Flat display device

Abstract

The invention relates to a flat display device (100) having a flat grid frame and a flat LED circuit board, wherein the grid frame and the circuit board form a stack, wherein an arrangement of LEDs on the LED circuit board is adapted to a grid structure of the grid frame, and wherein the LEDs on the LED circuit board are able to be actuated individually and / or in groups such that the display device (100) is able to deliver different display images.

Description

[0001] Flat display device

[0002] The invention relates to a flat display device, in particular to support safety during forestry work.

[0003] For example, if tree felling is being carried out in a forest, it is necessary to cordon off the area in which the work is taking place. This is intended to prevent, in particular, innocent bystanders from being injured by falling branches or even toppling trees. Barriers, signs, banners, and barriers are used for this purpose. However, these measures do not always provide sufficient protection. For example, if you think of a warning sign in a forest, it can easily be overlooked. It also happens that passersby notice a sign but assume that it has simply been forgotten because they are unaware of any tree felling or other activities in the forest at that moment.

[0004] The invention is therefore based on the object of providing a display device which is highly unlikely to be overlooked and which also makes it clear that it was not found there accidentally, but that it indicates a real danger.

[0005] This problem is solved with the features of the independent claim.

[0006] Advantageous embodiments of the invention are specified in the dependent claims.

[0007] The invention consists of a flat display device with a flat grid frame and a flat LED circuit board, wherein the grid frame and the circuit board form a stack, wherein an arrangement of LEDs on the LED circuit board is adapted to a grid structure of the grid frame and wherein the LEDs on the LED circuit board can be controlled individually and / or in groups so that the display device can deliver different display images. The display device is therefore not a passive device, such as a sign or a banner, but is active in that it can deliver display images via a large number of LEDs. With sufficient light intensity from the LEDs, it is very unlikely that passers-by will overlook the display device. Furthermore, no passer-by would probably think that such a display device could accidentally be left standing in the forest.Rather, they take the display seriously and, on this basis, avoid entering a restricted area. The display images can be static, meaning they indicate a specific circumstance without change, such as "logging." The display images can also be dynamic, meaning they can change, thereby conveying different information. For example, the display images can replicate traffic signs prohibiting passage or crossing a border. It can also indicate that riding a horse into a restricted area is prohibited. The display device can also indicate video surveillance in the restricted area, especially if the display device can be coupled with other components that conduct such video surveillance. The display images can also be moving images.The grid frame can have several thousand regularly arranged grid openings, with an LED arranged in each of these openings after the grid frame and LED circuit board are joined together. Ideally, the LEDs are RGB LEDs so that they can illuminate in different colors. The grid openings can have identical or different shapes. It is preferred that all grid openings have the same shape. The grid openings can be rectangular, square, oval, circular, other polygonal, or even completely different shapes. To ensure good contrast between the display images, the grid frame is made of black acrylic glass. The color black is also preferred for the LED circuit board.

[0008] The invention is advantageously further developed in that the stack additionally comprises a film, wherein the components of the stack are stacked in the order (i) film, (ii) grid frame, (iii) circuit board. The film is preferably a polyester film, for example, with the specification "Autotex V200" and a thickness of 0.4 mm. In the finished state of the display device, the film forms the outermost layer and protects the display device against external influences. To simplify the manufacture of the display device and to ensure a reliable edge seal with regard to the penetration of foreign substances from outside, the film and grid frame are bonded at the edges with double-sided adhesive tape.

[0009] It's particularly useful if the film is back-printed with a grid whose grid constant corresponds to the grid constant of the grid frame. Ideally, the grid bars of the grid plate should lie exactly over the grid bars of the grid display on the film. The grid display on the film improves the contrast of the displayed images.

[0010] It is useful that the grid openings of the grid frame are larger than those of the grid display. This ensures that the grid openings in the frame are large enough to accommodate the individual LEDs. However, the visible grid openings are reduced by the smaller grid openings of the grid display on the slide, which further improves the contrast. For example, if the grid openings are square, the grid openings of the grid frame have a size of 7 mm x 7 mm, while the grid openings of the grid display on the slide can have a size of 5 mm x 5 mm.

[0011] A particular advantage is that the film, grid frame, and circuit board are encapsulated together, forming an LED package. The encapsulation of the grid frame and circuit board takes place in a mounting frame, which is removed after the encapsulation compound has hardened. This results in a stable LED package that already possesses several properties that protect the display device against external influences. The circuit board also contains an electrical interface to which the stranded wires of an outward-facing cable are soldered. This solder connection is created prior to encapsulation, so that the electrical connection between the cable and the circuit board is also encased in the encapsulation compound.

[0012] Usefully, the circuit board is designed to be multi-part. For example, the LED circuit board can consist of four individual parts, with one of these sub-boards acting as the master circuit board, while the remaining three sub-boards function as slave circuit boards. The four circuit boards are soldered together for mechanical stability. The electrical connection between the sub-boards thus simultaneously provides the necessary mechanical stability, eliminating the need for additional mechanical connections between the sub-boards.

[0013] The invention is further developed in a particularly useful manner in that the stack additionally comprises a housing pot base of a housing pot, with a housing pot wall projecting from the housing pot base. The components of the stack are stacked in the order (i) foil, (ii) grid frame, (iii) circuit board, (iv) housing pot base. In this way, the LED package is exposed only on the foil side, while the other sides of the LED package are surrounded by the housing pot.

[0014] Here, too, it is useful for the LED package and the housing pot to be encapsulated. For this purpose, the LED package is placed in the housing pot, aligned parallel to the housing pot base, and adjusted with a constant or nearly constant distance between the edge of the LED package and the housing pot wall. The encapsulating compound is then introduced through the gap between the edge of the LED package and the housing pot wall. The LED package maintains a certain, preferably adjustable, distance from the housing pot base so that the encapsulating compound can be distributed over the entire surface of the housing pot base and the LED package.

[0015] Usefully, the housing cup is provided with at least one fastening device for the display device on the side facing away from the LED package. The housing cup, which can be manufactured with any desired rigidity, for example, from plastic or metal, thus offers the possibility of securely mounting the display device.

[0016] Another useful embodiment of the display device is designed in such a way that an ambient light sensor is provided. The ambient light sensor allows the brightness of the display device to be adjusted to the ambient light intensity. At night, a lower intensity is required than during the day.

[0017] The ambient light sensor is arranged in an opening in the grid plate. One conceivable variant is for the ambient light sensor to be arranged in one of the regular grid openings instead of one of the plurality of LEDs. However, the grid plate can also have a separate opening in the edge region for the ambient light sensor. Furthermore, it is advantageous that the display device can be coupled to an information sign unit via an electrical interface, with electrical signals for defining the display images of the display device being delivered from the information sign unit to the display device via the electrical interface. The display device therefore does not have to be equipped with any components via which an adjustment can be made.Rather, the display device can be supplied with electrical energy by an indicator unit, and all information for controlling the LED circuit board can also come from the indicator unit.Such an information sign unit is, for example, a device with at least one motion sensor which detects movements of objects in the surroundings of the information sign unit, and at least one signaling device which is suitable for outputting different optical and / or acoustic signals, wherein the type of the different optical and / or acoustic signals depends on whether the motion sensor has detected a movement of an object in the surroundings of the information sign unit, wherein the information sign unit is designed at least partially as a column defining a cavity with a first end and a second end, and wherein functional components of the information sign unit are arranged in the cavity. The column-like structure of the information sign unit, which this at least partially has, offers numerous advantages.A column is eye-catching and can be arranged practically anywhere without requiring excessive space. A column can provide a large hollow space in which the functional components of the information sign unit are arranged. The arrangement can be extremely variable because a hollow space in a column does not entail any particular restrictions regarding the shape and size of the functional components. In the context of the present disclosure, a column or a column-like shape is referred to when, with a corresponding arrangement, the vertical dimensions are significantly larger than the horizontal dimensions. For example, one can speak of a column when the vertical dimension is at least twice as large as the horizontal dimension, at least in sections. The column with its hollow space can, for example, be formed by a tube of any shape.According to a preferred embodiment, such a tube is at least partially cylindrical. This makes it possible to carry optical signals from an optical signaling device arranged in the tube out of the hollow space of the column, provided that the boundary of the hollow space is at least partially transparent. Transparency is also required in the area of ​​a motion sensor arranged in the column, provided that the motion sensor operates on an optical basis. According to a preferred embodiment, all functional components of the information sign unit can be accommodated in the hollow space of the column, so that they are protected against external influences, for example against weather influences and mechanical influences during assembly and dismantling of the information sign unit, as well as in the event of possible vandalism. It is particularly advantageous if an optical signaling device having a plurality of LEDs is provided in the hollow space.With modern LED technology, variable and intense effects can be created. The LEDs can have different colors, so that signals can be emitted in different ways based on a color selection. The LEDs can be controlled with different power levels, so that optical signals can have different intensities. Furthermore, LEDs operate with comparatively low power, so that a limited energy supply in the information sign unit, provided for example by a rechargeable battery, is sufficient for a long time. It is particularly preferable for the cavity at the first end of the column to be bordered by an acoustic signaling device. This arrangement of an acoustic signaling device is particularly useful when the cavity is hermetically sealed, in particular to protect the components arranged therein against external influences.The acoustic signaling device, such as a loudspeaker, is then attached to the end of the column, for example as the end of the cylindrical tube, so that sound can escape into the environment without being hindered by the otherwise hermetic seal of the cavity. A particular advantage is that a camera is arranged in the cavity, which serves as both a motion sensor and an image capture unit. Such a camera can therefore be active at all times or only when needed, emitting corresponding signals in the event of changes in its field of view, thus performing the function of a motion sensor. As soon as a change in the camera's field of view is detected, the camera can then also perform its other function, namely capture an image. The camera can perform its functions as a motion sensor and as an image capture unit even in the dark.It can be provided that the information sign unit is equipped not only with LEDs that emit light in the visible range, but also with infrared LEDs. This allows for permanent monitoring. Furthermore, it can be provided that the cavity is delimited by a heat sink at the second end of the column. Excess heat generated by the functional components within the cavity is efficiently dissipated via such a terminal heat sink, which, for example, forms an upper, flared end of the column-like structure. It can also be provided that a GPS antenna is provided at the second end of the column. Since the second end of the column preferably forms the upper boundary of the information sign unit during operation, a GPS antenna is particularly well positioned at this point, since the least interference with the reception and transmission of the GPS antenna is to be expected here.Such a GPS antenna communicates with a GPS module within the information sign unit so that the information sign unit can always be located. Another advantage is that the LEDs are arranged adjacent to the heat sink. Even though LEDs generally emit little heat compared to other light sources, cooling is required in this area when the light output is high. In this respect, the proximity of the heat sink to the LEDs is advantageous. The invention is further advantageously configured in that a controller unit is provided adjacent to the acoustic signaling device. From bottom to top, the functional components are arranged in the following order: acoustic signaling device, controller unit, lighting unit, heat sink. The camera is preferably positioned at the height of the controller unit.A rechargeable battery, provided it is provided within the cavity, can be positioned anywhere. At low outside temperatures, it is useful to keep the rechargeable battery at the highest possible temperature to extend the charging cycle. This can be achieved, for example, by directing heat released by other functional components within the cavity to the rechargeable battery when needed, particularly at low outside temperatures. This can be achieved with the aid of a small fan and / or variably adjustable, in particular automatically adjustable, air guide elements. A rechargeable battery heater can also be provided for the purpose of heating the rechargeable battery. The controller unit can, in particular, contain a Bluetooth interface and a WiFi interface.The structure of the information sign unit is further preferably designed such that an electrical interface is provided at the first end of the column. This first end of the column, which is preferably located at the bottom of the information sign unit during operation, offers the option of supplying electrical energy, be it from an external accumulator or for charging an internal accumulator. Furthermore, the electrical interface can also be designed as a data interface. Likewise, it can be provided that a mechanical interface for coupling the column to a support is provided at the first end of the column. Such a mechanical interface can have the form of a flange, so that the column can be fastened to a counter flange by means of screws. The mechanical interface can also be a component of a bayonet connection. A further advantage is that the support is a tripod with three feet.With such a tripod, the information sign unit can be positioned variably, particularly in terrain where uneven ground is often encountered. In this context, it is useful to have an anchoring device for at least one of the feet. Since the center of gravity of the column-like information sign unit, which is mounted on a tripod, is relatively high, anchoring can be advantageous, as this protects against the information sign unit being accidentally or intentionally knocked over, as well as against the information sign unit toppling over due to weather influences, particularly storms. The anchoring device is provided with a first base plate arranged parallel to the ground and a second leg plate arranged parallel to the leg, wherein the base plate and the leg plate are articulated to one another via a pivot axis.The relative pivoting of the leg plate and base plate allows anchoring on any surface, even uneven ones. Specifically, the base plate is designed to have a recess for the tripod foot to pass through, as well as a hole for a fastening anchor. The tripod foot therefore passes seamlessly through the base plate. A peg or ground screw, for example, can then serve as a fastening anchor. Furthermore, the leg plate can be designed to have a slotted hole for the variable attachment of one of the tripod feet. This provides further adjustment options for adverse terrain conditions, as the foot can be variably attached at different heights in the slotted hole in the leg plate.The invention further comprises a warning system having at least one mobile warning signal unit as defined above, as well as a central unit capable of receiving a signal transmitted via radio from the at least one warning signal unit and of outputting a signal thereon to a user of the central unit. The objects mentioned are primarily persons or groups of persons. However, they can also be other objects, such as animals, manned or unmanned vehicles, and manned or unmanned aircraft. In particular, if a person inadvertently enters a restricted area, they are warned by a visual and / or acoustic signal. This person will most likely then retreat. At the same time, a central unit is signaled via radio, for example via longwave radio, that the restricted area has been entered.Similarly, a signal can be given again once the person has left the restricted area. The system can also be effective if the person intentionally enters the restricted area. The acoustic and / or visual signaling can be so deterrent that any deliberate attempt to enter the restricted area is aborted, comparable to the effect of an alarm system on a residential building. Furthermore, if a signal is sent to the central unit that a person has entered the restricted area and the user of the central unit determines that there is no subsequent exit from the restricted area, the dangerous forestry work can be temporarily stopped, and the person can be searched for and brought to safety on this basis.Even if the warning system with its signaling device is suitable for emitting a visual and / or acoustic signal, it may sometimes be desirable for a signal not to be emitted even if the movement of an object in the vicinity of the warning sign unit is detected. In other words, the user of the warning system may wish for only a signal to be sent to the central unit. This way, the person approaching the warning sign unit will not know that they have been detected. This can be helpful, for example, in the arrest of criminals. Furthermore, in private areas, it may be undesirable to generate disruptive visual or acoustic signals in the vicinity of the warning sign unit. The warning sign unit can also be further developed so that signs or banners held by the warning sign unit are equipped with lighting. They can be illuminated, for example, by an LED border.This LED border can be operated continuously or flashing, whereby the operating mode - continuously or flashing - depends on whether an object has been detected. The optical signals in the area of ​​the information sign unit can also be movements of the information sign unit's components, for example movements of signs and / or banners. It is particularly useful that the information sign unit can detect the location of the object, and that the optical signal and / or the acoustic signal and / or the transmitted signal can be changed depending on the detected location. The person approaching the information sign unit can therefore be alerted early by the motion sensor, preventing them from entering the restricted area in the first place. In principle, signaling to the central unit is unnecessary in this case.As soon as it is determined that the person is crossing or has already crossed the border into the border area, a signal must be sent to the central unit. Furthermore, by changing the type of visual and / or acoustic signal, the person can be made aware that this is not just a warning, but that the person is now actually in the restricted area and therefore in danger of death. In principle, changing the signaling can always be useful when a critical change in the position of the object is detected. If the object comes closer to the border marked by the information signal unit, for example, the signaling can become more intense. It becomes particularly intense when the person enters the restricted area.Conversely, the signaling can become less intense if the person leaves the restricted area or moves away from the restricted area boundary into non-critical areas. Usefully, the central unit can be coupled to a communication unit located in the user's hearing protection, so that the warnings can be transmitted to the user via the hearing protection. The user of the central unit will typically be a forestry worker working alone, supervising several other forestry workers, or entrusted with the specific task of operating and using the warning system.Since hearing protection is often worn during forestry work, whether insulated hearing protection or hearing protection connected to a safety helmet, it can be difficult to alert the user of the central unit to a signal received by the central unit, especially if it is an audible signal. This is remedied by equipping the hearing protection with a communication device activated by the central unit. The user can hear a special signal through the hearing protection with the communication unit or even a spoken message, such as "Person in restricted area." Conveniently, the central unit communicates with the communication device of the hearing protection wirelessly, preferably via Bluetooth. Bluetooth-enabled hearing protection components are well known and available.Although the present invention is primarily explained using forestry work as an example, it can nevertheless also be used in numerous other environments. For example, it may be desirable to prevent or detect the access of persons to construction sites. It may also be useful to equip any other security areas with the warning system, for example in the healthcare sector. In preferred embodiments, the central unit is a mobile phone or can be coupled to a mobile phone. With regard to the communication of the central unit with a Bluetooth communication device of a hearing protector, the advantages are obvious, since mobile phones can easily be used for Bluetooth communication.It is also useful for the mobile phone to be equipped with an application that indicates on a display on the mobile phone that the movement of an object in the vicinity of the warning signal unit has been detected. The application (an app) on the mobile phone thus shows all events in the restricted area, and the events can also be saved so that it is possible to later trace what happened in the restricted area and at what time. According to a further useful embodiment, several warning signal units are provided and the type of information issued by the central unit depends on which warning signal unit sent a signal. This offers decisive advantages, especially in large restricted areas. On this basis, the user of the central unit knows from where a person is approaching and can take appropriate action.Furthermore, it is useful for the warning sign unit to include a recognition module capable of detecting at least one property of the object. The property of the object can, for example, be authorization to enter the restricted area. For example, a forestry worker can be equipped with an RFID chip, which is registered by the recognition module in the warning sign unit. An alarm can then be suppressed, as it can be assumed that the forestry worker, identified by the RFID chip, knows how to move and behave in the restricted area. Even if an alarm is not triggered, a signal can still be sent to the central unit. A mobile phone display would then no longer read "Person in restricted area" but rather "Authorized person in restricted area." The user of the central unit then has nothing further to do.The recognition module can also include a facial recognition device, so that it can actually be determined that the person entering the restricted area is potentially an authorized person. Conversely, certain individuals can also receive "special treatment." If the central unit is to be alerted that certain individuals are entering the restricted area, the facial recognition features of these individuals can trigger special messages to the central unit, for example, "Forest ranger Meier enters restricted area." The recognition module can also be or include a body temperature detection device. Thus, the warning unit can react differently to individuals with a normal body temperature than to individuals with an elevated body temperature. This can serve to protect against infection, namely if one wants to prevent infected individuals who frequently have an elevated body temperature from entering a restricted area.For example, for individuals with a normal body temperature, a message can be suppressed from being issued at the central unit. Or a message such as "Non-infected person entering restricted area" can be issued at the central unit. However, if the individual has an elevated body temperature, a message such as "Potentially infected person entering restricted area" can be issued at the central unit. For individuals with a normal body temperature, it may be possible to dispense with the output of visual and / or acoustic signals at the warning unit. However, for individuals with an elevated body temperature, such signals can be output at the warning unit. However, it may also be advisable not to issue signals at the warning unit in the case of potentially infected individuals, particularly for data protection reasons.The detection module of the warning signal unit can also be adapted to interact with an application on a mobile phone or with a separate device worn by the person approaching the warning signal unit. The application or device can, for example, store whether the person in question has been in proximity to other people known to be infected. Based on this, different responses can be initiated. As with the detection of body temperature, different messages can be output to the central unit. Likewise, as with the detection of body temperature, different signals or no signals can be output to the warning signal unit.The sign unit may have a variety of other properties and features, such as image processing based on neural networks for detecting objects such as faces, infrared LEDs to ensure operation of the sign unit at night, and a LIDAR module for detecting objects at a great distance.

[0018] The invention will now be explained by way of example with reference to the accompanying drawings.

[0019] Figure 1 shows a plan view of a forest with a restricted area and a warning system according to the invention.

[0020] Figure 2 shows the equipment of a user of the warning system.

[0021] Figure 3 shows schematically the functional structure of an information sign unit.

[0022] Figure 4 shows schematically the structural properties of an information sign unit.

[0023] Figure 5 is an illustration of a particularly preferred indicator unit.

[0024] Figure 6 shows the information sign unit according to Figure 5 on a tripod.

[0025] Figure 7 is a perspective view of an anchoring device with a foot of a tripod.

[0026] Figure 8 is another perspective view of an anchoring device with a foot of a tripod.

[0027] Figure 9 is a flowchart of a method for operating a warning system. Figure 10 is a flowchart of an image recognition method.

[0028] Figure 11 shows a perspective view of a lattice frame and components to be connected to it.

[0029] Figure 12 shows a perspective section through the stack of film and grid frame.

[0030] Figure 13 shows an oblique plan view of a lattice frame.

[0031] Figure 14 is a perspective view of an LED circuit board and components to be connected to it.

[0032] Figure 15 shows an oblique top view of an LED circuit board.

[0033] Figure 16 shows an oblique top view of a potted system consisting of foil, grid frame, LED circuit board and mounting frame.

[0034] Figure 17 shows a perspective view of the removal of the LED package from the mounting frame.

[0035] Figure 18 shows a perspective view of the LED package and a housing pot.

[0036] Figure 19 shows a top view of the display device.

[0037] Figure 20 shows a perspective view of the display device.

[0038] Figure 21 shows a plan view of the back of the display device.

[0039] Figure 22 shows a perspective view of the display device.

[0040] Figure 23 shows various side and sectional views of the display device. Figure 24 shows a combination of a sign unit and the display device.

[0041] For a better understanding of the present invention, the technical environment in which the display device according to the invention is preferably used is first described with reference to Figures 1 to 10. Starting in Figure 11, the display device itself is then explained.

[0042] Figure 1 shows a plan view of a forest with a restricted area and a warning system according to the invention. A forest area with numerous trees 48 is shown. Part of this forest area is designated as a restricted area 14, wherein the restricted area 14 is surrounded by a boundary 12. Several information sign units 10 are arranged on this boundary 12 or in the vicinity of this boundary 12. In the present example, the information sign units are located at corners of the boundary 12. However, this is not mandatory. It is also possible for additional information sign units to be installed on the straight sections of the boundary 12. Furthermore, information sign units do not necessarily have to be arranged at the corners of the restricted area 14. What is important is that, measured against the length of the boundary 12, a sufficient number of information sign units 10 are arranged.In the present example, each information sign unit 10 has a signaling device 20 for emitting an acoustic signal, for example a loudspeaker, and a signaling device 22 for emitting an optical signal, for example an LED. It is not necessary to provide both an acoustic and an optical signaling device. The information sign units 10 can also be provided with one of the aforementioned signaling devices. The user 26 of a central unit 24 and the central unit itself are located within the restricted area 14. As soon as an object 18, that is to say in particular a person, approaches an information sign unit 10, this information sign unit 10 emits an acoustic and / or optical signal. At the same time, a signal is transmitted to the central unit 24, for example in the longwave range.The user 26 of the central unit 24 is thus informed that an object 18 is approaching the restricted area, is currently crossing the boundary 12 of the restricted area 14, or has already crossed it. The notification given to the user 26 of the central unit 24 can contain information about whether an object 18 is hidden behind the object 18 that is authorized or unauthorized to enter the restricted area 14. Furthermore, the user 26 of the central unit 24 can be informed about which of the indicator units 10 has detected the object 18. In this case, a restricted area 14 in a forest is described. The system can equally be used to monitor construction sites, avalanche slopes, and shooting ranges, to name just a few other examples.

[0043] Figure 2 shows the equipment of a user of the warning system. In this preferred case, the central unit 24 is a commercially available mobile phone 32 that is Bluetooth-enabled. The user 26 of the central unit 24 or of the mobile phone 32 wears hearing protection 30 that has a communication unit 28. This communication unit 28 is also preferably Bluetooth-enabled. In this way, the mobile phone 32 can provide the user 26 wearing the hearing protection 30 with an acoustic signal or an acoustic message about the activation of one of the warning signal units. Simultaneously or alternatively, information can be shown on the display of the mobile phone 32 that provides more detail about what is currently happening or what has happened at some point in time. The user of the warning system can therefore be notified acoustically and / or visually.It is also possible to notify the user, for example, by vibration, or generally by tactile means.

[0044] Figure 3 schematically shows the functional structure of a sign unit. It depicts a sign unit 10 with its main functional components. A central controller 50 is coupled to an acoustic signaling device 20 and an optical signaling device 22. Furthermore, a motion sensor 16 for detecting an object in the vicinity of the sign unit 10 is connected to the controller. As a further component, the sign unit 10 contains a recognition module 34, which is capable of distinguishing between objects based on their properties—for example, an object that is permitted to enter the restricted area from one that is not permitted to enter the restricted area. The sign unit 10 can also contain a camera 36, ​​which is also connected to the controller 50.Another component that can be connected to the controller 50 in conjunction with the information sign unit 10 is a GPS antenna 38. This can be used to determine the position of the information sign unit 10 at any time. In addition to simply locating the information sign unit 10 via the GPS antenna 38, the GPS system can also be used in rescue operations. If, for example, an accident occurs during forestry work, rescue workers can reach the scene of the accident promptly and accurately using the coordinates determined via the GPS system. The GPS system can also be used in connection with surveying work, particularly when several information sign units 10 are networked together. The accuracy of such surveying information based on GPS coordinates determined by the individual information sign units 10 can be sufficient for many purposes. The controller 50 is also connected to a transmitter 52.The indicator unit communicates with the central unit via this transmitter 52. In addition to the transmitter 52, a receiver can also be provided so that, for example, the acoustic and / or optical signaling of the indicator unit 10 can be stopped or otherwise prevented by the central unit. The receiver is not shown here. Instead of a transmitter 52 and a receiver, a transceiver can also be provided, which performs both sending and receiving. Ultimately, all data or a selection of the data acquired by the indicator unit 10 can be sent to the central unit via the transmitter 52 or the transceiver for information purposes or for storage.

[0045] Figure 4 schematically shows the structural features of a sign unit. A tripod 40 supports a tube 42, to which information signs can be attached, for example, information sign 44. These signs warn people approaching the sign unit 10 not to enter a restricted area. A banner 46 can be stored within the tube 42, which can also be extended using the sign unit 10. This allows for an even larger warning of a restricted area.

[0046] Figure 5 is an illustration of a particularly preferred information sign unit 10. The information sign unit 10 has a column-like structure. The column 50 comprises an acoustic signaling device 22 at a first end. The second end of the column 50 is formed by a heat sink 54. This heat sink 54 has a plurality of ribs 80. An O-ring 82 is attached to the heat sink 54 as edge protection. A GPS antenna 38 is located at the uppermost point of the column 50. An at least partially transparent cylindrical tube, for example made of acrylic glass or another transparent material, is arranged between the acoustic signaling device 22 and the heat sink 54, which tube defines a cavity 48.The cavity 48 houses functional components of the indicator unit 10, namely, in particular, several LED arrays with a plurality of LEDs 52 that emit light of different wavelengths, optionally in both the visible and infrared ranges. For example, in the visible range, LEDs 88, 90, 92 in the colors orange, white, and red are provided alongside infrared LEDs 94. The LEDs 52 are arranged along the entire circumference of the column 50, which is cylindrical in the present example. LED driver modules 84 are located below the LEDs 52. The LED driver modules 84, together with the LEDs 52, form an optical signaling device 20. In the cavity 48 of the column 50, below the LED driver modules 84, there is a controller unit 56 including a Bluetooth and WiFi interface, as well as an input / output card 86. At the same height of the column 50 is the motion sensor 16, which is designed here as a camera 36.The camera has a field of view of approximately 170 degrees. To expand the field of view, multiple cameras can be arranged around the circumference of the column 50. In addition to its function as a motion sensor 16, the camera 36 can capture images, preferably with both visible and infrared light. This means that the camera 36 can also provide images in the dark, as long as the surveillance area of ​​the information sign unit is illuminated by the aforementioned infrared LEDs. Preferably, the images captured by the camera 36 are fed to a neural network in order to decide whether relevant objects have been detected by the camera 36. For example, if one is only interested in detecting people, the neural network can be configured such that the corresponding information functions of the information sign unit only become active when a person has been detected by the camera.Accordingly, in other cases, the neural network can also be designed to be sensitive to other objects, for example, animals or even specific animal species. Animal detection, particularly wild animals or livestock, can be useful for counting and / or monitoring them with the indicator unit 10. Images captured by the camera 36 can be stored and / or sent, depending on the desired purpose. Sending is preferably done via the aforementioned Bluetooth and Wi-Fi interfaces.

[0047] Equipping the warning sign unit 10 with a conventional camera 36 may be sufficient if only a limited surveillance area is to be monitored, for example, a surveillance area up to 10 meters away from the camera 36. To significantly expand the surveillance area, a LIDAR module can be integrated in addition to the camera. LIDAR is a system for optical distance and speed measurement. This allows objects to be located even when they are still at a distance of, for example, 50 meters from the warning sign unit 10. Measures to deter or detect objects can therefore be taken much earlier, as they approach the warning sign unit 10.The electrical interface 62 provided on the information sign unit 10 can be used to transfer energy required for the operation of the information sign unit 10. For example, a rechargeable battery provided in the information sign unit 10 can be charged via the electrical interface 62. If an external rechargeable battery is used, the energy provided by the rechargeable battery can be made available to the active components of the information sign unit 10 via the electrical interface 62. An internal rechargeable battery is preferable in terms of the compactness of the overall system. Such a rechargeable battery is preferably arranged in an area of ​​the information sign unit or the cavity 48 of the information sign unit 10, to which a large amount of heat generated during operation can be supplied if necessary. This extends the charging cycle of the rechargeable battery at low outside temperatures.Additionally or alternatively, a heater can be provided for the accumulator. The electrical interface 62 can also be used to transmit data, whereby the aforementioned wireless interfaces (Bluetooth and / or WiFi) of the controller unit 56 are, of course, generally available for this purpose. If no data transmission option is desired independent of the wireless interfaces and no external electrical power is to be supplied to the system, the electrical interface 62 is unnecessary. In this case, removable accumulators can be used. These are simply replaced when needed. For example, it is possible to design the indicator unit 10 so that it can be opened, for example by removing the heat sink 54. This could be screwed onto the transparent tube so that the heat sink 54 can be unscrewed. If a removable accumulator is arranged in the then exposed area, it can be easily replaced.

[0048] The camera 36 or the multiple cameras of the information sign unit 10 can be housed invisibly within the information sign unit 10. For example, a concealing area 96 of the column 50 can be mirrored for this purpose, so that no light can pass from the inside to the outside in this concealing area 96, while light from the outside to the inside easily reaches the camera 36. Therefore, for a person encountering the information sign unit 10, it is initially not apparent that an image of it could be captured. Even if the person is aware that images can be captured, they still do not know where the camera is located. The now frequently observed attempts to deactivate cameras using spray paint are therefore rarely successful. The camera 36 can also be "hidden" in other ways.For example, the wall bounding the cavity 48 could be designed to be non-transparent in a large area around the camera 36 or the multiple cameras, but within the non-transparent area, a plurality of regularly or irregularly arranged transparent sub-areas are provided, each of which is only large enough to allow the camera lens to "see through." Camera lenses are arranged behind only one or some of these transparent sub-areas. Therefore, a person who wants to deactivate the camera 36 or the cameras by spraying paint does not know where to place the spray paint. The person may not even realize that there are openings for cameras behind the arrangement of transparent areas in a larger non-transparent area.The lamination area 96 can therefore be designed in various ways, according to the above examples by a mirror coating or by an arrangement of transparent and non-transparent partial areas.

[0049] It may also be desirable for a person approaching the sign unit to be informed that a camera is present. It would therefore be conceivable for the image capture process by camera 36 to be accompanied acoustically by a sound that the person nearby perceives as a camera being triggered.

[0050] The basic monitoring operation of the warning signal unit 10 is preferably conveyed by a comparatively low-intensity and non-threatening signal, for example, a white or orange optical signal of comparatively low intensity. If an object approaches and is identified as a critical object, the optical signaling can be different and / or more intense. At the same time, an acoustic signal can be emitted, for example, a siren signal or the barking of a dog. It is also possible for the warning signal unit 10 to address the approaching person using a human voice. This initially attempts to deter the approaching person, so that, ideally, they simply turn around.If this fails, so that the person's position becomes even more critical, i.e., they approach the border of the restricted area or even cross the border, the alarm will be intensified again at that point, and images will be saved or sent to the central unit. Along with any information sent to the central unit, an identifier for the respective warning unit 10 is also transmitted. The user of the central unit therefore knows exactly which warning unit 10 the information originated from. Other useful features of the warning unit 10 can include satellite phone capability, enabling expanded communication with the warning unit 10, particularly for data transmission.

[0051] For the purpose of theft protection, the warning signal unit 10 can also include an acceleration sensor. When the acceleration sensor is activated, a signal specifically intended for this purpose can be transmitted to the central unit.

[0052] The entire software on the basis of which the controller unit 56 operates can be updated regularly, either via an app installed on the central unit or another (mobile) device or via a data interface which, for example, is part of the electrical interface 62.

[0053] A mechanical interface 58 is also provided in the lower area of ​​the column 50. The column can be mounted to a support via this mechanical interface 58, for example, a flange or a component of a bayonet coupling.

[0054] Figure 6 shows the information sign unit 10 according to Figure 5 on a tripod. Here, the information sign unit 10 is mounted on a tripod 40 via the mechanical interface 48. The tripod 40 has three feet 64, corresponding to the number of legs. The tripod 40 is height-adjustable, so that the information sign unit 10 can stand securely even on uneven terrain.

[0055] Figure 7 is a perspective view of an anchoring device 66 with a foot 64 of a tripod 40. Figure 8 is another perspective view of an anchoring device 66 with a foot 64 of a tripod 40. In order to prevent the information sign unit 10 from tipping over, the feet 64 of the tripod 40 can be fixed to the ground by means of anchoring devices 66. It may be sufficient to provide an anchoring device 66 on only one foot 64. In particularly difficult circumstances, anchoring devices 66 can be attached to all feet 64. An anchoring device 66 comprises a base plate 68 and a leg plate 70. The base plate 68 and the leg plate 70 are pivotally connected to one another via a pivot axis 74. The base plate 68 has a recess 72 through which a foot 64 can pass.Furthermore, a hole 76 is provided in the base plate 68 through which an anchoring device, such as a peg or ground screw, can be driven into the ground. The foot 64 is attached to the leg plate 70 via an elongated hole 78. This allows the foot 64 to be mounted on the anchoring device 66 at different heights.

[0056] Figure 9 is a flowchart of a method for operating a warning system. First, in step S01, the monitoring function is activated. Preferably, in step S02, a relatively low-intensity but nevertheless sufficiently conspicuous optical monitoring signal is activated. If a critical object is then detected in step S03, a first alarm is activated. This occurs in step S04. Such an alarm can be triggered by changing the optical signal and / or by an acoustic signal. However, as long as no critical object is detected in step S03, the optical monitoring signal continues to be emitted. After the first alarm is activated in step S04, a check is carried out in step S05 to determine whether the critical object is still being detected. Ideally, this is not the case. The warning sign unit has then fulfilled its particularly desired deterrent function.The method then proceeds to step S06, where the first alarm is deactivated again, with the optical monitoring signal subsequently being activated again in step S02. However, if it is determined in step S05 that the critical object is still being detected, a further check is performed in step S07. This is where it is determined whether there has been a critical change in the position of the detected object. If this is not the case, a further check is performed to determine whether the critical object is detected, namely in step S05. The method can then return to pure monitoring according to step S02, namely by deactivating the first alarm S06.However, if a critical change in the object's position is detected in step S07, whether by approaching the warning sign unit or even by crossing the boundary of the restricted area, a second alarm is activated in step S08, for example, through amplified visual and acoustic signals. Furthermore, a signal is sent to the control center, preferably accompanied by an identifier for the warning sign unit and one or more images of the detected object.

[0057] Figure 10 is a flowchart of a method for image recognition. In step S01, an image is captured by a camera. In step S02, the corresponding image data or previously processed image data is transferred to a neural network. In step S03, this data is then processed using neural network algorithms based on an image database of critical objects. For example, if one is only interested in recognizing people, the image database will contain images of people in a wide variety of positions and environments. In step S04, a check is then carried out to determine whether the image data of the captured image correspond to the image data of the critical objects from the image database. In this process, a reliability is always determined, whereby this determined reliability should lie above a predetermined reliability threshold. If this is the case, it is determined according to step S05 that a critical object has been detected.Otherwise, in step S06 it is determined that no critical object was detected.

[0058] The structure of the display device 100 according to the invention is explained using the following drawing figures using a manufacturing method for the display device 100.

[0059] Figure 11 shows a perspective view of a lattice frame 102 and components to be connected thereto.

[0060] In addition to the grid frame 102, a film 106 is shown, and at a schematic distance from this film 106, a grid image 110 is shown, with which the film 106 is back-printed. The film can be a polyester film with the specification "Autotex V200" and a thickness of 0.4 mm. This is resistant to ultraviolet radiation and also to numerous chemical influences. The grid image 110 printed on the film is preferably black. The grid frame 102 is preferably made of black acrylic glass with a thickness of 4 mm. The grid frame 102 and the back-printed film 108 are joined together at the edges with a double-sided adhesive tape 108.

[0061] Figure 12 shows a perspective section through the stack of film 106 and grid frame 102. The grid representation 110 can be seen on film 106. The grid openings of this grid representation 110 are smaller than the grid openings provided by the grid frame 102. For example, the grid openings of the grid representation have a size of 5 mm x 5 mm, while the grid frame has grid openings with a size of 7 mm x 7 mm.

[0062] Figure 13 shows an oblique top view of a grid frame 102. The regular arrangement of the grid openings 126 and the octagonal shape of the grid frame are visible here. Additionally, an opening 124 for an ambient light sensor is shown. This ambient light sensor can be a photodiode for controlling the brightness of the display depending on the ambient light intensity. Figure 14 is a perspective view of an LED circuit board 104 and components to be connected to it. These components are the grid frame 102 provided with the film, wherein the stack of film and grid frame 102 is enclosed by a mounting frame 128. The assembly of film, grid frame 102, LED circuit board, and mounting frame 128 is encapsulated with a potting compound 130. The potting compound 130 is transparent and contains a diffuser component. The mounting frame 128 prevents the potting compound 130 from flowing away.The mounting frame 128 is removed after the potting compound 130 has hardened.

[0063] Figure 15 shows an oblique top view of an LED circuit board 104. The LED circuit board 104 consists of four LED sub-circuit boards 104a, 104b, 104c, 104d, with one of the sub-circuit boards, here sub-circuit board 104a, acting as the master sub-circuit board. The remaining sub-circuit boards 104b, 104c, 104d are slave sub-circuit boards. The sub-circuit boards 104a, 104b, 104c, 104d are each equipped with 406 RGB LEDs, each with a color depth of 24 bits. A backup function is provided for the RGB LEDs, which ensures that the affected LED is bypassed in the event of an LED failure. This has the advantage that only one data line is required on the circuit board. Furthermore, the master sub-circuit board 104a contains a protection circuit, a temperature sensor and an ambient light sensor, preferably a photodiode, for brightness control or brightness regulation.The four sub-circuit boards 104a, 104b, 104c, 104d are mechanically and stably soldered to the circuit board 104 via the electrical connections already present.

[0064] Figure 16 shows an oblique top view of a potted system comprising foil, grid frame, LED circuit board 104, and mounting frame 128. The grid frame and foil are not visible here, as they are concealed by the mounting frame 128 and the circuit board 104. Also shown is a cable 130 soldered to the circuit board 104, with its soldered strands encased in the soldering area by the potting compound. Three set screws 132 are provided for each LED sub-circuit board; these are identified by reference numerals only for sub-circuit board 104a in the present illustration. These set screws 132 serve to align the circuit board 104 and grid frame 102 relative to each other before potting or before the potting compound hardens. Figure 17 shows a perspective view of the removal of the LED package 118 from the mounting frame 128. The arrangement of film, grid frame and circuit board is referred to below as LED package 118.

[0065] Figure 18 shows a perspective view of the LED package 118 and a housing pot 112. The LED package 118 is inserted into the housing pot 112 with its circuit board side 134 facing the housing pot base 114. Spacers (not shown) ensure that a sufficient distance remains between the housing pot base 114 and the LED package 118. These spacers can be fixed or adjustable. When the LED package 118 is in the housing pot 112, a gap remains between the housing pot wall 116 and the edge of the LED package 118. Potting compound 136 can then be poured over this edge.

[0066] Figure 19 shows a top view of the display device 100. Starting with the assembly shown in Figure 18, the display device is almost complete. It then only needs to be equipped with a two-part edge protector 136, 138. The edge protector 136, 138 is preferably made of plastic with a Shore A hardness between 65 and 85. The grid structure, which is visible in the top view, has been omitted from the illustration in Figure 19.

[0067] Figure 20 shows a perspective view of the display device 100. Here, the grid representation 110, which is printed from behind on the film facing the viewer, can be seen.

[0068] Figure 21 shows a plan view of the rear side of the display device 100. The housing base 114, enclosed by the edge protection 136, 138, is visible. Two fastening devices 120, 122 are provided on the housing base 114, with which the display device 100 can be suspended. One of the fastening devices 122 also shows a connecting piece for the electrical supply and data cable.

[0069] Figure 22 shows a perspective view of the display device. The same features can be seen as in Figure 21.

[0070] Figure 23 shows various side and sectional views of the display device 100.

[0071] Referring to Figure 21, Figure 23a shows a side view from the left. Referring to Figure 21, Figure 23b shows a side view from the right. Referring to Figure 21, Figure 23c shows a side view from above. Referring to Figure 21, Figure 23d shows a side view from below. Referring to Figure 21, Figure 23e shows a side view from the left, cut along line AA in Figure 21. Referring to Figure 21, Figure 23f shows a side view from below, cut along line BB in Figure 21.

[0072] Figure 24 shows a combination of a sign unit 10 and the display device 100. The sign unit 10 described in connection with Figures 1 to 10 serves as a support for the display device 100. The sign unit 10 is further equipped with lateral poles 140 for holding banners. These poles are designed like electric fence poles. For stability, the poles 140 are secured across the top of the sign unit 10 with a strap 142 or several straps, the overall length of which can be adjusted, for example, using hook-and-loop fasteners.

[0073] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential for the realization of the invention both individually and in any combination.

[0074] List of reference symbols

[0075] 10 information sign unit

[0076] 12 Border

[0077] 14 Restricted area

[0078] 16 Motion sensor

[0079] 18 objects

[0080] 20 Optical signaling device

[0081] 22 Acoustic signaling device

[0082] 24 central unit

[0083] 26 users

[0084] 28 Communication unit

[0085] 30 hearing protection

[0086] 32 mobile phone

[0087] 34 Detection module

[0088] 36 Camera

[0089] 38 GPS antenna

[0090] 40 tripod, support

[0091] 42 pipe

[0092] 44 Information sign

[0093] 46 Information banners

[0094] 48 cavity

[0095] 50 column

[0096] 52 LEDs

[0097] 54 heat sinks

[0098] 56 Controller unit

[0099] 58 mechanical interface

[0100] 62 electrical interface

[0101] 64 feet

[0102] 66 Anchoring device

[0103] 68 base plate

[0104] 70 Leg plate

[0105] 72 Recess Swivel axis Hole Slotted hole Rib O-ring

[0106] LED driver module

[0107] LIDAR module

[0108] LED, white

[0109] LED, orange

[0110] LED, red

[0111] LED, infrared

[0112] Laminating area

[0113] Display device

[0114] Lattice frame

[0115] circuit board

[0116] film

[0117] tape

[0118] Grid display

[0119] Housing pot

[0120] Housing pot base

[0121] Housing wall LED package

[0122] Fastening device

[0123] Fastening device

[0124] Opening for ambient light sensor Grille openings Mounting frame Cable

[0125] grub screw

[0126] PCB side edge protection edge protection

Claims

Claims 1. A planar display device (100) comprising a planar grid frame (102) and a planar LED circuit board (104), wherein the grid frame (102) and the circuit board (104) form a stack, wherein an arrangement of LEDs on the LED circuit board (104) is adapted to a grid structure of the grid frame (102), and wherein the LEDs on the LED circuit board (104) can be controlled individually and / or in groups, so that the display device (100) can provide different display images.

2. Planar display device (100) according to claim 1, characterized in that the stack additionally comprises a film (106), wherein the components of the stack are stacked in the order (i) film (106), (ii) grid frame (102), (iii) printed circuit board (104).

3. Flat display device (100) according to claim 2, characterized in that the film (106) and grid frame are connected at the edges with double-sided adhesive tape (108).

4. Planar display device (100) according to claim 2 or 3, characterized in that the film (106) is back-printed with a grid representation (110) whose grid constant corresponds to a grid constant of the grid frame (102).

5. Planar display device (100) according to claim 4, characterized in that grid openings of the grid frame (102) are larger than grid openings of the grid display (112).

6. A planar display device (100) according to any one of claims 2 to 5, characterized in that the film (106), the grid frame (102) and the circuit board (104) are encapsulated together, thereby forming an LED package (118).

7. Planar display device (100) according to one of the preceding claims, characterized in that the printed circuit board (104) is made up of several parts.

8. Planar display device (100) according to one of claims 2 to 7, characterized in that the stack additionally has a housing pot base (114) of a housing pot (112), wherein a housing pot wall (116) projects from the housing pot base (114), wherein the components of the stack are stacked in the order (i) film (106), (ii) grid frame (102), (iii) printed circuit board (104), (iv) housing pot base (114).

9. A planar display device (100) according to claim 8, characterized in that the LED package (118) and the housing pot are encapsulated together.

10. Planar display device (100) according to claim 8 or 9, characterized in that the housing pot (112) has at least one fastening device 120, 122 for the display device on its side facing away from the LED package (118).

11. Planar display device (100) according to one of the preceding claims, characterized in that an ambient light sensor is provided.

12. Planar display device (100) according to claim 11, characterized in that the ambient light sensor is arranged in an opening (124) of the grid plate.

13. Flat display device (100) according to one of the preceding claims, characterized in that the display device (100) can be coupled to an information sign unit (10) via an electrical interface, wherein electrical signals for determining the display images of the display device (100) are supplied from the information sign unit (10) to the display device (100) via the electrical interface.

Images