. Less than is generally used to mean less than 4% of untreated glass.
[0154] Here, even for a small portion of the incident light that can be reflected from the surface, the above-mentioned dangerous reflection is Refer to Figures 15A-15C, which schematically illustrate methods for avoiding this issue. Figure 15A shows a concave surface. Figure 15B shows the situation where the surface is convex, and Figure 15C shows the situation where the surface is diffuse. This shows that in Figure 15A, at least 8 kW / m 2 It has a radiance of / steradians. The incident beam 110 is directed towards the photovoltaic cell 112 and can become the front of the photovoltaic cell. It penetrates the front surface 111. The front surface 111 reflects a certain amount of the beam 110, and a certain amount is reflected from the surface. A focused beam 113 is generated with a focal point 114 at a distance. To ensure that it does not pose any danger to skin or other objects, the curvature of surface 111 The radius (ROC) is set so that the beam is focused by a low numerical aperture, as shown in Figure 15A. It must be done, or as shown in Figure 15B, as the focus is blurred, or Figure It must be diffused as in 15C. These limitations must be achieved. Therefore, as shown in Figure 15A, the surface becomes concave when viewed from the transmitter toward the photovoltaic cell. In that case, the ROC must be greater than 1 cm and typically exceed 0.5 W. If a high-power optical system is used, it must be larger than 5 cm. Alternative Furthermore, the ROC of the surface can be negative, as shown in Figure 15B, but ROC is 0 It must not be within a range of ~1 cm. These restrictions prevent the reflected light beam from becoming scalable. The point is associated with a virtual, i.e., divergent / reflective beam, or the focal point is less in front of the surface. It is guaranteed that it will be either at 1 cm or at the same time. As a result, the focal point will cause The suction is significantly reduced. The surface also results in a small diffuse surface, as shown in Figure 15C. It can have a large number of regions with small curvature. This is a dangerous focal point squirrel. It helps to significantly reduce the curvature of each subsection of the surface. The diameter can be less than 1 cm, which does not produce a focal point. Furthermore, the surface is divided into numerous zones. When divided, each zone may have a small curvature.
[0155] To ensure safe operation, the system also ensures that the power beam is not blocked by the photovoltaic cell. The power beam can be directed towards the photovoltaic cell to prevent it from being aimed at that dangerous area. It is necessary to do so. To achieve this, the detector provides the receiver with an indication of the beam collision. It is necessary to position it so that it can be positioned. Such detectors are typically positioned in front of the receiver. However, a configuration in which such a detector is placed on the transmitter is also possible. In this case, the detector is the receiver It is necessary to respond to phenomena caused by the beam impact on the transmitter. Such transmitter-related systems The beam acquires images and receives beams from the receiver, including barcodes printed on the receiver. This may include processing of light information such as reflection. As a result, the transmitter can determine the illumination pattern of the barcode. It can detect one or more retroreflectors or their arrays or patterns. The reflection from the receiver is positioned, and such reflection is used for image processing, back reflection measurement, or This can be detected in the transmitter by measuring the coherence effect of the reflection. The detector is a current or voltage sensor positioned in the receiver, or in the receiver or transmitter. An imaging device that may be present in either a photodiode, transmitter, or receiver. This can be done. A retroreflector located near the photovoltaic cell is also a retroreflector in the transmitter. It can be used in combination with an additional detector that detects light reflected from the retroreflector. .
[0156] When the detector detects a beam of light colliding with the photovoltaic cell, it follows the system controller It transmits a signal. If the detector is in the receiver, such signaling is RF, IR, and visible. Wireless communication using light, UV, beam modulation, TCP / IP, or a communication channel that can be sound. This can be done by [method]. The system controller is usually located at the transmitter, but from the transmitter It may be placed in the main control unit, which may also exist on a computer network. Upon receiving the signal, the controller responds by doing at least one of the following: (a) Laser (b) Change the driver's state. The direction the beam is directed, and the speed at which that direction is changed. This modifies the operating characteristics of the beam steering system, such as by a certain degree.
[0157] Here, refer to Figure 16, a schematic diagram showing a detailed description of the complete system. The system includes a transmitter 21 and a receiver 22. Generally, the transmitter and receiver are located far apart from each other. They are arranged in such a way, but for convenience, Figure 16 shows them as being close to each other. Unit 15 transfers power from transmitter 21 to receiver 22.
[0158] In the receiver 22, the front surface 7 reflects a small portion of the incident beam 15 as a reflected beam 16. On the other hand, the beam is diffused, or a virtual focus is created behind the front 7, or the surface 7 To create a real focus at least 1 cm in front of it. Through at least partially transparent surface 7 After transmission, beam 15 collides with the optical / power converter 1.
[0159] The optical / power converter 1 is enclosed in a package which may have a front window that can be a surface 7 or a separate window. This can also be done at the interface with air or the surrounding adhesive or glass. It may be coated to have an external surface adapted to function as such. Typical In this configuration, the optical / power converter 1 typically has a junction where a conductor is deposited on a semiconductor layer. It is possible. In many embodiments, the surface 7 is coated with one of these semiconductor layers. or one of the external surfaces.
[0160] The signaling detector 8 indicates that the beam 15 is colliding with the photovoltaic cell 1, and This information is transmitted to the controller 13 located at the transmitter 21 in this example system. Your signal is transmitted via link 23 to the detector 24 in the transmitter.
[0161] Power converter 1 has a band gap E8 and typically has a voltage of 0.35~1.1V. However, even higher voltages can be achieved by using multi-junction photovoltaic cells. The current flows from the photovoltaic cell 1 through low-resistance conductors 2a and 2b to the inductor 3. Inductor 3 stores a portion of the energy that flows through it in a magnetic field.
[0162] The automatic switch 4 is typically a MOSFET connected to a control circuit (not shown in Figure 16). It is a transistor, and it switches between alternating states, so the current is in the first part of time. It is permitted to flow through ductor 3 to ground, during the second part of the time The inductor radiates its stored magnetic energy as a current with a higher voltage than that of a photovoltaic cell. It is permissible to do so. The current passes through diode 5, and then the power can be used. The load will then proceed to a maximum of 6.
[0163] Automatic switch 4 is controlled by a fixed frequency, or by a transmitter or client load It operates with a variable frequency and / or duty cycle and / or waveform controlled by or based on the current, voltage or temperature in the load, or the current in the automatic switch 4, Based on voltage or temperature, or based on current, voltage or temperature radiated by the optical / power converter 1 It can be determined based on, or on, several other indicators regarding the state of the system.
[0164] The receiver can be connected directly to the load 6, as shown in Figure 16. Alternatively, Power 6 is located outside the receiver, or is connected to another power-consuming device such as a cell phone or other power-consuming device. This is a single device, and it uses USB / Micro USB / Lightning (registered trademark) / USB Type It can be connected using a socket like a C socket.
[0165] In most cases, an energy storage device such as a capacitor or battery connected in parallel to the load 6. There are also storage devices, or load 6 is an energy storage device such as a capacitor or battery. This may include devices.
[0166] Transmitter 21 generates a beam 15 and directs it towards receiver 22. In the first operating mode. The transmitter 21 searches for the presence of the receiver 22. This is done using a scan beam, and The receiver is detected using communication means such as RF, light, IR light, UV light, or sound. By means of, or retroreflectors or retroreflective structures, barcodes, high-contrast patterns Using a camera that detects the receiver's visual indicator, such as a light or other visual indicator. This is done using [a specific method / tool]. Once the approximate location is found, beam 15 is typically sent at low power, and [another specific method / tool] is used. The immediate area around the signaling device 22 is scanned. During this scan, the beam 15 generates photovoltaic power. The beam 15 collides with the photovoltaic cell 1. When the beam 15 collides with the photovoltaic cell 1, the detector 8 detects it. And, accordingly, a signal is sent to the controller 13.
[0167] The controller 13 commands the laser driver 12 to change the power P and input it to the gain medium 11. This means, and / or commanding the mirror 14 to change either its scan speed or direction. Change the beam's position, direct it to that location or hold it there, and change the scan step speed. The gain medium 11 responds to such signal by either or both of the following means. When received from the laser power supply 12, the small signal gain, that is, the gain of a single photon, is determined by the gain medium. The gain received when crossing the gain medium, where no other photons are simultaneously crossing the gain medium. , changes. Photons directed in the direction between the rear mirror 10 and the output coupler 9 become the gain medium. As it passes through 11, more photons are emitted in the same direction as beam 15, and backward mining Optical resonance occurs between the Rah 10 and the output coupler 9.
[0168] The output coupler 9 partially passes through a mirror having reflectance R, at 6940 cm². -1 ni oke The first harmonic of CH absorption and 8130cm -1 The space between the second harmonic of CH absorption in At least part of the culvert operates, and typically, alternating layers of materials with different refractive indices are typically This is a multilayer dielectric deposited on a substrate that will be the surface of the gain medium 11, which is glass, plastic, or a substrate. This becomes a semiconductor film. Alternatively, Fresnel reflection provides a signal gain that is sufficiently small for the gain medium. It can be used if it has a sufficiently high refractive index. Standard gold A genuine mirror can also be used. If the gain medium is a semiconductor or fiber amplifier, then a bra A dog reflector can also be used. The output coupler 9 also transmits one part of the light and extracts the other part of the light from the wave traveling forward inside the resonator, but typically a third part is also extracted from the wave propagating backward inside the resonator, and can consist of a high-reflectivity mirror combined with a beam extractor such as a semitransparent optical component .
[0169] The rear reflector 10 should be a high-reflectivity mirror, but a small amount of light leaks backward and is used for monitoring rings or other purposes and operates at least in part of the spectrum between the first overtone of the C-H absorption at 6940 cm -1 and the second overtone of the C-H absorption at 81 30 cm -1 . Typically, it can be constructed from alternating layers of different refractive index materials deposited on a substrate, which is usually glass, metal or plastic. Alternatively, if the gain medium is small enough <000168ak82>to provide sufficient signal gain, Fresnel reflection can also be used. Standard metal mirrors can also be used. When the gain medium is a semiconductor or fiber amplifier , a Bragg reflector can also be used. <{
[0170] The gain medium 11 amplifies the radiation between the first overtone of the C-H absorption at 6940 cm -1 and the second overtone of the C-H absorption at 8130 cm -1 . However, it does not necessarily cover the entire spectral range. This can send a small-signal gain larger than the loss caused by the output coupler 9 when excited by the laser driver 12 with power P . Its area, field of view, and damage threshold are at least 8 kW / m / steradian / (1 2 It needs to be large enough to maintain the beam of -R), where R is the output coupler 9 This is the reflectance of a transparent host material doped with Nd ions, ranging from 0.8 to 1.1. A semiconductor material having an eV bandgap, or a material that simulates radiation in the said spectral range. It may consist of other structures that can be used. The gain medium 11 exits from the back reflector 10. Positioned in the optical line of sight to the force coupler 9, and consequently reflected by the rear reflector 10 Resonance of radiation is permitted between the back reflector 10 and the output coupler 9 via the gain medium 11. ru.
[0171] A typical implementation where the gain medium 11 is a semiconductor with a bandgap of 0.8 to 1.1 eV. For this purpose, it is preferable to attach it to a thermal extraction device, and the laser driver 12 It can be excited electrically or optically.
[0172] The gain medium 11 is Nd-doped YAG, YVO4, GGG, or glass yogurt. In a typical implementation where the host is transparent, such as ceramics, the gain in this case is The medium 11 is 9400 cm² from the resonance between the rear mirror 10 and the output coupler 9. -1 nearby It is preferable to use a filter and optical communication to extract the radiation.
[0173] The beam steering device 14 is shown to be controlled by the controller 13. 15 can be deflected in multiple directions. Its area can be tilted up to the maximum operating tilt angle. Even so, it must be large enough to encompass virtually all of beam 15. No. Let's take a simple 2D example. Beam 15 is collimated to a 5mm diameter (1 / e 2 It is a Gaussian beam of diameter () and the beam steering device is a single beam centered on the beam center. If it is a rounded gimbal mirror, and the maximum tilt required for the mirror is 30 degrees And, assuming that the beam steering device 14 does not have any other openings, the mirror is If it has a similar 5 mm diameter as the beam, then approximately in the normal incidence of the beam While this results in a 13% loss, at a 60-degree tilt angle, the loss is approximately 60%. This is because the system This severely impairs the system's performance. This power loss is illustrated in the graph in Figure 17.
[0174] At the start of operation, the controller 13 instructs the laser driver 12 and mirror 14 to perform a search operation. This commands the receiver 22 by operating the laser driver 12 in the first state. This is done by directing beam 15 in a general direction where it is likely to be discovered. Example For example, if the transmitter is mounted in the corner of the ceiling of a room, the scan will be downwards and within the room. This takes place between two adjacent walls. The beam 15 is sent to the receiver 22 which contains the optical / power converter 1. If it hits, the detector 8 sends a signal to, for example, the controller 13. Unless such a signal is received The controller 13 then directs the beam 15 in a different direction relative to the beam steering unit 14 to search for the receiver. The controller commands the beam to perform the following action. When such a signal is received from the detector 8, the controller 13 controls the beam. The rudder unit 14 is instructed to stop or slow down the scan and lock onto the receiver. - Instructs the driver 12 to increase power radiation. Alternatively, the controller 13 receives The position of container 22 can be recognized, allowing you to return to it in later stages.
[0175] When the laser driver 12 increases its power radiation, the small-signal gain of the gain medium 11 increases. As a result, beam 15 carries a lot of power and power transmission begins. Detector 8 detects When a power loss greater than the threshold is detected, the controller 13 typically directs the laser driver 12 to... This state is changed by reducing power to maintain the required safety level. The command is issued accordingly. The threshold is predetermined or dynamically set, and is typically the maximum permissible exposure. It is at a level that represents a significant portion of the level, and is typically larger than the system noise figure. These conditions mean that beam 15 is no longer precisely directed towards the optical / power converter 1. This suggests that an object entered the beam's path or that a malfunction occurred. Other indicators of safe operation, such as those displayed via the user interface or API, will be used. User indications regarding the security of transmissions that may be transmitted, or safe actions from a second security system. If a signal is present, the controller increases power to the laser to compensate for power loss. The controller 13 can also command the beam steering assembly 14 to do the same. You can also instruct it to perform a search operation.
[0176] The search process involves two distinct stages. First, the search is conducted to find visual patterns. Using a capable camera, find the retroreflector, find a high-contrast image, and then the receiver To obtain their response signals, or to obtain other displays, or the scan feature section of the beam steering unit 14 By using this, a coarse search is performed. In this way, potential receivers can be found. A list of locations can be generated. The second stage is a detailed search. Here, The steering mirror 14 receives a signal from the detector 8 indicating that the beam 15 is colliding with the light / power converter 1. The beam 15 is directed towards a small area until it is sent.
[0177] Here, Figure 18 shows an example of a cooling system for the gain medium 11 of the system in Figure 16. See reference. Reflectors 9 and 10 are shown as separate optical elements, but one or both of them It should be understood that, in order to simplify the system, the gain medium can be directly coated. The gain medium 11 converts the power received from the laser driver 12 into both heat and photons. Conversely, if the gain medium is heated to a temperature above a certain level, the system performance typically deteriorates. For this reason, a thermally conductive solder with low thermal resistance is preferred for the gain medium 11. It is attached to the heat sink 34 using the binder 33. The binder 33 is a conductive adhesive. This is also good. The binder 33 is the thermal expansion coefficient of the gain medium 11 and the thermal expansion coefficient of the heat sink 34. It may have a coefficient of thermal expansion between [values]. The heat sink 34 is typically a metal low thermal resistance heat sink. Fins that increase surface area, or fans or liquid pumps 35, are often used as a base. An external fluid pump system is installed.
[0178] Refer to Figure 19 here. This shows a detailed description of the system in Figure 16, but is not described in this application. A safety system 31 configured and operable according to the method and system described herein is further incorporated. This is a schematic diagram. Figure 19 shows a separate module to illustrate the additional inputs that will be provided. As shown, the safety system can be incorporated into the controller 13, which is generally described Thus, the claims are defined as follows. As described above, the system consists of a transmitter 21 and a receiver Includes transmitter 22. Generally, the transmitter and receiver are placed far apart from each other, but for convenience, As shown in Figure 19, they are approaching each other. Beam 15 is from transmitter 21 to receiver 22. To transfer electricity.
[0179] In the receiver 22, the front surface 7 reflects a small portion of the incident beam 15 as a reflected beam 16. On the other hand, the beam is diffused, or a virtual focus is created behind the front 7, or the surface 7 To create a real focus at least 1 cm in front of it. Through at least partially transparent surface 7 After transmission, the beam 15 has a thickness T and a constant absorption coefficient for the light beam 15. It collides with an optical / power converter 1 having a semiconductor layer. The thickness of the layer is measured in centimeters. Depending on the beam design wavelength, the semiconductor layer is further detailed in Figure 20 below. The absorption coefficient of the light beam must be set to 0.02 times the reciprocal of the absorption coefficient.
[0180] The optical / power converter 1 is enclosed in a package which may have a front window that can be a surface 7 or a separate window. This can also be done at the interface with air or the surrounding adhesive or glass. It may be coated to have an external surface adapted to function as such. Typical In its configuration, the optical / power converter 1 typically has a junction of semiconductor layers on which conductors are deposited. It is possible. In many embodiments, the surface 7 is coated with one of these semiconductor layers. or one of the external surfaces.
[0181] The signaling detector 8 indicates that the beam 15 is colliding with the photovoltaic cell 1, and The information is transmitted to the controller 13, and in many cases, the received power, received optical power, and identification information are transmitted. The receiver's temperature and photovoltaic power, as well as control information from client devices, are also collected. It also transmits other data, such as relayed information. In this example, the system controller 13 It is located on transmitter 21, but may be located remotely from there. The control signal is on link 2 The signal is transmitted to the transmitter's detector 24 via step 3.
[0182] The safety system 31 receives information from various sources, which are detailed below in Figure 21. In particular, from a small portion of the coupled beam 15 from the beam coupler 32, and from the signal Information is transmitted from the power detector 8, normally via the data channel between the power receiver and the power transmitter. The safety system 31 receives the signal and outputs a safety indicator to the control unit 13.
[0183] Power converter 1 has a band gap E8 and typically has a voltage of 0.35~1.1V. However, even higher voltages can be achieved by using multi-junction photovoltaic cells. The current flows from the photovoltaic cell 1 through low-resistance conductors 2a and 2b to the inductor 3. Inductor 3 stores a portion of the energy that flows through it in a magnetic field.
[0184] The automatic switch 4 is typically a MOSFET connected to a control circuit (not shown in Figure 19). It is a transistor, and it switches between alternating states, so the current is in the first part of time. It is permitted to flow through ductor 3 to ground, during the second part of the time The inductor radiates its stored magnetic energy as a current with a higher voltage than that of a photovoltaic cell. It is permissible to do so. The current passes through diode 5, and then the power can be used. The load will then proceed to a maximum of 6.
[0185] Automatic switch 4 is controlled by a fixed frequency, or by a transmitter or client load It operates with a variable frequency and / or duty cycle and / or waveform controlled by, and This is based on the current, voltage, or temperature at the load, or the current, voltage, or temperature at the automatic switch 4. This is based on temperature, or based on the current, voltage, or temperature radiated by the optical / power converter 1. Alternatively, it can be determined based on several other indicators regarding the system's state.
[0186] The receiver can be connected directly to the load 6, as shown in Figure 16. Alternatively, Power 6 is located outside the receiver, or is connected to another power-consuming device such as a cell phone or other power-consuming device. This is a single device, and it uses USB / Micro USB / Lightning (registered trademark) / USB Type It can be connected using a socket like a C. The receiver is typically the receiver This further includes load ballast used to dissipate excess energy from the container. This may not be necessary for all clients.
[0187] In most cases, an energy storage device such as a capacitor or battery connected in parallel to the load 6. There are also storage devices, or load 6 is an energy storage device such as a capacitor or battery. This may include devices.
[0188] Transmitter 21 generates a beam 15 and directs it towards receiver 22. In the first operating mode. The transmitter 21 searches for the presence of the receiver 22. This is done using a scan beam, and The receiver is detected using communication means such as RF, light, IR light, UV light, or sound. By means of, or retroreflectors or retroreflective structures, barcodes, high-contrast patterns Using a camera that detects the receiver's visual indicator, such as a light or other visual indicator. This is done using [a specific method / tool]. Once the approximate location is found, beam 15 is typically sent at low power, and [another specific method / tool] is used. The immediate area around the signaling device 22 is scanned. During this scan, the beam 15 generates photovoltaic power. The beam needs to collide with the photovoltaic cell 1. When the beam 15 collides with the photovoltaic cell 1, the detector 8 It detects this and sends a signal to the controller 13 accordingly.
[0189] The controller 13 commands the laser driver 12 to change the power P and input it to the gain medium 11. This means, and / or commanding the mirror 14 to change either its scan speed or direction. Change the beam's position, direct it to that location or hold it there, and change the scan step speed. The gain medium 11 responds to such signal by either or both of the following means. When received from the laser power supply 12, the small signal gain, that is, the gain of a single photon, is determined by the gain medium. The gain received when crossing the medium, assuming no other photons simultaneously cross the medium. , changes. Photons directed in the direction between the rear mirror 10 and the output coupler 9 become the gain medium. As it passes through 11, more photons are emitted in the same direction as beam 15, and backward mining Optical resonance occurs between the Rah 10 and the output coupler 9.
[0190] The output coupler 9 partially passes through a mirror having reflectance R, at 6940 cm². -1 ni oke The first harmonic of CH absorption and 8130cm -1 The space between the second harmonic of CH absorption in At least part of the culvert operates, and typically, alternating layers of materials with different refractive indices are typically This is a multilayer dielectric deposited on a substrate that will be the surface of the gain medium 11, which is glass, plastic, or a substrate. This becomes a semiconductor film. Alternatively, Fresnel reflection provides a signal gain that is sufficiently small for the gain medium. It can be used if it has a sufficiently high refractive index. Standard gold A genuine mirror can also be used. If the gain medium is a semiconductor or fiber amplifier, then a bra A dog reflector can also be used. The output coupler 9 also transmits one part of the light and extracts the other part of the light from the wave traveling forward inside the resonator. Typically, However, a third part can also be extracted from the wave propagating backward inside the resonator, typically consisting of a highly reflective mirror combined with a beam extractor such as a semi-transparent optical component. The rear reflector 10 should be a highly reflective mirror, but a small amount of light is allowed to leak backward from it and can be used for monitoring or other purposes. These optical features need to operate in at least a part of the spectrum between the first overtone of the C-H absorption at 6940 cm
[0191] and the second overtone of the C-H absorption at 8130 cm Typically, it can be constructed from alternating layers of materials with different refractive indices deposited on a substrate, usually glass, metal or plastic. Alternatively, if the gain medium can provide a sufficiently small signal gain, Fresnel reflection can also be used. Standard metal mirrors can also be used. If the gain medium is a semiconductor or fiber amplifier, a Bragg reflector can also be used. -1 -1 -1 -H absorption at 8130 cm It needs to operate in at least a part of the spectrum between the first overtone of the C-H absorption at 6940 cm Typically, it can be constructed from alternating layers of materials with different refractive indices deposited on a substrate, usually glass, metal or plastic. Alternatively, if the gain medium can provide a sufficiently small signal gain, Fresnel reflection can also be used. Standard metal mirrors can also be used. If the gain medium is a semiconductor or fiber amplifier, a Bragg reflector can also be used. A dog reflector can also be used.
[0192] -1 The gain medium 11 amplifies the radiation between the first overtone of the C-H absorption at 6940 cm -1 and the second overtone of the C-H absorption at 8130 cm It needs to be able to send a small signal gain larger than the loss caused by the output coupler 9 when excited by the laser driver 12 with power P. Its area, field of view, and damage threshold are at least 8 kW / m2 / steradian / (1 It needs to be large enough to maintain the beam of -R), where R is the output coupler 9 This is the reflectance of a transparent host material doped with Nd ions, ranging from 0.8 to 1.1. A semiconductor material having an eV bandgap, or a material that simulates radiation in the said spectral range. It may consist of other structures that can be used. The gain medium 11 exits from the back reflector 10. Positioned in the optical line of sight to the force coupler 9, and consequently reflected by the rear reflector 10 Resonance of radiation is permitted between the back reflector 10 and the output coupler 9 via the gain medium 11. ru.
[0193] A typical implementation where the gain medium 11 is a semiconductor with a bandgap of 0.8 to 1.1 eV. For this purpose, it is preferable to attach it to a thermal extraction device, and the laser driver 12 It can be excited electrically or optically.
[0194] The gain medium 11 is Nd-doped YAG, YVO4, GGG, or glass yogurt. In a typical implementation where the host is transparent, such as ceramics, the gain in this case is The medium 11 is 9400 cm² from the resonant radiation between the rear mirror 10 and the output coupler 9. -1 It is preferable to use a filter and optical communication to extract radiation from the vicinity.
[0195] The beam steering device 14 is shown to be controlled by the controller 13. 15 can be deflected in multiple directions. Its area can be tilted up to the maximum operating tilt angle. Even so, it must be large enough to encompass virtually all of beam 15. No. Let's take a simple 2D example. Beam 15 is collimated to a 5mm diameter (1 / e2 It is a Gaussian beam of diameter () and the beam steering device is a single beam centered on the beam center. If it is a rounded gimbal mirror, and the maximum tilt required for the mirror is 30 degrees And, assuming that the beam steering device 14 does not have any other openings, the mirror is If it has a similar 5 mm diameter as the beam, then approximately in the normal incidence of the beam While this results in a 13% loss, at a 60-degree tilt angle, the loss is approximately 60%. This is because the system This severely impairs the system's performance. This power loss is shown in the graph in Figure 17, and also in Figure 2 below. Examples are given in 2 and 23.
[0196] At the start of operation, the controller 13 instructs the laser driver 12 and mirror 14 to perform a search operation. This commands the receiver 22 by operating the laser driver 12 in the first state. This is done by directing beam 15 in a general direction where it is likely to be discovered. Example For example, if the transmitter is mounted in the corner of the ceiling of the room, the scan will be downward, and This takes place between two adjacent walls in the room. The beam is directed to the receiver 22, which contains the optical / power converter 1. If 15 is hit, the detector 8 sends a signal to, for example, the controller 13. If such a signal is not received As far as is concerned, the controller 13 directs the beam 15 in a different direction relative to the beam steering unit 14 and the receiver It commands to search. When such a signal is received from detector 8, controller 13 will beep. The steering unit 14 is instructed to stop or slow down the scan and lock onto the receiver. The controller 13 then indicates that the safety system 31 is operating safely. Waiting for the signal to be generated, once such a safety signal is received from the safety system 31 The controller 13 instructs the laser driver 12 to increase its power radiation. Alternatively, the controller 13 can recognize the position of the receiver 22 and then in a later stage... It is possible to return to the previous state. This can be done even if no safety signal is present.
[0197] When the laser driver 12 increases its power radiation, the small-signal gain of the gain medium 11 increases. As a result, beam 15 carries a lot of power and power transmission begins. Detector 8 remains constant. When a power loss greater than a threshold is detected, the safety system 31 controls the situation. The status can be reported to the device 31. The controller 31 usually reports this status to the laser driver 12. The command is to modify the system by reducing power to maintain the required level of safety. It is necessary to do so. Such power loss thresholds are predetermined or set dynamically, and are typically the most It is at a level that represents a significant portion of the high-permissibility exposure levels, and is typically the system noise figure. It is larger than this. The condition is that the beam 15 is no longer precisely directed towards the optical / power converter 1. This means that the beam is not in the path of the beam, or that some object has entered the beam's path, or that a malfunction has occurred. This suggests that other indicators of safe operation, such as the user interface or API, may be used. User indications regarding the security of transmissions that may be displayed, or security information from a second security system. If the "All Operations" indicator is present, the controller increases power to the laser to compensate for power loss. The controller 13 can also instruct the beam steering assembly 14 to do the same. Conversely, it is also possible to instruct the system to perform the search operation again.
[0198] The search process involves two distinct stages. First, the search is conducted to find visual patterns. Using a capable camera, find retroreflectors, and obtain high-contrast images (LED Or to seek a response signal from the receiver (such as a flashing light from another light source) or to seek another indication. A rough search is performed, or the rough search is performed on the scan feature area of the beam steering unit 14. This may be done by using the following: the potential locations where the receiver may be found. It is possible to generate a strike. The second stage is a detailed search. Here, beam steering mechanism The radar 14 receives a signal from the detector 8 indicating that the beam 15 is colliding with the optical / power converter 1. So, keep beam 15 pointed at a small area.
[0199] Here, in Figures 16 and 19, the schematic diagram of the optical / power converter labeled as element 1 is shown. Refer to Figure 20. The beam 15 is photovoltaically connected to the heat removal system 107. The beam 15 collides with the force cell 106. The beam 15 is absorbed by the absorption layer 108, and the current flows through the conductor 111. This is caused by the current being collected by the bus. Absorption layer 108 The absorbed light power is typically converted into electricity and heat. The electricity is then converted into conductor 111 and lower electric While some energy is transferred through the poles, most of the thermal energy is exhausted through the cooling system 107. It is removed. The conductor 111 casts a shadow on the absorption layer 108, thus reducing its efficiency. For example, conductor 111 is 3 × 10 -6 Materials having electrical resistivity less than ohms* meters It needs to be made from a highly conductive material. Such a conductor must be meter thick, i.e., At least (0.034*Pρ) / (V 2 It has been shown that it needs to have a thickness of *χ)m. Here, P is the power absorbed by the photovoltaic unit, which is measured in watts. ρ is the specific electrical resistivity of the conductor. V is the amount of energy released by the photovoltaic cell at the point of maximum power. The voltage produced is χ, and χ is the ratio of the area of the absorption layer covered by the conductor.
[0200] The absorption layer also needs to be thick enough to absorb most of the incoming beam 15. Yes. To do this, the thickness of the absorption layer 108, measured in meters, is at least 0 0.02 / μ 10 It is necessary to do so. Here, μ 10 This is a decimal system measured in units of 1 / m. This is the damping coefficient.
[0201] Here, refer to Figure 21, which shows a block diagram of the safety system 31 in Figure 19. Mu 31 is in a situation where the safety system is not an integrated part of the controller 13, or the safety If the system is located within an external control unit, input from various sensors and subsystems It receives the force and transmits the output to the controller 13. The safety system 13 also receives these various signals. It can also occasionally receive inputs from sensors and subsystems. Such inputs are beam It is necessary to monitor the wavelength first and estimate the safety limits associated with the beam. It can be a wavelength sensor 407 that provides information. This can also be a shape, M 2 , Symmetry, polarity, power, divergence, coherence, and related parameters of the beam. Information from a beam analyzer (401) that monitors the characteristics of the beam, such as other information. It can also receive information measured by an external subsystem. , received via RF link 402. Transmitter, receiver and various components in the surrounding area The temperature of the component can be measured by the temperature sensor 403. Images from camera 404, which can be visual, thermal, IR, or UV, or the power of the beam, are measured at various positions. Images from the power meter 406 measuring at the location can be received. In many cases The primary sensor connected to the safety system 31 crosses the beam path or its surroundings. Alternatively, it may be used as an intrusion sensor (405) that monitors the beam to detect approaching foreign objects. It also receives input from other sensors such as current, voltage, smoke, humidity, and other environmental sensors. It can also be trusted. Upon receiving these inputs, or at a pre-scheduled time, The safety system 31 evaluates the potential for a safety violation, and if the evaluation exceeds a predetermined threshold, A notification is sent to the controller 13.
[0202] Here is a diagram showing a beam deflected by mirrors rotating on one or more gimbal axes. See 22. The beam 15 strikes the mirror 332 which rotates around two axes in two dimensions. It strikes. The beam 15 forms a spot 333 on the mirror 332 and is deflected in different directions. The importance of selecting the appropriate center of rotation and mirror dimensions is illustrated in Figure 23. This becomes clear. In Figure 23, the mirror 332 is rotated here, Here, frame 15 is deflected to a larger angle compared to Figure 22. Increased angle Therefore, spot 333 here projects a length longer than the effective length of mirror 332 onto the mirror surface. It is formed on the surface. As a result, a significant portion of the beam 15 is labeled as 333A. The part that spills out from around mirror 332. This spillage reduces the brightness of beam 15. This is achieved by both reducing power and trimming the edges. In most cases, beam quality degrades at long distances. Typically, the beam diameter is... If it decreases in the near field or in the near field image, it increases in the far field. To achieve the smallest possible system that operates with relatively high efficiency, Maintaining high brightness is crucial. This is important across all angles within the system's field of view. This can be achieved by reducing the brightness loss experienced by beam 15 during the rotation of the mirror. The core is the weighted average of the beam intensity, the cross-sectional diameter of the beam at a constant intensity, and the ellipse through which the beam passes. The mirror is positioned to be substantially close to the center of the beam, as measured by one of the centers of the circular aperture. This can be achieved by attaching it. Note that, in contrast to the projection of length, the beam on the mirror The projection width does not change depending on the collision angle.
[0203] Figure 24 shows a schematic representation of the intensity characteristics of a typical beam. Contour 1 represents 90% of the maximum intensity. The percentage lines are labeled, contour 2 is labeled at 80% of the maximum intensity line, and contour 3 is labeled at FWHM (full width at half maximum) strength. The degree line is marked, contour 4 is marked with a 1 / e intensity line, and contour 5 is marked with a 1 / e 2 Mark the intensity lines and outline the contour. 6 is 1 / e 4 Intensity lines are marked. Point 231 is approximately the weighted average point of the beam. Point 232 is at the center of the first contour, and point 233 is at the center of the sixth contour. Yes, and these are all valid points for setting the center of rotation of the mirror. However, Therefore, in order to set the rotation center so as to exceed this point, the height of the gimbal mirror is A large mirror is needed to maintain radiance efficiency.
[0204] Maintaining high radiance efficiency relative to other components is also important. However, The gimbal mirror and first lens that track the laser typically have limitations in terms of radiance efficiency. It is a fixed component.
[0205] Figure 25 shows a schematic side view of a laser diode from a direction perpendicular to the laser's velocity axis. Furthermore, it shows that lens 242 is for operation and is normally used to nearly collide the speed axis. In most cases, lens 242 is a composite lens containing several optical elements. The radiator 241 is connected to the heatsink 243 and radiates the beam 15 onto the interface layer 244. The interface layer 244 has a refractive index n with respect to the wavelength associated with the beam 15. The value of n is , at the air interface at 532 nm it is 1.000293, and in the case of oil or light cement The value increases further. Beam 15 has divergence in at least one direction. Lens 242 The FWHM contour of beam 15 on the front surface is between any two points on the FWHM contour It has a diameter d defined as the maximum distance. Lens 2 is designed to have high radiance efficiency. 42 is at least for the laser 241 emitter
number
[0206] When a lens with a small numerical aperture is used, the beam's radiance is affected by the lens. This can result in reduced system efficiency or a large receiver. These are common situations. This can be disadvantageous. Using a small NA also involves heating the lens holder. This causes two harmful effects. Firstly, thermal expansion causes the lens to become less efficient. Firstly, it involves movement from a fixed position. Secondly, it involves force being applied to the lens, causing distortion in the lens. This reduces its optical quality, and as a result, the beam's radiance is reduced. Furthermore, small numerical apertures (NAs) can also result in reflections directed towards the laser. This can interfere with the laser modes. This can further reduce the initial beam radiance. This also reduces the emission of the emitted beam. This is detrimental to radiance. Light emitted from the edge of the lens is affected by a small NA lens. When used, it may interfere with other parts of the system, such as beam monitors and tracking systems in the system. It may interfere with the operation of the o-bo or other optical elements, or with other parts of the system. This can cause excessive heating, which may interfere with its operation.
[0207] Here, refer to Figure 26, which shows a block diagram of the laser protector 251. As mentioned above, The safety system 31 evaluates the potential for a safety violation, and if such potential exceeds a threshold, The controller 13 is then notified. The controller 13 then instructs the laser driver 12 to beam 1 A gain medium that can become a laser emitting 5 or is used to generate beam 15 is excited Command to stop or reduce the power supplied to laser 252, which may become the generating laser. It is possible. Shutting down the power in this way must be extremely fast. When the power being supplied is suddenly cut off or reduced, a negative charge is generated in the conductor carrying the laser driver current. The pressure can propagate (if it is an electrical conductor) and potentially damage the laser 252. To prevent such damage, the laser protector 251 connects the laser driver 12 and the laser 25 Between 2 and 2, it is typically connected near the laser 252. The laser protector 251 is typical Specifically, diodes, or equivalent circuits / components, such as Zener diodes, Varis A circuit designed to quickly drain such excess negative voltage between current conductors, By continuing this, the laser 252 is protected from negative voltage. As a result, negative voltage is present between the conductors. Even if present, the voltage is safe because the current flows through the protection diode or equivalent circuit. This causes rapid attenuation down to a certain level. The laser protector 251 also protects against overheating or overvoltage. By attenuating the power sent to laser 252 when flow is detected, the laser It can also be used to protect against overheating or electric current waves.
[0208] As will be recognized by those skilled in the art, the present invention is not limited to those illustrated and described above. No. Rather, the scope of the present invention is a combination of the various features described above and sub-components. Both connections, as well as those that can be recalled by a person skilled in the art from reading the above description and that do not exist in the prior art These variations and modifications do not include any other examples.
Claims
1. A system for secure optical wireless power transmission from a laser power transmitter to at least one remotely located power receiving device, The aforementioned power receiving device is configured to convert optical power transmission into electrical power. The aforementioned system, A beam steering device associated with the laser power transmitter, When indicating the presence of a safety hazard, (i) Changing the small signal gain of the laser gain medium in the laser power transmitter, (ii) Changing the scan speed of the beam steering device, (iii) Changing the scan position of the beam steering device, (iv) Record the scan position that defines the position of the power receiving device. A safety system adapted to perform at least one of the following: Includes, The aforementioned safety system Receiving feedback from at least one beam analyzer configured to detect at least one of the optical power level and beam shape of a beam propagating between the laser power transmitter and the power receiver, wherein the detection by the at least one beam analyzer indicates at least one of (i) partial blocking of the beam, (ii) collision of the beam with a transparent object, and (iii) complete blocking of the beam. Receiving feedback from at least one intrusion sensor, the at least one intrusion sensor detecting at least one of (i) a foreign object crossing the beam and (ii) a foreign object approaching the beam. A system adapted to perform this task.
2. The system according to claim 1, wherein the at least one beam analyzer is further configured to detect at least one of (i) the symmetry of the beam, (ii) the polarization of the beam, (iii) the coherence of the beam, (iv) the divergence of the beam, (v) the frequency of the beam, and (vi) the M2 parameter of the beam.
3. The safety system is further adapted to receive feedback from at least one temperature sensor, according to claim 1 or 2.
4. The system according to claim 3, wherein the at least one temperature sensor is adapted to detect at least one of the following: (i) the temperature of the laser power transmitter, (ii) the temperature of the power receiving device, (iii) the temperature of at least one predetermined component of the laser power transmitter, and (iv) the temperature of the surrounding area in which the system is installed.
5. The system according to claim 1, wherein the at least one beam analyzer is further configured to analyze the beam at more than one position along the beam.
6. The safety system is further adapted to receive feedback from at least one sensor, the at least one sensor configured to detect at least one of (i) smoke around the beam, (ii) humidity around the beam, and (iii) current of the laser power transmitter, according to claim 1.
7. The system according to claim 1, wherein the at least one intrusion sensor is further adapted to detect at least one of (i) partial blocking of the beam, (ii) collision of the beam with a transparent object, and (iii) complete blocking of the beam.
8. The system according to claim 1, wherein the laser power transmitter is connected to a laser protector, and the laser protector is configured to protect the laser power transmitter from excessive negative voltage.
9. The system according to claim 1, wherein the safety system is further adapted to assess the potential for safety hazards at at least one pre-scheduled time.
10. The system according to claim 1, wherein the laser power transmitter is configured to receive the recorded scan position which defines the position of the power receiving device.
11. The system according to claim 7, wherein the at least one intrusion sensor includes a controller configured to provide the difference between a signal indicating the optical power level of a beam propagating from the laser power transmitter and a signal generated by the level of the beam reflected from the power receiver and received by the laser power transmitter.
12. The system according to claim 7, wherein the at least one intrusion sensor includes a controller configured to provide the difference between a signal indicating the optical power level of a beam propagating from the laser power transmitter and a signal generated by the optical power level of the beam received by the power receiving device.