Patent Application
20250088280
The present disclosure describes laser technology related to the field of remote information display and interchange within areas having public access, especially as applied to commercial information display in sales areas and shops.
Commercial environments, such as stores and other public buildings may greatly benefit from being able to easily deploy large amounts of electronic information or sales assisting devices in their premises, such as display screens, electronic shelf labels, various sensors, digital cameras and the like. Such systems are able to display digital contents to customers, collect valuable data and provide higher revenues and lower cost of ownership to the property. Display screens may present information, such as information about products, whether relating to price or content, such as nutritional value for example, advertising, warnings, and current information, such as the existence and time limits of discounts on the product, while sensors may sense human presence, temperatures, and electronic signals.
Currently, such deployment on a large scale often has to be performed over a large area and rapidly, and can thus result in poor location of the devices themselves, or in inaccurate documentation of where each device is. For example, should a supermarket employee need to install 1000 display screens on different shelves, by going around the premises and mounting the screens one by one to the shelves, the possibility of human error may make it difficult to know which screen is on a specific shelf.
Location awareness is used on many existing screen, sensor or camera devices, such as smartphones, and such devices are able to transmit their location and may also show dynamic content based on location. Wireless laser tags are another remote information providing system, which provide remote tracking, such as is shown in U.S. Pat. No. 7,229,017 for “Laser Locating and Tracking System for Externally Activated Tags” to E. A. Richley et al, and US Published Patent Application No. 2015/0022321 for “Long-Range Electronic Identification System” to D. K. Lefevre.
There is significant monetary value for operators of such locations in devices such as information screens, sensors, cameras, and similar devices, that enable automatic location and information exchange in public places.
However, many of such current systems are limited in their scope. For instance, lack of functionality can arise when the public place and its devices are located significantly inside a building, where GPS access is limited, or has poor ability to distinguish between nearby items.
The disclosures of each of the publications mentioned in this section and in other sections of the specification, are hereby incorporated by reference, each in its entirety.
The present disclosure attempts to provide novel systems and methods that overcome at least some of the disadvantages of prior art systems and methods, and describes new exemplary systems, which, using a laser beam generated by a transmitter unit in a base station, detect, communicate with and control devices, typically battery-operated, installed in public spaces. The interaction between the laser beam and the device is achieved by equipping the device with a laser detector, selected to emit a fluorescent signal when the laser beam impinges thereon. A fluorescence detector is installed on the base station, and it is capable of detecting the incoherent fluorescence emitted by the device when the laser impinges on the device. A wireless data link can implement the exchange of information and instructions between the base station and the device, that may be needed following positive detection of the fluorescent emission from the device. The system may be advantageously operated using a laser beam in the short wavelength infra-red (SWIR) region, and detection of the beam may be performed by an SWIR laser detector, which may be a photovoltaic cell, a PIN diode, an APD diode, or any other suitable detector, to detect when an SWIR laser impinges thereon. The detector may further be adapted to provide the device with power for its operation and/or for keeping an installed battery charged.
The fluorescent signal is generated by a fluorescent material on or in the device, typically deposited on or near the laser detector, or embedded in the laser detector. Upon impingement of an SWIR laser, the system is adapted to react in at least one of the following two ways:
1. The fluorescent material emits its fluorescence light, which facilitates detection of the device by an external detection device such as an infrared camera, or an infrared detector, or a detector located within the laser emitting base station. The fluorescence signal may also be used to provide a first unique signature, differentiating the device from other objects in its vicinity which may be emitting or reflecting light. The fluorescent light is specific to the fluorescent material used and to the laser used. For example, illuminating Ho:YAG nanocrystals with a 1.9 μm SWIR laser, causes fluorescence at around 2.122 μm, which can be easily detected. This is a very different wavelength from other materials found in a typical environment, which generally do not respond to the 1.9 micrometer laser, or, in the rare case that they do, do not emit 2122 nm fluorescence. The absorption wavelength can typically be tailored to specific laser wavelengths by using semiconductors or semiconductors powder, for example III-V compounds may be tuned from approximately 800 nm all the way to 2200 nm, thus providing a unique fingerprint for the device. Thus the fluorescent material is identifiable by two factors, a unique absorption, tailored to the SWIR laser, and a unique emission, differentiating the devices response from that of the environment.
2. A controller in the base station receives the signal from the SWIR laser detector, and responds by at least one of:
It is possible to identify the specific location of the targeted device by noting the aiming direction of the laser transmitter, and to determine the type and capabilities of the targeted device, according to the responding signals, differentiating it from other illumination in the region, and different nearby devices, for instance, by aiming the laser at a first device, then at a second device, and analyzing and comparing the fluorescent signal and/or the wireless response. This is because only the device at which the SWIR laser is aimed, will respond and emit its characteristic fluorescent signal, and upon detection of the SWIR laser by the SWIR laser detector, the base station controller may instruct the wireless data transmitter to send a wireless identification signal, which uniquely identifies the specific device, thereby providing even more data. The fluorescence response carries very little information, it usually confirms the presence of a device, rather than the device type. It is impractical to use a different laser and detector for each device, so they all use the same laser and the same detector. It is difficult to put a different chromophore on different device screens, though it is possible to provide limited information, such as the type of device detected. Thus, the fluorescence signal simply tells the base station “a device is found here”, while the electronic signal can provide the base station with substantially more identifying and functional information, such as “Device #123456, a type 78 device capable of A, B, C, communication on channel 9, Battery; fully charged, Device ready”.
In a typical system, a filter may be used to filter out sunlight and transmit the laser light, which is absorbed by the SWIR laser detector. Either the filter, the SWIR laser detector or another component in the laser path is configured to emit fluorescence in response to the laser light, facilitating detection of the signature of the device even if it is powered off. In most system it is possible to utilize the detector itself to emit the fluorescent radiation, in such a case it is possible to control the amount of fluorescence by controlling the impedance the detector experiences. When the system is operating, the detector has a lower impedance, and vice versa when not operating. Expressed alternatively, when the system is operating, the photons are using their energy to generate a photovoltaic current, and hence have less redundant energy for generating fluorescence emission. When the device is not fully operational, and no photovoltaic current is generated, the fluorescence level is higher than that when the device is powered off.
If the device is turned “on”, the SWIR laser detector controller is configured to transmit a wireless signal including information about the device such as its ID, properties of the laser detected, such as pulse structure, timing, power, and in most cases, also the device type.
A typical routine that would occur when the system is in use would thus follow at least most of the below sequence, comprising the following occurrences:
The time taken to locate the devices may be important for three purposes. The first is to verify the correct installation of the device. The sooner the confirmation of the installation position and the correct response to the SWIR laser is obtained, the sooner can the installation technician or the store personnel move on to the next installation. The second is for performing an inventory scan, and for locating the devices in a specific area. The third is to verify the line of sight of the base station to all of the specific locations of devices, such as down a complete aisle.
The system can be used for centralized management of the area where the system is installed. Such a management system can show the location of each device and allows for simple control of each device, for example, by sending a data packet to a specific device based on its location.
Such a management system may show a view of the area, typically a store, the view most conveniently being a plan view, with the devices in the store marked according to their location. An operation such as a mouse click, may enable sending content to the device based on its location within the store, and such content may be graphic, or instruction code, or a file, and may be used to display on the screen of the device, content such as advertisements or price reductions. Some of these screens may be incorporated on malfunctioning devices, as identified by their fluorescence and/or retroreflection response, and are known to be malfunctioning either because no data packet response was transmitted to the base station, or a data packet response positively indicating a problem was sent, or any other indication that a problem exists.
In response to the indication of a problem, the store management may send an employee or a robot to fix the problem, for example by replacing the battery or by relocation of a wireless power supply device, or alternatively, it may be possible to correct the problem wirelessly, such as by wirelessly rebooting the device or by wirelessly supplying power to the device, or by updating parameters or software, either remotely or by instructing local maintenance staff. This whole process may be done automatically, even without presenting the store image to a staff member of the store.
This management interface further allows updating settings or content on the devices, for example, automatically, or manually sending a data file to a certain device which causes it to display on its screen, a specific content to customers.
Further applications and details of the setting up and operational methods of specific systems, are provided in the Detailed Description section of this disclosure.
There is thus provided in accordance with an exemplary implementation of the devices described in this disclosure, a system for monitoring at least one electronic device in a region of interest, the system comprising:
In such a system, the electronic device may further comprise a wireless transceiver adapted to enable transmission of data from the laser scanner unit to the electronic device, on notification by the system controller of detection at the laser scanner unit, of fluorescence illumination from the electronic device, wherein the data transmitted to the electronic device comprises at least one of information for display by the electronic device, or instructions for execution by the electronic device.
In any of the above described systems, wireless transceiver is further adapted to enable transmission of data from the electronic device to the laser scanner unit, the data comprising at least one of identity information of the electronic device and an electronic status of the electronic device.
Furthermore, any of the previously mentioned electronic devices may further comprise a battery to enable its operation, and the laser beam is then operative to provide power for charging the battery.
Additionally, the laser scanner unit may further comprise a scanning mirror adapted to scan the region of interest such that the laser beam can locate the position of an electronic device in the region of interest by detection of the fluorescence illumination generated by impingement of the laser beam on the electronic device.
According to yet further implementations of the systems mentioned hereinabove, the laser detector module on the device may comprise an optical filter adapted to reduce the sensitivity of the laser detector module to daylight. Furthermore, the laser beam may have a wavelength within the short wavelength infra-red (SWIR) region.
In yet other implementations of the systems of the present application, the electronic device may be any of an electronic faucet, a remote electronic sensor, an information display screen, an electronically operated window shade, an electronically operated window, an electronic label, and an electronically operated camera system.
There is further provided, according to more implementations of the present disclosure, an electronic device for communicating with a base station, the electronic device comprising:
In such an electronic device, the data package sent to the base station may comprise at least one of identity information of the electronic device, or a state of electronic activity of the electronic device. In either of the previously described electronic devices, the intensity of the fluorescent illumination on impingement of the laser beam may be dependent on the state of electronic activity of the electronic device. In the latter case, the intensity of the fluorescence illumination should be able to provide an indication of a non-functioning electronic device.
Furthermore, the electronic device may further comprise a battery for its operation, and the laser beam may then be operative to provide power for charging the battery.
In such an electronic device, the laser beam from the base station may be configured to scan a region in which the electronic device is situated, such that the laser beam can locate the position of the electronic device in the region by detection of the fluorescence illumination generated by impingement of the laser beam on the laser detector module of the electronic device.
According to yet further implementations of the electronic devices mentioned hereinabove, the laser detector module on the device may comprise an optical filter adapted to reduce the sensitivity of the laser detector module to daylight. Furthermore, the laser beam may have a wavelength within the short wavelength infra-red (SWIR) region.
In yet other implementations of the systems of the present application, the electronic device may be any of an electronic faucet, a remote electronic sensor, an information display screen; an electronically operated window shade, an electronically operated window, an electronic label, and an electronically operated camera system.
In yet another implementation of the systems of the present disclosure, there is provided a system for communication with at least one electronic device in a region of interest, the system comprising:
In such a system, the information from the system controller may further comprise at least one of identity information of the electronic device and an electronic status of the electronic device. Furthermore, the control of at least one function of the electronic device may comprise at least one of instructing the electronic device to display information, or instructing the electronic device to execute a predetermined function.
In any of those described systems, the intensity of the fluorescence illumination may provide an indication of a non-functioning electronic device.
Furthermore, the electronic device may further comprise a battery for its operation, and the laser beam may then be operative to provide power for charging the battery.
In these electronic devices, the laser beam from the base station may be configured to scan a region in which the electronic device is situated, such that the laser beam can locate the position of the electronic device in the region by detection of the fluorescence illumination generated by impingement of the laser beam on the laser detector module of the electronic device.
According to yet further implementations of the electronic devices mentioned hereinabove, the laser detector module on the device may comprise an optical filter adapted to reduce the sensitivity of the laser detector module to daylight. Furthermore, the laser beam may have a wavelength within the short wavelength infra-red (SWIR) region.
In yet other implementations of the systems of the present application, the electronic device may be any of an electronic faucet, a remote electronic sensor, an information display screen; an electronically operated window shade, an electronically operated window, an electronic label, and an electronically operated camera system.
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
Reference is first made to
When the SWIR laser beam 101 impinges on a device 102, and as shown in
Typically, if the device is non-operational, such as by being off, or in a sleep or hibernation mode, a fluorescent signal emitted from the photovoltaic cell has a higher level than from a device that is turned on and operational. The reason for this is that when the photovoltaic cell is not powered, the impingement of photons of the SWIR laser beam on the photovoltaic cell does not generate a photoelectric current, but these photons must give up much of their energy somehow, so it is used to generate fluorescence, and additional heat. The level of the flux is inversely proportional to the impedance of the photoelectric cell, which is highest when it has no applied voltage. This feature of emitting fluorescence even when the device is not operational, enables the base station to detect devices even when they are off or sleeping, with no less reliability than when operating. It also enables the identification of “off devices” easier, this being a useful feature if there is a problem preventing their operation, enabling the solving of the problem, for example by supplying power to them, or by turning them on. Once operational, the device can transmit a wireless data packet indicating its identity ID and its “ready” status. In an environment such as a store, where multiple devices are operating and some may not be operating, identifying the status of each device is critical for business performance. The presence of many such devices in the same space may create a problem in identifying the location and status of each device quickly and efficiently, and of providing relevant content to the devices.
Location functionality, using the SWIR laser, may also be achieved by adding a retro-reflector to the device, or a filtered retro reflector which will reflect only the SWIR laser wavelength. This retroreflected beam is detected by a detector in the base station. The advantage of a retro reflector over that of detecting fluorescence emission, is that it is quicker to respond, and may be smaller and of lower cost, and can provide a signal of intensity tens of dB greater than the fluorescence signal, but its level cannot be controlled. Consequently, it is impossible to distinguish between a device that is not operational, and a device that is operational, but for instance, whose data transmission is somehow blocked. Blocking of the data transmission may occur for instance, as a result of the IR electronic channeling diode being covered by a price tag, or, by inadvertent location of a device behind another object on the shelf. If the feature for determining the operational status of the devices is not necessary, it may be possible to use a retroreflector instead of a fluorescent signal. It is also possible to use a retro reflector in addition to a fluorescent signal to allow detection of the devices by redundant methods.
Reference is now made to
The potential problematic devices 302 may be detected by noting any of:
Reference is now made to
Most of the fluorescence signal, whether at a full level or attenuated, is typically emitted in a solid angle of at least 0.85 steradian, and typically can be detected from approximately 4.5 steradians, albeit at such large angles it may be difficult to differentiate attenuated from non-attenuated signals. The signals can also typically be detected at distances of up to 30 m, as long as there is a line of sight from the device to the base station. Generally, this is ensured by impingement of the SWIR laser beam along essentially the same path. Hence the SWIR laser beam and the fluorescent signal may be used to identify which devices are visible from specific points, such as from the customer's position of view, or from a camera, such as a security camera or an inventory tracking camera, or from a robot's position of view, or from a charging device's position of view.
Reference is now made to
Reference is now made to
A number of features and methods of setting up and operating the system are now outlined, to present additional novel uses and methods of use of the systems of the present disclosure.
During installation, the device may be configured to be in “installation mode”. During this procedure, the SWIR laser scans the area rapidly, in an effort to reach the device sought as quickly as possible. The SWIR laser scanner may be caused to scan the room as a result of an instruction issued by the device. In installation mode, upon detection of the impingement of the SWIR laser, the device informs the system that it is installed and operational so that the system may register it and its location. It also typically informs the installer that its setup is successful, for example by showing an OK signal on the screen.
While the devices described hereinabove, have generally been described as intended to provide information, and therefore are equipped with a screen, the system can also be used for devices for other purposes, without a screen. One common application is for the control of cameras, and especially security cameras (used as the non-limiting example in this description), traffic cameras, or crowd control cameras. The same advantages as have been described hereinabove in the store scenario, namely rapid discovery, quick positive feedback on correct installation, reporting of the line of sight, centralized management, and the ability to remotely detect a faulty device or a device not activated, can also be advantageously used in such a camera system. Though the security camera device does not need a screen, it may need a pan/tilt stage for aiming in a desired direction, and/or zooming instructions for closing in on an area of interest. Therefore, in the context of the currently described system, upon detecting the impingement of the SWIR laser, the camera module would emit a fluorescent signal, typically indicating the state of the controller in the camera module, and then send out a wireless data packet, assuming that the controller is operational. In response the management system or central surveillance facility would record the position of the camera, and would enable the sending of instructions to it, which could include any or several of pan, tilt, zoom, download, and firmware update functions, or any other instruction required to utilize the facilities of the security camera device.
Electrically Operated Faucets Another device which may benefit from the currently described systems is an electric faucet, activated by the user's hand motion in the field of view of the hand detector. While the problem of locating the position of faucets or other water valves is generally unimportant relative to the problem of locating portable screens or cameras, the abilities described in this application, including the detection of whether the faucet controller is turned on or off, is very advantageous, since a faulty electric valve may be a critical problem, needing rapid detection and repair. Thus, for example, battery replacement or replacement of a damaged part can be detected and repaired rapidly.
Another type of device which may benefit from the systems of the present disclosure are remote sensors. While sensors, like the camera systems mentioned above, may not require a screen, even though there are sensors which do include a screen for showing the measured value, such as temperature sensors, the locating of sensors in a large industrial installation, for instance, and determining their operational status, would be a very advantageous undertaking, especially for maintenance operations on such an industrial installation. In the case of such sensors, the SWIR laser detects the location of the sensors, and the system determines their operational state based on measurement of the fluorescence generated in the device and on the consequent digital response, and may then send content wirelessly to the sensors in order to ensure accurate measurement. Such content could include calibration updates, a measurement schedule, firmware updates, or other necessary inputs which can be sent wirelessly to the sensor.
Yet another type of device which may benefit from use of the current system and its control of remote devices are electrically operated shades. While typically, such shades do not come equipped with a screen, the current electric shade device, if equipped with a screen, may also serve to show temperature, time, weather, illumination details and other valuable data relating to the functionality of the shade. In a commercial setting, such shades may be powered by a battery, or be equipped with a backup battery, or powered by a wireless power system. In such a setting, it is difficult to know from afar if a shade is operational or not, and accessing it physically is time consuming, since it generally requires bringing a step ladder to access the shade operation mechanism. The ability of the current devices to enable identification of the operational state of the shade from afar, using the SWIR laser system of the present disclosure, is very useful. Following the identification of the device using the SWIR laser, and the data response, if returned, the system may then send commands to the electric shade, and to perform such actions as updating its software, charging its battery, or ordering a replacement battery.
Another type of devices which may benefit from use of the current system and its control of remote devices, are electrically operated windows, meaning windows which electronically change their optical properties. Some of such window operational devices may also be equipped with the screen of the current devices, such as to show temperature, time, weather, illumination details and other valuable data. In a commercial setting, such windows may be powered by a battery, a backup battery, or from a wireless power system. In such a setting, it is difficult to know if a window is operational or not from afar, and accessing it physically is time consuming, since it generally requires bringing a step ladder and a screwdriver to access and repair it. The ability of the current device to enable identification of the state of the product from afar using the SWIR laser is very advantageous. Following the identification of the device using the SWIR laser, and the data response if should return, the system may then send commands to the electric window, and to update its software, charge its on-board battery, or order a battery replacement, or any similar maintenance or repair activity.
There are a number of aspects of the systems of the present disclosure which enable the implementation of electronic shelf labels. Thus for instance, the screen attached to the systems described hereinabove may also serve as a smart electronic shelf label, is content can be changed remotely according to the requirements of the store management. In a similar manner, the camera or sensors attached to the currently described systems, may also serve as the major components of a smart shelving system.
Another feature of the systems of the present disclosure is the ability to aid an installer in the correct installation of the device itself. Installing the device in a situation where there is no line of sight from the device to the SWIR laser emitter, may cause a number of problems, ranging from the blocking of RF signals by metallic objects in the line of sight, to the simple inability to view or update the device status on the facility's central control screen. For that reason, the device may include an output ability, capable of informing the installer if the SWIR laser is aimed at the SWIR laser detector, or not. Such an output ability may be a notification on the device screen, an indicating LED, a sound emitting system or a wireless notification to the installer. The device may also include an input mechanism, such as a press button, or a special mode which may be initiated locally or from a wireless network. The input mechanism may cause the device to behave differently from its normal operation for a short time, for example by sounding a unique “beep”, turning on/off a LED diode in a specific pattern, or displaying an installation message on a screen. Typically, the device may switch back to the normal operation mode after a predefined time, ranging for instance from 1 minute to 24 hours, or as soon as the SWIR laser has been detected. This may help an installer to locate a position where the device is within the line of sight from the SWIR laser scanner.
As soon as the impingement of the SWIR laser scanner has been detected, the device may enter a setup mode, which may allow the selection of various settings, such as screen brightness, location aware position, sending an affirmative signal to indicate installation condition, or scanning a barcode relating to the position.
Reference is now made to the SWIR laser scanner system 100, shown in
As previously mentioned, the fluorescence signal detector typically includes a filter for filtering out direct sunlight, while transmitting the fluorescence signal. In some applications, specifically indoor applications, the sunlight blocking filter may be omitted. The sunlight blocking feature may also be replaced by a cover layer on top of the diode, or by selecting a diode which has low response to wavelengths in the visible spectrum, which effectively serves the same purpose as the sunlight blocking filter. At the other end of the communication channel, in the base station, the detector used to detect the fluorescence is typically equipped with a laser blocking filter. The laser blocking feature is very important but may be achieved either by a filter or by physical separation of the laser and scanner system from the fluorescent signal detector or by a filter, preventing the SWIR laser itself from reaching the detector.
An advantage of the filter based system is that the diode may “view” the world through the scanning mirror, and thus have only a narrow field of view, and it can thus be exposed to much less signal compared to a diode which views a very wide field of view. An advantage of the wide field of view system is that it is optically simpler and may operate even without a filter. The fluorescence signal detector may also include a diode for detecting the signal, and typically also an amplifier and an analog-to-the digital converter.
Referring back now to the central management console of the store implementation, the present system allows control of the devices installed in the store. Typically, it provides access to at least some of the following features:
1. Listing of all the devices.
2. Position and status of each device, including the battery status, the content playing, the location, the detectability by the SWIR laser, as measured on a nominal scale ranging from YES to NO, a daily/weekly/monthly/annual summary of the detectability check, the number of people counted by a camera or sensor on the device, the number of operations performed using the device, and the status and history of the sensors of the device.
3. Statistical summaries of the status of the complete system, such as the number of devices, the number of operational devices, statistical summaries of sensor measurements over different time periods, such as by the hour, day, week, month, shift, or any other period, the number of devices detected by the SWIR system, a map of the locations from where the devices are visible.
4. The ability to perform the operations on a specific device, such as to update content, to turn off, turn on, change settings, update firmware of a device.
5. The ability to select a set of devices based on criteria, such as all the devices in a region of the area, or all the devices which belong to a specific group, or all the devices which are next to dairy products, and similar criteria.
6. The ability to perform the same operation, such as to update content, on all of these devices automatically.
7. The ability to control the operational parameters of a group of devices, such as, for example, an instruction to “update the content on all the screens on aisle 4”.
Referring now to the characteristics of the fluorescent material, it may be a chromophore, a chromophore embedded in a plastic or glass matrix, or a chromophore embedded in a semiconductor matrix, such as a “quantum dot” type semiconductor with the quantum dots tuned to the SWIR laser wavelength.
The fluorescent material is tuned to absorb the SWIR laser, which means that it has a bandgap less than 1.25 eV and typically greater than 0.5 eV, these bandgap levels matching the SWIR region shown in
The fluorescent material typically absorbs the SWIR laser, and emits fluorescent light, also in the SWIR region, but typically at a longer wavelength. Typically, the emitted light is at least 50 nm longer than the laser, which enables separation of the two signals using filter(s).
A conveniently available SWIR laser source used in some of the systems of the present application, emits at 1310 nm. and generates fluorescence at 1430 to 1450 nm.
If the host material is a plastic or glass, it is generally transparent to the SWIR laser (typically PMMA, PC, Polystyrene, or various glasses would be used). If the host material is a semiconductor, it would typically have a higher bandgap than the fluorescent chromophores, suitable materials being Si, GaAs, Ge, InP and combinations of III-V or II-VI semiconductors.
An alternative to the “quantum dot” approach is a semiconductor material in which a thin layer of fluorescent semiconductor is grown on top of the other layers. A suitable substrate on which to grow the fluorescent material would be the SWIR laser detector.
In some cases, some of the layers in an SWIR laser detector may already be suitable for emitting fluorescent light, and the layer on top of such may be transparent enough to allow some of that fluorescent signal to escape the SWIR laser detector. It is particularly advantageous to use such an SWIR laser detector.
The installation is typically performed in two separate steps; firstly, the installation of the SWIR laser scanner, usually in the base station, and typically mounted on the ceiling or in a location where it has an extensive field of view of the region where the devices are to be installed, and secondly, installation of the devices themselves. There is a need to readily verify that the devices and the SWIR laser scanner are positioned well and in good working conditions, as well as to configure them for their purpose, usually based on the location in which they were placed. As an example, by setting device at a first location to perform a specific task (such as displaying a first ad), while configuring another device at a second location to perform another task (such as displaying a second ad, or a price, or nutritional information for a product). Installation can be done in any order, SWIR laser scanner first, devices first, or some of the devices may be installed before the SWIR laser scanner, while others after it. However typically the SWIR laser scanner is installed before the devices are.
The SWIR laser scanner consists of an SWIR laser emitter 103, emitting an SWIR laser beam 101. A scanning mirror 104 is positioned such that it can direct the laser beam in different directions. The SWIR laser scanner also comprises at least one sensor 106 or 107 for sensing signals returned from the devices, whether the fluorescent signal, a retroreflected signal or the wireless data transmission, a base station controller 108 to control all the above components and to receive and process signals from the sensors, and a data modem (not shown in
However, communication with the devices may be done from a different system and not from the SWIR laser scanner.
The SWIR laser scanner may also be equipped with an indicator, for indication of the installation status of the device. Such an indicator may be at least one of:
The SWIR laser scanner installation comprises attaching the device to its selected position such as specific point on the ceiling, connecting it to the power supply, and ensuring that the SWIR laser scanner is operating in a “quick approval mode”, to be further explained below. An “installation verifying device”, also further explained below, is used to verify to where lines of sight to the SWIR laser scanner exist and to where they are absent. At the end of the installation the SWIR laser scanner is switched to “normal operation mode”.
The SWIR laser scanner scans the room, typically at a fast scan pace. When the SWIR laser scanner detects a device, it may halt its scan for a short time period to allow the device to detect the SWIR laser with high probability and to respond to the SWIR laser. Once that is performed, the laser beam scan can move on at its high scan rate to other devices, to verify which devices are within the SWIR laser scanner's field of view, and to determine the extent of the SWIR laser scanner's field of view. The SWIR laser scanner may also be equipped with a visible laser, essentially aligned with the SWIR laser, to provide a visual representation of the field of view to the installer. Should the installer detect a problem in the field of view coverage of the SWIR laser scanner relative to all of the devices which it intended to be in communication with, the SWIR laser scanner may be repositioned, or the surroundings may be changes, such as, for example, by moving a blocking object.
In the normal operation mode, the SWIR laser scanner scans the area, looking for fluorescence signals from devices. When the SWIR laser scanner detects a device, it records the direction in which the device was found, awaits a wireless signal sent from the device indicating its status, and updates the status in the system memory. According to a specific implementation of the system and method, the SWIR laser scanner may direct the SWIR laser to the device for an extended time, in order to charge its internal battery, to allow for long-term continued operation of the device.
The installation verifying device is a distinctive device, carried by the installer, and equipped with an output device adapted to indicate the impingement of the SWIR laser, enabling the installer to detect the region of the field of view of the SWIR laser scanner, and also the correct functional operation of the SWIR laser scanner.
The device installer may position a device in a specific position, and switch the device to the “installation verification mode”, as explained below. If the SWIR laser scanner is not in “quick approval mode”, the installer switches the SWIR laser scanner to “quick approval mode”. If the device does not indicate it has line of sight to the SWIR laser scanner, the installer should alter its location.
In the installation verification mode the device is configured to indicate to the installer that it has detected the SWIR laser, such as by showing a message on the screen, by a visual or auditory confirmation, or by sending a confirmatory wireless signal to the SWIR laser scanner, or to the SWIR laser scanner control system, or to another system such as the Smartphone of the installer.
At the end of a successful installation verification mode, the device may enter a configuration mode allowing it to be configured either by the installer or remotely.
Besides the above mentioned search functionality of the SWIR laser scanner, the presently described SWIR laser scanner include a number of electrical features of the SWIR laser scanner which increase safety in the use of the system.
There are two distinct, safety related, functionalities which the control system of such SWIR laser scanner has to perform, whether executed by a single controller, or by separate controllers for different aspects of the total safety related total control needs. These two functionalities have different objectives and operation, even though they may be implemented from the same controller or controllers.
The first functionality is related to the overall safety of a technically operational system, and its objective is to ensure that the system does not cause harm. That function is accomplished by estimating the probability of dangerous exposure of a person to the laser beam, and comparing the likelihood of such exposure to both internal and external standards. If the criteria programmed into the controller are such that the operational situation indicates the likelihood of dangerous exposure, the controller is instructed to turn the laser off, lower its power or direct it elsewhere. The controller generally has a number of different methods to perform these actions in a technically functional system, including such actions as reducing or stopping the power to the laser driver, directing the laser to a safe place, disconnecting the anode or cathode power leads, and others. Such methods are part of the normal safety procedures implemented by such a laser system, and as described in a number of patent applications owned by the present applicant.
The second functionality is directed at system diagnostics, aimed at detecting malfunctions in the system, and responding to them safely. In this implementation, a parameter such as generated or reflected SWIR laser power is measured, and may be compared to another parameter, for instance the laser current and/or its temperature, the comparison or the original measured parameter or a function of it, being tested against some predetermined limits, and a response of the controller generated if the situation deems that necessary. Such safety functionality is described in International Patent Application Publication No. WO 2018/211,506 for “Flexible Management System for Optical Wireless Power Supply” and No. WO/2019/064305 for “Fail-Safe Optical Wireless Power Supply”, both co-owned by the present applicant. Additionally, the controller should also be diagnostically safeguarded, typically, by both internal and external watchdogs to ensure correct functionality, such that it is configured to terminate the laser, if the controller is showing any apparent malfunction. In some implementation, a single watchdog or other means of ensuring proper operation may be used.
One particular fault that may arise is related to the temperature protection of the system, and particularly of the laser. As the system warms up, a situation can be reached where the temperature of the laser emitter becomes excessive, and the thermal safety switch shuts down the entire system, rendering the location being served by the system as unprotected. According to a further aspect of the system diagnostic routines of the SWIR laser scanner, the thermal safety criteria are relaxed somewhat, such that a complete system shutdown is not activated by a local thermal overheating in the laser, but rather, the power of the emitted laser beam is reduced to some lower level, while all of the system functions continue to run, such that the system can recover from a thermal overload without losing its entire operational capabilities.
There remains, however, one mishap which is not readily safeguarded by such protective control features, and that is the situation in which a physical short circuit, or even an indirect short circuit such as could be caused by a failed component allowing current passage even when not enabled by the control function, allows current flow though the laser diode source, even when none is allowed by the controller or controllers. Such a short circuit enable the system to operate in a mode that would project a beam of high power in an unsafe manner. In any such situation, the normal safety precautions may not be operative, as such a short circuit may lead to a drop in system voltage below some component or sub-system operating voltage, or the high temperature resulting from the malfunction may cause some components to fail, or other consequences of the short circuit may lead to a controller failure, any of such situations possibly enabling passage of a current which may empower laser emission when none should have been permitted by the supposedly electronically sound control system.
The presently described system incorporates a number of features which ensure that in such a possibility, the system is provided with protection that will prevent unintended laser emission under such circumstances in which physical or electronically virtual short circuits enables an operating current to pass through the laser diode. Such features include both physical insulation of the laser leads, enabling continued operation of a controller using current storage features, and independently controlled switches in the anode and cathode leads of the laser that are activated by a novel power supply voltage arrangement, thereby providing protections hitherto unavailable in conventional laser transmission systems.
Reference is now made to
In the system of
Although such gated switches have been used in previous systems, to provide an additional channel for interrupting the laser diode current, as indicated by the control lines to the switch gates from the main controller I, the novel use of such switches in the presently described system arises from the manner in which the switches are powered, relative to the other electronic modules and functions of the system. The operation of these two gated switches makes use of the fact that most infra-red laser diodes typically operate at low voltages, in the region of below 1.5V. This is a significantly lower voltage than that used by most other electronic components associated with the electronic circuitry of the system, being generally based on Si semiconductor technology, which cannot operate at such a low voltage. which have a higher operating voltage, typically 1.7V, 3.3V, 5V or 12V or others.
In order to implement this scheme, both the anode switch and the cathode switch can be controlled by an additional controller function, called in
At least one of the two switch gates is arranged to be in the normally non-conducting state, and the laser current is enabled during normal operation by holding the gate in its conducting state by a voltage supplied by controller II. When that latching voltage drops, the gate will revert to the open non-conducting state. The switch gates, or more specifically, the gate controller circuits, are driven from the system main power supply by a separate operating voltage, higher than the voltage supplied to the system controller or the laser driver, or any other electronic function in the system. In the event that a physical short circuit occurs, resulting in the application of a voltage more than 1.5V onto the anode lead of the laser diode, the laser diode will turn on and emit a laser beam, even in a situation when the laser driver is in its off-state and the anode switch is non-conducting. The same situation applies if such a circuit malfunction occurs in the laser driver, and a current is delivered to the laser even when not instructed to be in an ON condition. Since the laser diodes operate at 1.5 v or less, and inadvertent application of another voltage present in the circuitry will be higher than 1.5 v, the increased current drawn from the main power supply may cause a fall in the main power supply voltage to all of the control functions of the system, or alternatively, a fall to a level which is not high enough to reliably operate the controller or its watchdog. Since the gates of the switches are actuated at a higher voltage than either the controller or its watchdog, or both, the fall in voltage will switch the gated switches to their non-conducting state independently of the situation of the controller or its watchdog. Bringing either of those switches to the non-conducting state will thus stop the diode laser current, and bring the system to a safe state, regardless of the functional action of any of the other circuit controllers or electronic safeguard mechanisms of the system.
As an alternative and second method of protecting the system from such a short circuit fault, the main controller may be powered from its power supply with a parallel energy storage device, such as a capacitor, a battery or a coil, thus enabling it to operate for a time long enough to cause the laser to turn off when such a fault is detected, even when power to the controller is turned off. The watchdog may also reset the main controller correctly if it stops operating correctly. Typically, such a reset function is also configured to cause the laser to be turned off until the controller has resumed normal operation. At least one of the switches, anode or cathode, is normally non-conducting, such that if the controller is not powered on, the laser, under normal conditions, cannot be powered on.
In a second alternative situation, if the main controller voltage drop is sufficient to cause the main controller to malfunction, and therefore not to respond by reducing the unexpected and uncontrolled laser diode current, the feature of making the switch operation dependent on a higher operating voltage than the system controller or the laser driver, means that the switches will open, and hence terminate the laser diode current regardless of what the system controller or the laser driver are attempting to do.
Thirdly, a main power switch may be provided, enabling the controller to control the power supply to all the parts mechanically accessible to any point in the circuit electrically connected to the laser anode or cathode. This protection is especially important when a C-mount laser diode is used, since such a C-mount has large areas of exposed metallic surfaces being part of the diode conductors, which could readily be short circuited to ground or to another live metallic contact within the laser generator enclosure, in the event of a mechanical intrusion, or a mechanical fault, such as a loose wire connection becoming free.
Fourthly, all the points in the circuit, including the laser sub-mount, should be electrically insulated. This may be a difficult task to achieve completely without having an effect on the cooling requirements of the laser diode. Consequently, it is advisable that this safety feature be relied upon only in conjunction with at least one of the other features described hereinabove.
Finally, a laser power metering system may be added to the system for comparing the measured laser output power of the laser diode to the expected laser output power according to the settings of the laser diode controller, or, in the event of the use of more than one control system of any of the above described safety arrangements, according to the settings of the controllers. The expected output power should depend on the operational state of the system, namely whether in scan/search mode, or charge mode. Should this metering system find a significantly higher measured power than is programmed by the controller settings, this indicates a system error or a system mishap, and the lasing should be terminated by use of one or more of the switches mentioned above. The power meter may be a separate controller or the central controller or even a component in, for example, the laser driver.
The beam emitted from a laser diode typically expands comparatively rapidly with distance, as compared with other types of lasers. Consequently, a collimation system is needed to generate a more collimated beam needed for efficient charging.
The collimation system is typically also controlled by a controller, advantageously the same controller as used to control the current to the laser diode. The collimation system may operate by adjusting the axial position of a collimating lens or lens system, thereby controlling the beam expansion, the Rayleigh length and beam width. The axial position may be any form of linear actuator, such as magnetic, thermal, piezo-electric, or electro-mechanical, and the actuator may be controlled by means of another switch whose control input may be made through the switch gate. Alternatively, the collimation may be changed by modifying the laser parameters, such as the laser chip position, the laser wavelength, the beam divergence or another characteristic, by changing an electrical input signal to the laser diode.
When switching to scan mode, the controller(s) allows current to flow through both laser diode switches, and also adjusts the current flow through the lens position actuator, or through another system element to control the beam divergence as mentioned above, to bring the collimation of the laser to “wide mode”, in which the beam expands towards the end of the system's intended operation range. When switching off, the controller typically blocks the current through at least one of the laser diode switches.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. Furthermore, it is appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of various features described hereinabove as well as variations and modifications thereto which would occur to a person of skill in the art upon reading the above description and which are not in the prior art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 289682 | Jan 2022 | IL | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IL2023/050023 | 1/7/2023 | WO |
