A method and a system for detecting if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package while it is closed

Abstract

This invention relates to a method and a system for operating a light detection system configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed. After closing the package incoming light intensity is detected and utilized to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window. If the light intensity is detected to be within the first light intensity window, the light detection system remains in the first low energy mode. If, at later time point, the detected light intensity is above the first upper-threshold light intensity level the light detection system is set to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered. At the higher energy mode it is determined if the lid has been opened or not. If not, the detected light intensity is utilized to dynamically updating the first reference light intensity window to a second reference light intensity window

Description

[0001] A METHOD AND A SYSTEM FOR DETECTING IF A LIGHT EVENT DETECTED IN A CLOSED PACKAGE HAVING A LID AND CONTAINING AN ASSET IS CAUSED BY OPENING THE LID OF THE PACKAGE OR BY AMBIENT LIGHT ENTERING THE PACKAGE WHILE IT IS CLOSED

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a method and a system for detecting if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed.

[0004] BACKGROUND OF THE INVENTION

[0005] With the expansion and growth of global sourcing in the supply chain, more prevalent interest has been placed on the automatic and electronic position tracking of sensitive assets such as pharmaceutical products throughout the supply chain from a production site to a destination site.

[0006] Electronic devices such as trackers or logger devices are used to track the position and / or the environmental related parameters such as the temperature of such sensitive assets in real time throughout the supply chain by sharing the location together with one or more environmental parameters such as the temperature on a regular basis, e.g. every one hour.

[0007] When the packages reach the destination site there are several different events that may be utilized to confirm that. One event may as an example be a light event that is triggered when the package is opened by a sensing device arranged within the package. Another solution may include using two different events such as a geofence event where the electronic device associated with the package triggers a signal when it is within a given radius around the destination site and the light event that is triggered when the package is opened.

[0008] Figure 1 depicts graphically a package 100 containing an asset 106 such as a pharmaceutical product and a tracker or a logger device 101, comprising a light sensor 102, a transmitter 103 and a processor 104, where the light sensor 102 is configured to detect a light event when the lid 109 of the package is opened. The processor is configured to, amongst others, instruct the transmitter 103 to transmit the signal event to an external control computer 105 when the lid 109 of the package is opened. A disadvantage with the solution depicted in figure 1 is the unnecessary wake-ups (false-positive) of the processor, e.g. the Microcontroller Unit (MCU), which occur e.g. because the lid is not properly closed or because of cracks / openings in the package permitting a portion 110 of ambient light 108 to enter the interior of the package. Such unnecessary wakeups can trigger an event stating that the shipment and asset has reached the destination location and that the shipment has been opened, although this may not be the case.

[0009] SUMMARY OF THE INVENTION

[0010] It is an object of the invention to reduce and preferably eliminate the above-mentioned unnecessary wakeups of the processor (MCU).

[0011] In general, the invention preferably seeks to mitigate, alleviate or eliminate one or more of the above-mentioned disadvantages of the prior art singly or in any combination. In particular, it may be seen as an object of embodiments of the present invention to provide a light event detection device and a method that solves the above-mentioned problems, or other problems.

[0012] To better address one or more of these concerns, in a first aspect of the invention a method is provided for operating a light detection system comprising a light detector, a light source and a processor for controlling the light detector and the light source, where the light detection system is configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed, where the method comprises:

[0013] • detecting, by the light detector, subsequent to closing the package, incoming light intensity in the closed package,

[0014] • utilizing, by the processor, the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window,

[0015] • setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window, wherein the method further comprises:

[0016] • setting, by the processor, the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered, where at the higher energy mode it is determined if the lid has been opened or not by means of: o emitting, by the light source, a light to an inner side on the lid of the package, o detecting, by the light detector, reflected light from the lid, o comparing the detected light intensity with a pre-defined reference indicator, where in case the comparing results in that the lid has not been opened,

[0017] • setting the light detection system to a second low energy mode,

[0018] • utilizing the subsequent detected light intensity in determining a second upper-threshold light intensity level and a second lower-threshold light intensity level, and

[0019] • utilizing the second upper-threshold light intensity level and the second lower-threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window.

[0020] Accordingly, by dynamically changing the reference light intensity window in this way the likelihood of unnecessary wakeups is minimized because the second reference light intensity window is adapted to the new ambient light intensity. This could as an example be where the closed package is moved from an area where the light intensity is low, such as a room with no window, to an area where the light intensity is high.

[0021] In an embodiment, the first low energy mode is a mode where the processor is in sleep-mode. In another alternative embodiment, the second low energy mode is the same as the first low energy mode, i.e. where the processor goes back into sleep-mode.

[0022] In a preferred embodiment, the method further comprises, in case the comparing results in that the lid has not been opened, switching the light source off. Accordingly, the light source is only activated where it is determined that the package has been opened.

[0023] In a preferred embodiment, the emitted light is emitted with a pre-defined frequency, where the pre-defined reference indicator includes light intensity threshold, and where the step of determining if the package has been opened includes,

[0024] • comparing the light intensity difference between detected reflected light from the lid and in the absence of reflected light where the light source is turned off, where if the light intensity difference is below the light intensity threshold the package is determined to be opened via the lid. The fact that the light intensity difference is below the light intensity threshold when the package is opened via the lid is because the light difference when the light source is emitting light and in the absence of emitting light is significantly less because the light sensor is fully exposed to the ambience light when the light source is turned off, whereas if the package is closed the light intensity is much less in the absence of emitted light. When the package is opened, a reflection from one or more remaining walls or partly from the lid although being open will cause a partial reflection that will be detected by the light detector. Therefore, comparing the pattern of light intensity difference when the lid is closed is significantly larger than when the package is open due to the exposure of the ambience light.

[0025] Accordingly, a reliable solution is provided where the reflected light is utilized as an indicator in determining if the lid has been opened or not, where an additional safety measure is provided to prevent that a minor ambient light entering the package generates the falsepositive event stating that the package has been opened when it has not been opened. The light source may include any type of light emitting diode (LED) or any other type of small and compact light sources.

[0026] In an embodiment, the method further comprises triggering a signal event or inventory related event if the package is determined to be opened via the lid and transmit the signal event to an external control computer. The external control computer may be any kind of a platform system where this data is received and subsequent steps are taken, including stating that the shipment has reached the end-location and where the shipment may be closed. The inventory related event may be used to update the manufacturer's inventory status of the asset, which may be a pharmaceutical product.

[0027] In an embodiment, the step of utilizing the detected light intensity to determine a first / second upper-threshold light intensity level and a first / second lower-threshold light intensity level comprises defining multiplication constants or variables a and P, where 0< a<l and P>1, where the first / second upper-threshold light intensity level is when P is multiplied with the detected light intensity, and where the first / second lower-threshold light intensity level is when a is multiplied with the detected light intensity. The selection of these constants or variables a and P may also depend on the detected light intensity.

[0028] In an embodiment, the asset is selected from: pharmaceutical product, food or beverages, or any type of sensitive products such as electronics, sensitive materials etc.. In an embodiment, the light source, light detector and the processor are an integral part of a tracking or logger device configured to track the position of the asset, optionally together with one or more environment related parameters such as temperature, in real time during transport from an origin location to a destination location.

[0029] In an embodiment, the second upper-threshold light intensity level and the second lower- threshold light intensity level and thus the second reference light intensity window is different from the first upper-threshold light intensity level and the first lower-threshold light intensity level and thus is different from the first reference light intensity window. This is preferred when e.g. there is a large difference in the ambient light intensity, e.g. a package is moved from a room with low intensity next to a window where the light intensity is very high or vice versa. In such a situation it is necessary to dynamically update the first reference light intensity window to the second reference light intensity window.

[0030] In a second aspect of the invention, a light detection system is provided configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed, comprising:

[0031] • a light detector for detecting, subsequent to closing the package, incoming light intensity in the closed package,

[0032] • a light source,

[0033] • a processor configured to: o utilizing the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window, o setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window, o setting the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered, where during the higher energy mode the light source emits light to an inner side on the lid of the package and the light detector detects reflected light from the lid, where the processor is further configured to: o comparing the detected light intensity with a pre-defined reference indicator where in case the potential box opening event indicates that the lid has not been opened, o setting the light detection system to a second low energy mode, o utilizing the subsequent detected light intensity in determining a second upperthreshold light intensity level and a second lower-threshold light intensity level, and o utilizing the second upper-threshold light intensity level and the second lower- threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window.

[0034] Thus, a system is provided that minimizes or eliminates false positive alarms. This thus enables moving a closed package from one area with a first ambient light intensity to another area with second higher ambient light intensity, where with the dynamical update of the light intensity window, the possibility of false-positive alarm is reduced or eliminated. This would also cover scenarios where the difference in light intensity is significant.

[0035] The low energy mode may in an embodiment be understood as the energy mode where the processor is in sleep-mode. The light detector is configured to activate the processor to be in activation-mode when the detected light intensity is detected to be above the first upperthreshold light intensity level.

[0036] In an embodiment, the light source, the light detector and the processor are comprised in an electronic device. Moreover, the electronic device may further comprise an energy source, a memory, a communication module, where the processor further operates the energy source, the memory and the communication module. This electronic device may also be understood as a real time tracking device or a logger device, that monitors at least one environmental parameter of the asset together with the position of the asset in real time.

[0037] During use, the electronic device is placed within the closed package, where the light source emits light towards an inner side of the lid and where the light detector is placed relative to the light source such that the light detector is at least partially facing the lid and detects reflected light from the lid, where the detected reflected light is processed by the processor and compared with a pre-defined reference indicator when determining if the lid has been opened.

[0038] Accordingly, by utilizing the reflected light as an indicator in determining if the lid has been opened or not, it may be prevented that a minor ambient light entering the package generates the false-positive event stating that the package has been opened when it has not been opened. The light source may include any type of light emitting diode (LED) or any other type of small and compact light sources.

[0039] In an embodiment, the processor is configured to instruct the light source to emit light with a pre-defined frequency, where the pre-defined reference indicator includes light intensity threshold, and where the step of determining if the package has been opened is based on comparing the light intensity difference between detected reflected light from the lid and in the absence of reflected light, where if the light intensity difference is below the light intensity threshold the package is determined to be opened via the lid.

[0040] It should be noted that the term detecting reflected light from the lid may also understood as detecting the reflected light from the one or more remaining sides within the package, but the reflected light from the lid is by far the dominant reflection factor.

[0041] The light intensity threshold may in an embodiment be adjustable, which may be fully automatic when setting up the threshold for the electronic device. Accordingly, by utilizing the light intensity difference as the reference indicator, a minor ambient light entering the package will not cause a false-positive event.

[0042] In an embodiment, the processor is configured to instruct the light source to emit light with a pre-defined frequency pattern and where the pre-defined reference indicator includes light intensity having the pre-defined frequency pattern, and where the step of determining if the package has been opened is based on comparing detected frequency pattern of the detected reflected light with the pre-defined frequency pattern, where in case of non-match the package is determined to be opened via the lid. Thus, by utilizing the frequency pattern of multiple reflected light events as a reference indicator, less reliance is made on the light intensity but instead on the detected frequency pattern. A highly reliable solution is thus provided to determine whether the package has been opened or not.

[0043] In an embodiment, the processor is configured to trigger a signal event if the package is determined to be opened via the lid, and instruct a transmitter comprised in the electronic device to transmit the signal event to an external control computer. The external computer, which may be a part of an internet platform, may thus e.g. automatically close the shipment without any manual labor. Also, in case the package is for a single consumer, this triggered signal indicates a Point of Consumption (PoC) and that the pharmaceutical product has reached the correct destination. In an embodiment, the electronic device further comprises a positioning system for determining the geographical location of the electronic device. This may be the position data utilized during the transport of the package in real time, e.g. via cellular triangularization calculation, and the position data indicating the position where the package is opened.

[0044] In an embodiment, the electronic device is selected from: a tracking device configured to track the position of the package and thus the asset in real time and share the real time position data with an external control computer, or a logger device containing sensor for measuring an environmental related parameter of the asset such as, but not limited to, temperature, humidity, tilt angle, shock, light intensity just to mention few and sharing the measurement data together with the position of the logger device in real time. The electronic device further comprises the light source.

[0045] The tracker or logger may comprise a re-chargeable power source which may be an ultra-thin and bendable battery which make is possible to have the electronic device few millimetres thick when at least part of the remaining electrical components include Printed Circuit Board (PCB). As an example, the processor and at least some of the remaining components and the communication module are arranged on the PCB.

[0046] In an embodiment, the light event detection device further comprises a screen-off structure placed between the light source and the light detector configured to screen off between the light source and the light detector such that the light detected by the light detector is essentially the reflected light from the lid. It is thus ensured that no light “contamination” between the light source and the light detector is present and that the light received by the light detector is solely the reflected light for the lid of the package.

[0047] In general, the various aspects of the invention may be combined and coupled in any way possible within the scope of the invention. These and other aspects, features and / or advantages of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0048] LIST OF EMBODIMENTS

[0049] 1. A method of operating a light detection system configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed, comprising: • detecting, subsequent to closing the package, incoming light intensity in the closed package (201),

[0050] • utilizing the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window (202),

[0051] • setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window (203), wherein the method further comprises:

[0052] • setting the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered where it is determined if the lid has been opened or not, where in case the potential box opening event indicates that the lid has not been opened (204),

[0053] • setting the light detection system to a second low energy mode (205), and

[0054] • utilizing the subsequent detected light intensity in determining a second upper-threshold light intensity level and a second lower-threshold light intensity level (206), and

[0055] • utilizing the second upper-threshold light intensity level and the second lower-threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window (207).

[0056] 2. The method according to embodiment 1, wherein step of setting the light detection system to a higher energy mode when a detected light intensity is detected to be above the first upperthreshold light intensity level comprises:

[0057] • emitting a light to an inner side on the lid of the package,

[0058] • detecting reflected light from the lid,

[0059] • processing the detected reflected light, and

[0060] • comparing the processed light with a pre-defined reference indicator when determining if the lid has been opened. 3. The method according to embodiment 2, wherein the emitted light is emitted with a predefined frequency, where the pre-defined reference indicator includes light intensity threshold, and where the step of determining if the package has been opened includes,

[0061] • comparing the light intensity difference between detected reflected light from the lid and in the absence of reflected light where the light source is turned off, where if the light intensity difference is above the light intensity threshold the package is determined to be opened via the lid.

[0062] 4. The method according to any of the preceding embodiments, further comprising triggering a signal event if the package is determined to be opened via the lid, and instructing a transmitter comprised in the electronic device to transmit the signal event to an external control computer.

[0063] 5. The method according to any of the preceding embodiments, wherein the step of utilizing the detected light intensity to determine a first / second upper-threshold light intensity level and a first / second lower-threshold light intensity level comprises defining a multiplication constants or variables a and P, where a<l and P>0, where the first / second upper-threshold light intensity level is when P is multiplied with the detected light intensity, and where the first / second lower-threshold light intensity level is when a is multiplied with the detected light intensity.

[0064] 6. The method according to any of the preceding embodiments, wherein the asset selected from: pharmaceutical product, food or beverages, and where the light source, light detector and the processor are an integral part of a tracking or logger device configured to track the position of the asset in real time during transport from an origin location to a destination location.

[0065] 7. The method according to any of the preceding embodiments, wherein the second lower energy mode is the same as the first lower energy mode.

[0066] 8. The method according to any of the preceding embodiments, wherein the second upperthreshold light intensity level and the second lower-threshold light intensity level and thus the second reference light intensity window is different from the first upper-threshold light intensity level and the first lower-threshold light intensity level and thus is different from the first reference light intensity window.

[0067] 9. A system (500) for operating a light detection system configured to detect if a light event detected in a closed package (513) having a lid (509) and containing an asset (506) is caused by opening the lid of the package or by ambient light entering the package when the package is closed, comprising:

[0068] • a light detector (502) for detecting, subsequent to closing the package, incoming light intensity in the closed package,

[0069] • a processor (504) configured to: o utilizing the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window, o setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window, o setting the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered where it is determined if the lid has been opened or not, where in case the potential box opening event indicates that the lid has not been opened, o setting the light detection system to a second low energy mode, and o utilizing the subsequent detected light intensity in determining a second upperthreshold light intensity level and a second lower-threshold light intensity level, and o utilizing the second upper-threshold light intensity level and the second lower- threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window.

[0070] 10. The system according to embodiment 9, wherein the low energy mode is where the processor is in sleep-mode, wherein the light detector is configured to activate the processor to be in activation-mode when the detected light intensity is detected to be above the first upper-threshold light intensity level.

[0071] 11. The system according to embodiment 9 or 10, further comprising a logger device (501) configured to be placed into the package and to measure at least on environmental parameter of the asset, where the light detector (502) and the processor (504) are comprised in the logger device.

[0072] 12. The system according to embodiment 11, wherein the logger device further comprises a light source (511), wherein step of setting the light detection system to a higher energy mode when a detected light intensity is detected to be above the first upper-threshold light intensity level comprises:

[0073] • emitting, by the light source, a light to an inner side on the lid of the package,

[0074] • detecting, by the light detector, reflected light from the lid,

[0075] • processing, by the processor the detected reflected light, and

[0076] • comparing, by the processor, the processed light with a pre-defined reference indicator when determining if the lid has been opened.

[0077] 13. The system according to embodiment 11, where the logger device further compris4e a screen-off structure 712 placed between the light source and the light detector configured to screen off between the light source and the light detector.

[0078] BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Embodiments of the invention will be described, by way of example only, with reference to the drawings, in which

[0080] Figure 1 shows a prior art light detection device,

[0081] Figures 2 shows a flowchart of a method according to the present invention,

[0082] Figure 3 depicts graphically a light simulated measurements simulating different ambient light where a package may be moved to different areas within a storage space,

[0083] Figure 4 shows a flowchart of an embodiment of method according to the present invention, Figures 5 and 6 depict graphically implementation of the method discussed in relation to figure 4, and

[0084] Figure 7 shows the logger device depicted in figures 5 and 4.

[0085] DESCRIPTION OF EMBODIMENTS

[0086] Figure 2 shown a flowchart of a method according to the present invention for operating a light detection system configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed. The package may as an example include, but is not limited to, any type of a boxes such as folding cartons, rigid boxes made of cardboard, corrugated boxes which may be made of fluted paper and have high strength and durability.

[0087] In a first step (SI) 201, after closing the package, incoming light intensity is detected in the closed package. This may be done using a logger device or a tracking device that is placed inside the box, and where the logger device comprises a processor and a light detector that detects the incoming light.

[0088] In a second step (S2) 202, the detected light intensity is utilized to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window. This may in one embodiment be done by defining a multiplication variables a and P, where 0<a<l and P>1, where the first / second upper-threshold light intensity level is when P is multiplied with the detected light intensity, and where the first / second lower-threshold light intensity level is when a is multiplied with the detected light intensity.

[0089] In a third step (S3) 203, the light detection system is set and maintained in a first low energy mode while the detected light intensity is within the first reference light intensity window. This could as an example be a scenario where the package is located where the ambient light is similar and where the ambient light variations are small.

[0090] In a fourth step (S4) 204, the light detection system is set to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered where it is determined if the lid has been opened or not. The step of determining if the lid has been opened or not, which will be discussed in more details in relation to flowchart in figure 4, may as an example be where the package is moved from a storage space to outdoors or close to a window, where the light intensity is much higher.

[0091] In a fifth step (S5) 205, if the potential box opening event indicates that the lid has not been opened, the light detection system is set to a second low energy mode. The first and second low energy mode may be understood as an energy mode where the processor of the logger device is in a “sleep” mode.

[0092] In a sixth step (S6) 206, the subsequent detected light intensity is utilized in determining a second upper-threshold light intensity level and a second lower-threshold light intensity level.

[0093] In a seventh step (S7) 207, the second upper-threshold light intensity level and the second lower-threshold light intensity level is utilized in dynamically updating the first reference light intensity window to a second reference light intensity window. Accordingly, by dynamically changing the reference light intensity window in this way the likelihood of unnecessary wakeups is minimized because the second reference light intensity window is adapted to the new ambient light intensity. This could as an example be where the closed package is moved from an area where the light intensity is low, such as a room with no window, to an area where the light intensity is high, such as next to window, or vice versa.

[0094] Figure 3 depicts graphically simulated light measurements, simulating different ambient light where a package may be moved to different areas within a storage space. An example of several different light intensity windows 301-304 is shown, which are dynamically updated as discussed in relation to the flowchart in figure 2.

[0095] Figure 4 shows a flowchart of an embodiment of step S4 discussed in relation to figure 2 where the light detection system is set to a higher energy mode by activating the processor when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level.

[0096] In a first step (S’ 1) 401, a light is emitted to an inner side on a lid of the closed package. The light may be emitted by a light source such as a light emitting diode (LED).

[0097] In a second step (S’2) 402, the light reflected from the lid of the package is detected by a light detector, such as in the logger or a tracking device. In a third step (S’3) 403, the detected reflected light is processed by a processor, such as in the logger or a tracking device.

[0098] In a fourth step (S’4) 404, the processed light is compared with a pre-defined reference indicator when determining if the lid has been opened.

[0099] In an embodiment, the processor is configured to instruct the light source to emit light with a pre-defined frequency, where the pre-defined reference indicator includes a light intensity threshold, and where the step of determining if the package has been opened is based on comparing the light intensity difference between detected reflected light from the lid and in the absence of reflected light, where if the light intensity difference is above the light intensity threshold the package is determined to be opened via the lid.

[0100] The step of emitting the light to the inner side on a lid of the closed package includes emitting light with a pre-defined frequency pattern and where the pre-defined reference indicator includes light intensity having the pre-defined frequency pattern. Accordingly, the step of determining if the package has been opened is based on comparing detected frequency pattern of the detected reflected light with the pre-defined frequency pattern, where in case of non-match the package is determined to be opened via the lid.

[0101] Based on the above, if it is determined that the package has been opened the processor triggers a signal event that the package has been opened and the signal event is transmitted to an external control computer.

[0102] Figures 5 and 6 depict a system 500 according to the present invention showing a package 513 having a lid 509, where figure 5 shows the lid package in closed position and figure 6 shows the lid of the package in open position.

[0103] Placed in the package is an electronic device 501 such as a tracker that tracks the position of the package preferably in real time where it regularly transmits position data to an external computer, or a logger device that may additionally to tracking the position measure environmental related parameter such as the temperature in the package and transmit it to the external control computer in real time.

[0104] The electronic device 501 is placed on an asset 506 where the electronic device comprises a light source 511, a light detector 502 and a processor 504 that controls the light source and the light detector, where the asset may as an example be a sensitive pharmaceutical product. The light source 511, which may be a part of the electronic device, is configured to emit light to an inner side of the lid 509, and the light detector 502 detects the reflected light 512, where the detected reflected light is processed by the processor 504 that compares it with a predefined reference indicator.

[0105] As depicted here, an additional small portion 510 of ambient light 508 enters the interior of the package 513. This small portion may e.g. enter via a small crack in the lid or because the lid is not sufficiently tight and / or thick.

[0106] As discussed previously in relation to figure 4, the reference indicator includes a light intensity threshold, where if the light intensity difference between detected reflected light from the lid and in the absence of reflected light (between these light emitting intervals) is above this light intensity threshold the package is determined not to be opened as shown in figure 5. Thus, this extra light portion 510 does not cause a false alarm.

[0107] Another alternative discussed in relation to figure 4, that is much less sensitive to ambient light, is to use the pre-defined frequency pattern as the reference indicator, where if the detected frequency pattern does match this pre-defined frequency pattern the box is determined not to be opened.

[0108] Both these methods may also be used simultaneously, where if the light intensity difference is above the light intensity threshold and if the detected frequency pattern matches this pre-defined frequency pattern the box is determined not to be opened.

[0109] Figure 6 shows where the lid 509 has been opened, and where the light 612 emitted by the light source 511 leaves the package 513. If the light intensity difference between detected reflected light from the lid and in the absence of reflected light is below the light intensity threshold the package is determined to be opened. Also, this will be reflected in a non-match in the detected frequency pattern.

[0110] In the embodiment shown here, the processor triggers a signal event 507 and instructs the transmitter 503 to transmit the signal event to an external control computer 505.

[0111] Figure 7 shows the logger device depicted in figures 5 and 6, further comprising a screen- off structure 712 placed between the light source and the light detector configured to screen off between the light source and the light detector such that the light detected by the light detector is essentially the reflected light from the lid.

[0112] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

CLAIMS1. A method of operating a light detection system comprising a light detector, a light source and a processor for controlling the light detector and the light source, where the light detection system is configured to detect if a light event detected in a closed package having a lid and containing an asset is caused by opening the lid of the package or by ambient light entering the package when the package is closed, where the method comprises:• detecting, by the light detector, subsequent to closing the package, incoming light intensity in the closed package (201),• utilizing, by the processor, the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window (202),• setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window (203), wherein the method further comprises:• setting, by the processor, the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered, where at the higher energy mode it is determined if the lid has been opened or not by means of: o emitting, by the light source, a light to an inner side on the lid of the package, o detecting, by the light detector, reflected light from the lid, o comparing the detected light intensity with a pre-defined reference indicator, where in case the comparing results in that the lid has not been opened (204),• setting the light detection system to a second low energy mode (205),• utilizing the subsequent detected light intensity in determining a second upper-threshold light intensity level and a second lower-threshold light intensity level (206), and• utilizing the second upper-threshold light intensity level and the second lower-threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window (207).

2. The method according to claim 1, wherein the first low energy mode is a mode where the processor is in sleep-mode.

3. The method according to claim 2, wherein the second low energy mode is the same as the first low energy mode.

4. The method according to any of the preceding claims, further comprising, in case the comparing results in that the lid has not been opened, switching the light source off.

5. The method according to any of the preceding claims, wherein the emitted light is emitted with a pre-defined frequency, where the pre-defined reference indicator includes light intensity threshold, and where the step of determining if the package has been opened includes,• comparing the light intensity difference between detected reflected light from the lid and in the absence of reflected light where the light source is turned off, where if the light intensity difference is below the light intensity threshold the package is determined to be opened via the lid.

6. The method according to any of the preceding claims, further comprising triggering a signal event or inventory related event if the package is determined to be opened via the lid and transmit the signal event to an external control computer.

7. The method according to any of the preceding claims, wherein the step of utilizing the detected light intensity to determine a first / second upper-threshold light intensity level and a first / second lower-threshold light intensity level comprises defining a multiplication constants or variables a and P, where 0<a<l and P>1, where the first / second upper-threshold light intensity level is when P is multiplied with the detected light intensity, and where the first / second lower-threshold light intensity level is when a is multiplied with the detected light intensity.

8. The method according to any of the preceding claims, wherein the asset is selected from: pharmaceutical product, food or beverages, and where the light source, light detector and theprocessor are an integral part of a tracking or logger device configured to track the position of the asset in real time during transport from an origin location to a destination location.

9. The method according to any of the preceding claims, wherein the second upper-threshold light intensity level and the second lower-threshold light intensity level and thus the second reference light intensity window is different from the first upper-threshold light intensity level and the first lower-threshold light intensity level and thus is different from the first reference light intensity window.

10. A light detection system configured to detect if a light event detected in a closed package (513) having a lid (509) and containing an asset (506) is caused by opening the lid of the package or by ambient light entering the package when the package is closed, comprising:• a light detector (502) for detecting, subsequent to closing the package, incoming light intensity in the closed package,• a light source (511),• a processor (504) configured to: o utilizing the detected light intensity to determine a first upper-threshold light intensity level and a first lower-threshold light intensity level, where the resulting light intensity window is utilized as a first reference light intensity window, o setting and maintaining the light detection system in a first low energy mode while the detected light intensity is within the first reference light intensity window, o setting the light detection system to a higher energy mode when a subsequent detected light intensity is detected to be above the first upper-threshold light intensity level, the higher energy mode being an energy mode where a potential box opening event is triggered, where during the higher energy mode the light source emits light to an inner side on the lid of the package and the light detector detects reflected light from the lid, where the processor is further configured to: o comparing the detected light intensity with a pre-defined reference indicator where in case the potential box opening event indicates that the lid has not been opened, o setting the light detection system to a second low energy mode,o utilizing the subsequent detected light intensity in determining a second upperthreshold light intensity level and a second lower-threshold light intensity level, and o utilizing the second upper-threshold light intensity level and the second lower- threshold light intensity level in dynamically updating the first reference light intensity window to a second reference light intensity window.

11. The system according to claim 10, wherein the low energy mode is where the processor is in sleep-mode, wherein the light detector is configured to activate the processor to be in activation-mode when the detected light intensity is detected to be above the first upperthreshold light intensity level.

12. The system according to claim 10 or 11, further comprising a logger device (501) configured to be placed into the package and to measure at least on environmental parameter of the asset, where the light detector (502), the light source (511) and the processor (504) are comprised in the logger device.

13. The system according to any of the claims 10 to 12, where the logger device further comprises a screen-off structure (712) placed between the light source and the light detector configured to screen off between the light source and the light detector.

14. The system according to claim 12 or 13, where the logger device further comprises a memory, a communication module comprising a transmitter, and at least one sensor for measuring an environmental related parameter of the asset.

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