Security System Having A Transparent Pane Device

Abstract

The invention relates to a security system (1) having a transparent pane device (2). The transparent pane device (2) is designed, for example, as a window of a room of a building or as a window of a transportation means. The security system (1) has a liquid crystal film (3) with an adjustable transparency, wherein the liquid crystal film (3) is arranged on the transparent pane device (2) and/or at a distance to the transparent pane device (2). A sensor unit (4, 5, 7A to 7E) is designed to emit a sensor signal. The sensor unit (4, 5, 7A to 7E) is arranged on the transparent pane device (2). In addition, a control device (8) is provided for adjusting the transparency of the liquid crystal film (3) in accordance with the sensor signal.

Claims

1. A safety system (1), having at least one transparent pane device (2, 20, 25), wherein the transparent pane device (2, 20) is embodied to be bullet-proof, impact-resistant and/or resistant to explosion effects, at least one liquid-crystal film (3) having a settable transparency, wherein the liquid-crystal film (3) is arranged at the transparent pane device (2, 20, 25) and/or at a distance from the transparent pane device (2, 20, 25), wherein light rays that are incident on the transparent pane device (2, 20, 25) transmit through the transparent pane device (2, 20, 25) and through the liquid-crystal film (3), at least one sensor unit (4, 5, 7A to 7E) for emitting a sensor signal, wherein the sensor unit (4, 5, 7A to 7E) is arranged at the transparent pane device (2, 20), and having at least one control device (8) for setting the transparency of the liquid-crystal film (4) in dependence on the sensor signal.

2. The safety system (1) as claimed in claim 1, wherein the sensor unit (4, 5, 7A to 7E) comprises at least on electrical conductor loop.

3. The safety system (1) as claimed in claim 1, wherein the sensor unit (4, 5, 7A to 7E) comprises at least one light sensor.

4. The safety system (1) as claimed in claim 3, wherein the light sensor (7A to 7E) is embodied as a CCD sensor, as a photodiode, as a phototransistor or as a photoresistor.

5. The safety system (1) as claimed in claim 1, claims, wherein the sensor unit (4, 5, 7A to 7E) comprises at least one shock sensor (5).

6. The safety system (1) as claimed in claim 5, wherein the shock sensor (5) is embodied as an acceleration sensor.

7. The safety system (1) as claimed in claim 1, wherein the safety system (1) has one of the following features: (i) the transparent pane device (2, 20, 25) is formed in part from glass; (ii) the transparent pane device (2, 20, 25) is formed entirely from glass; (iii) the transparent pane device (2, 20, 25) is formed in part from plastics; (iv) the transparent pane device (2, 20, 25) is formed entirely from plastics.

8. The safety system (1) as claimed in claim 1, wherein the transparent pane device (20, 25) includes a laminated safety glass, which comprises a first glass pane (21, 26) and a second glass pane (22, 27), wherein at least one film unit (24) made of polyvinyl butyral and/or ionoplast is arranged between the first glass pane (21, 26) and the second glass pane (22, 27).

9. The safety system (1) as claimed in claim 8, wherein the film unit (24) has between the first glass pane (21, 26) and the second glass pane (22, 27) at least one intermediate layer of the trademark SENTRYGLAS.

10. The safety system (1) as claimed in claim 1, wherein the transparent pane device (20, 25) includes a laminated safety glass device (25), the laminated safety glass device (20) comprises at least one first glass pane (21), at least one second glass pane (22) and at least one third glass pane (28), arranged between the first glass pane (21) and the second glass pane (22) is at least one first film unit (29) made of polyvinyl butyral and/or ionoplast, and wherein arranged between the second glass pane (22) and the third glass pane (28) is at least one second film unit (30) made of polyvinyl butyral and/or ionoplast.

11. The safety system (1) as claimed in claim 10, wherein the first film unit (29) and/or the second film unit (30) has at least one intermediate layer of the trademark SENTRYGLAS.

12. The safety system (1) as claimed in claim 10 or 11, wherein the second film unit (30) has one of the following features: (i) the second film unit (30) comprises at least two films (31 to 34) which are arranged parallel with respect to one another; (ii) the second film unit (30) comprises at least four films (31 to 34) which are arranged parallel with respect to one another; (iii) the second film unit (30) comprises at least six films (31 to 34) which are arranged parallel with respect to one another.

13. The safety system (1) as claimed in claim 1, wherein the control device (8) has a first switch state and a second switch state, the sensor unit (4, 5, 7A to 7E) has at one switch output of the sensor unit (4, 5, 7A to 7E) a first sensor signal for the first switch state or a second sensor signal for the second switch state, and wherein the liquid-crystal film (3) in the second switch state is embodied to be non-see-through.

14. A safety system (1), having at least one transparent pane device (2, 20, 25), at least one liquid-crystal film (3) having a settable transparency, wherein the liquid-crystal film (3) is arranged at the transparent pane device (2, 20, 25) and/or at a distance from the transparent pane device (2, 20, 25), wherein light rays that are incident on the transparent pane device (2, 20, 25) transmit through the transparent pane device (2, 20, 25) and through the liquid-crystal film (3), at least one sensor unit (4, 5, 7A to 7E) for emitting a sensor signal, wherein the sensor unit (4, 5, 7A to 7E) is arranged at the transparent pane device (2, 20), and having at least one control device (8) for setting the transparency of the liquid-crystal film (3) in dependence on the sensor signal.

15. A method for securing a space (200) using a safety system (1) as claimed in claim 1, wherein the method has the following steps: detecting a property by the sensor unit (4, 5, 7A to 7E); producing a sensor signal; passing the sensor signal to the control device (8); and setting the transparency of the liquid-crystal film (3) by way of the control device (8) in dependence on the sensor signal.

16. The method as claimed in claim 15, wherein the transparency is set such that the liquid-crystal film (3) is non-see-through.

17. A method for securing a space (200) using a safety system (1) as claimed in claim 14, wherein the method has the following steps: detecting a property by the sensor unit (4, 5, 7A to 7E); producing a sensor signal; passing the sensor signal to the control device (8); and setting the transparency of the liquid-crystal film (3) by way of the control device (8) in dependence on the sensor signal.

18. The method as claimed in claim 17, wherein the transparency is set such that the liquid-crystal film (3) is non-see-through.

Description

[0026] The invention will be explained in more detail below with reference to exemplary embodiments. In the figures

[0027] FIG. 1 shows a schematic illustration of a first embodiment of a safety system according to the invention;

[0028] FIG. 2 shows a schematic illustration of a second embodiment of a safety system according to the invention;

[0029] FIG. 3 shows a schematic illustration in the form of a sectional view of part of a third embodiment of a safety system according to the invention; and

[0030] FIG. 4 shows a schematic flowchart of an embodiment of the method according to the invention.

[0031] FIG. 1 shows a schematic illustration of a first embodiment of the safety system 1 according to the invention, which separates an exterior region 100 from an interior space 200. The interior space 200, for example, is a space of a building or of a transport means. The transport means is in particular embodied as a motor vehicle, as an aircraft or as a ship.

[0032] The safety system 1 has a transparent pane device 2, which is formed from glass, for example. In the exemplary embodiment illustrated in FIG. 1, the transparent pane device is embodied as a toughened safety glass. Alternatively or additionally, the transparent pane device 2 can also be made from plastics, for example from plexiglass.

[0033] The transparent pane device 2 can, in a further embodiment, be embodied to be bullet-proof, impact-resistant and/or resistant to explosion effects. To this end, the transparent pane device 2 has, for example, a thickness of a few centimeters, for example 3 cm to 30 cm. This thickness is attained, for example, by a plurality of glass panes being adhesively bonded together.

[0034] The transparent pane device 2 has two sides. A first side faces the exterior region 100. A second side of the transparent pane device 2 faces the interior space 200. Arranged on the second side is a liquid-crystal film 3. Also arranged on the second side is a sensor unit which has for example an electrical conductor loop 4 and/or a shock sensor 5. The electrical conductor loop 4 is connected to a control device 8 via a first connecting line 9. The shock sensor 5 is connected to the control device 8 via a second connecting line 10. Moreover, the liquid-crystal film 3 is connected to the control device 8 via a third connecting line 11. The control device 8 is provided to supply the liquid-crystal film 3 with a supply voltage, wherein the supply voltage is used for the alignment of the liquid crystals.

[0035] Applied on the first side of the transparent pane device 2 is a film 6 made of polyvinyl butyral (PVB), in which, additionally or alternatively to the already above-mentioned sensors, light sensors 7A to 7E are arranged, specifically a first light sensor 7A, a second light sensor 7B, a third light sensor 7C, a fourth light sensor 7D and a fifth light sensor 7E.

[0036] The liquid-crystal film 3 in the embodiment of the safety system 1 illustrated here is arranged directly on the transparent pane device 2. In further embodiments, a further film unit is arranged between the transparent pane device 2 and the liquid-crystal film 3, for example a film unit made from PVB. This will be explained in more detail further below.

[0037] Light rays that are incident on the transparent pane device 2 transmit through the transparent pane device 2 and through the liquid-crystal film 3. In other words, first arranged in a light incidence direction E is the transparent pane device 2 and then the liquid-crystal film 3.

[0038] The liquid-crystal film 3 exhibits a settable transparency. For example, the liquid-crystal film 3 can adopt a first transparency state and a second transparency state. In the first transparency state, the liquid-crystal film 3 is, for example, transparent or nearly transparent. In the second transparency state, the liquid-crystal film 3 is, for example, non-see-through. The transparency states are actuated via the control device 8. By applying a voltage to the liquid-crystal film 3, poles of liquid crystals of the liquid-crystal film 3 align such that the liquid-crystal film 3 becomes transparent and thus adopts the first transparency state. If no voltage is applied, the liquid crystals have a random orientation. Light that is incident in the liquid-crystal film 3 is therefore strongly diffused. The liquid-crystal film 3 then becomes opaque. It is consequently non-see-through, that is to say not transparent. This is the second transparency state.

[0039] The electrical conductor loop 4 is formed as a thin wire. It has the shape of a spider's web. Current flows through the electrical conductor loop 4. If the transparent pane device is destroyed by way of the impact of a force on the transparent pane device 2 (for example by arms fire and/or due to shrapnel from an explosion), the electrical conductor loop 4 is destroyed and the circuit is interrupted. The interruption of the circuit is detected by the control device 8 via the first connecting line 9. The control device 8 then actuates the liquid-crystal film 3 in a manner such that the liquid-crystal film 3 becomes non-see-through. Consequently, the voltage that has been applied to the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0040] As already mentioned, provision is additionally or alternatively made for a shock sensor 5 to be arranged at the safety system 1. The shock sensor 5 is embodied for example as an acceleration sensor. Upon the impact of force on the transparent pane device 2, for example due to being shot at with a bullet and/or due to shrapnel from an explosion, the shock sensor 5 detects said impact and produces a corresponding sensor signal, which it passes on to the control device 8 via the second connecting line 10. The control device 8 in turn controls the liquid-crystal film 3 in a manner such that the liquid-crystal film 3 becomes non-see-through. Accordingly, the voltage for supplying the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0041] The light sensors 7A to 7E are embodied for example as a CCD sensor, a photodiode, a phototransistor or a photoresistor. If target acquisition and/or a distance measurement by way of a light beam, in particular a laser beam, is/are underway, this is ascertained using at least one of the light sensors 7A to 7E. As soon as such a light beam is detected by at least one of the light sensors 7A to 7E, a sensor signal is produced by at least one of the light sensors 7A to 7E and passed to the control device 8 via a connecting line, which is not illustrated in FIG. 1. The control device 8 immediately actuates the liquid-crystal film 3 such that it becomes non-see-through. Accordingly, the supply voltage to the liquid-crystal film 3 is switched off. Provision is additionally made even here for the alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0042] Switching the liquid-crystal film 3 to a non-see-through state takes place for example even if for example a failure in the general supply of the liquid-crystal film 3 with voltage is detected at the control device 8. Consequently, for example in the case of a general power failure, the liquid-crystal film 3 is switched to a safety mode, specifically the second transparency state in which the liquid-crystal film 3 is non-see-through.

[0043] In an embodiment of the safety system 1, provision is additionally or alternatively made for the transparency of the liquid-crystal film 3 to be able to be brought into a desired state, for example the above-mentioned first transparency state or the above-mentioned second transparency state, by way of operating the control device 8. In other words, the control device 8 has an input device with which a desired transparency state of the liquid-crystal film 3 is settable. This is advantageous in particular if a user wishes not to be disturbed and/or intends to block the view into a space from the start.

[0044] FIG. 2 shows a schematic illustration of a second embodiment of the safety system 1 according to the invention. The safety system 1 according to FIG. 2 separates an exterior region 100 from an interior space 200. The interior space 200, for example, is a space of a building or of a transport means. The transport means is in particular embodied as a motor vehicle, as an aircraft or as a ship.

[0045] The safety system 1 has a first laminated safety glass device 20, which has a first glass pane 21 and a second glass pane 22. The first glass pane 21 and the second glass pane 22 are formed from glass. Alternatively or additionally, the first glass pane 21 and/or the second glass pane 22 can be made from plastics, for example from plexiglass. Arranged between the first glass pane 21 and the second glass pane 22 is a film unit 24. The film unit 24 is made, for example, from PVB and/or ionoplast. However, reference is explicitly made to the fact that the invention is not limited to these types of film unit 24. Rather, the invention allows the use of any film unit that is suitable for the invention. For example, the film unit 24 can also be made of ethylene vinyl acetate.

[0046] In a further form of the exemplary embodiment of FIG. 2, provision is additionally or alternatively made for the film unit 24 to be embodied as a film of a thermoplastic, for example in the form of an ionoplast, between the first glass pane 21 and the second glass pane 22, wherein the film is sold, for example, under the trademark SENTRYGLAS by the company DuPont. This film is considerably stronger and stiffer than other films (for example those made of polyvinyl butyral or ethylene vinyl acetate). Using this film therefore allows the use of such glass panes for the laminated safety glass device 20 that are thinner and consequently also more lightweight as compared to other exemplary embodiments, but which nevertheless render the laminated safety glass device 20 sufficiently bullet-proof, impact-resistant and/or resistant to explosion effects.

[0047] Arranged on the film unit 24 is a sensor unit for example in the form of an electrical conductor loop 4 and/or a shock sensor 5. The electrical conductor loop 4 is connected to a control device 8 via a first connecting line 9. The shock sensor 5 is connected to the control device 8 via a second connecting line 10.

[0048] The safety system 1 also has a second laminated safety glass device 25, which is separated from the first laminated safety glass device 20 by an intermediate space 23 by being arranged at a distance therefrom. The intermediate space 23 is defined by at least one spacer 37. The intermediate space 23 can be filled, for example, with a gas for thermal insulation. The second laminated safety glass device 25 has a first glass element 26 and a second glass element 27. Both the first glass element 26 and the second glass element 27 are embodied in the form of a toughened safety glass. Alternatively or additionally, the first glass element 26 and/or the second glass element 27 can be made from plastics, for example plexiglass.

[0049] Arranged between the first glass element 26 and the second glass element 27 is a liquid-crystal film 3. The liquid-crystal film 3 in the embodiment of the safety system 1 illustrated here is arranged both directly on the first glass element 26 and directly on the second glass element 27. In other embodiments, a first film unit is arranged between the first glass element 26 and the liquid-crystal film 3. In this other embodiment, a second film unit is additionally arranged between the second glass element 27 and the liquid-crystal film 3. The first film unit and/or the second film unit is/are formed, for example, from PVB. The liquid-crystal film 3 is connected to the control device 8 via a third connecting line 11. The control device 8 is provided for supplying the liquid-crystal film 3 with a supply voltage, wherein the supply voltage is used for the alignment of the liquid crystals.

[0050] Light rays that are incident on the first laminated safety glass device 20 transmit through the first laminated safety glass device 20 and through the liquid-crystal film 3. In other words, first arranged in a light incidence direction E is the first laminated safety glass device 20 and then the second laminated safety glass device 25 with the liquid-crystal film 3.

[0051] The liquid-crystal film 3 also has a settable transparency in the embodiment of the safety system 1 that is illustrated in FIG. 2. By way of example, the liquid-crystal film 3 can adopt a first transparency state and a second transparency state. In the first transparency state, the liquid-crystal film 3 is, for example, transparent or nearly transparent. In the second transparency state, the liquid-crystal film 3 is, for example, non-see-through.

[0052] In the embodiment of the safety system 1 according to the invention that is illustrated in FIG. 2, the transparency states are also actuated via the control device 8. By applying a voltage to the liquid-crystal film 3, poles of liquid crystals of the liquid-crystal film 3 align such that the liquid-crystal film 3 becomes transparent and thus adopts the first transparency state. If no voltage is applied, the liquid crystals have a random orientation. Light that is incident in the liquid-crystal film 3 is therefore strongly diffused. The liquid-crystal film 3 then becomes opaque. Accordingly, it is non-see-through, that is to say non-transparent. This is the second transparency state.

[0053] In the embodiment of the safety system 1 according to the invention that is illustrated in FIG. 2, the electrical conductor loop 4 is also embodied as a thin wire. It has the shape of a spider's web. Current flows through the electrical conductor loop 4. If the first glass pane 21 and/or the second glass pane 22 of the first laminated safety glass device 20 is/are destroyed by the impact of a force on the first laminated safety glass device 20 (for example on the first glass pane 21) (for example due to bullets and/or shrapnel from an explosion), the electrical conductor loop is destroyed and the circuit is interrupted. The interruption of the circuit is detected by the control device 8 via the first connecting line 9. The control device 8 actuates the liquid-crystal film 3 such that the liquid-crystal film 3 becomes non-see-through. Accordingly, the voltage that has been applied to the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0054] As mentioned above, the embodiment of FIG. 2 can additionally or alternatively have the shock sensor 5. The shock sensor 5 is embodied for example as an acceleration sensor. If force acts on the first laminated safety glass device 20, in particular on the first glass pane 21 (for example due to being shot at with a bullet and/or due to shrapnel from an explosion), the shock sensor 5 detects this impact and produces a corresponding sensor signal, which it passes on to the control device 8 via the second connecting line 10. The control device 8 in turn actuates the liquid-crystal film 3 such that the liquid-crystal film 3 becomes non-see-through. Accordingly, the voltage for supplying the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0055] Switching the liquid-crystal film 3 to a non-see-through state also takes place if, for example, a failure in the general supply of the liquid-crystal film 3 with voltage is detected at the control device 8. Consequently, for example in the case of a general power failure, the liquid-crystal film 3 is switched to a safety mode, specifically the second transparency state in which the liquid-crystal film 3 is non-see-through. In another embodiment of the safety system 1, provision is additionally or alternatively made for the transparency of the liquid-crystal film 3 to be able to be brought into a desired state, for example the above-mentioned first transparency state or the above-mentioned second transparency state, by way of operating the control device 8. In other words, the control device 8 has an input device with which a desired transparency state of the liquid-crystal film 3 is settable. This is advantageous in particular if a user wishes not to be disturbed and/or intends to block the view into a space from the start.

[0056] FIG. 3 shows a schematic illustration in the form of a sectional view of part of a third embodiment of the safety system 1 according to the invention. The safety system 1 according to FIG. 3 separates an exterior region 100 from an interior space 200. The interior space 200, for example, is a space of a building or of a transport means. The transport means is in particular embodied as a motor vehicle, as an aircraft or as a ship.

[0057] The safety system 1 has a first laminated safety glass device 20, which has a first glass pane 21, a second glass pane 22 and a third glass pane 28. The first glass pane 21, the second glass pane 22 and the third glass pane 28 are formed from glass. Alternatively or additionally, the first glass pane 21, the second glass pane 22 and/or the third glass pane 28 can be made from plastics, for example from plexiglass.

[0058] Arranged between the first glass pane 21 and the second glass pane 22 is a first film unit 29. The first film unit 29 is made, for example, from PVB and/or ionoplast. However, reference is explicitly made to the fact that the invention is not limited to this type of first film unit 29. Rather, the invention allows the use of any film unit that is suitable for the invention. For example, the first film unit 29 can also be made of ethylene vinyl acetate.

[0059] Arranged between the second glass pane 22 and the third glass pane 28 is a second film unit 30. The second film unit 30 has four films in total, specifically a first film 31, a second film 32, a third film 33 and a fourth film 34. At least one of the films 31 to 34 is made from PVB and/or ionoplast. Reference is again explicitly made to the fact that the invention is not limited to this type of films 31 to 34. Rather, the invention allows the use of any films 31 to 34 that are suitable for the invention. For example, the films 31 to 34 can also be made of ethylene vinyl acetate.

[0060] The first glass pane 21 and the second glass pane 22 can be formed for example from toughened safety glass. The third glass pane 28 can be made from float glass, for example.

[0061] In a further form of the exemplary embodiment of FIG. 3, provision is additionally or alternatively made for the first film unit 29 and/or the second film unit 30 (more specifically at least one or all of films 31 to 34) to be embodied as a thermoplastic, for example in the form of an ionoplast, wherein the first film unit 29 and/or the second film unit 30 (i.e. films 31 to 34) is/are sold, for example, under the trademark SENTRYGLAS by the company DuPont. Such film units are considerably stronger and stiffer than other films (for example those made of polyvinyl butyral or ethylene vinyl acetate). Using such film units therefore allows the use of such glass panes for the laminated safety glass device 20 that are thinner and consequently also more lightweight as compared to other exemplary embodiments, but which nevertheless render the laminated safety glass device 20 sufficiently bullet-proof, impact-resistant and/or resistant to explosion effects.

[0062] Arranged on the first film unit 29 is a sensor unit for example in the form of an electrical conductor loop 4 and/or a shock sensor 5. The electrical conductor loop 4 is connected to a control device 8 via a first connecting line 9. The shock sensor 5 is connected to the control device 8 via a second connecting line 10.

[0063] The safety system 1 also has a second laminated safety glass device 25, which is separated from the first laminated safety glass device 20 by an intermediate space 23 by being arranged at a distance therefrom. The intermediate space 23 is defined by at least one spacer and separates the third glass pane 28 of the first laminated safety glass device 20 from a first glass element 26 of the second laminated safety glass device 25. The intermediate space 23 is filled, for example, with a gas for thermal insulation. The second laminated safety glass device 25 moreover has a second glass element 27. Both the first glass element 26 and the second glass element 27 of the second laminated safety glass device 25 are embodied in the form of a toughened safety glass. Alternatively or additionally, the first glass element 26 and/or the second glass element 27 can be made from plastics, for example plexiglass.

[0064] Arranged between the first glass element 26 and the second glass element 27 is a liquid-crystal film 3. To be precise, a first film element 35 is additionally arranged between the first glass element 26 and the liquid-crystal film 3. A second film element 36 is additionally arranged between the second glass element 27 and the liquid-crystal film 3. The first film element 35 and/or the second film element 36 is/are formed, for example, from PVB. The liquid-crystal film 3 is connected to the control device 8 via a third connecting line 11. The control device 8 is provided for supplying the liquid-crystal film 3 with a supply voltage, wherein the supply voltage is used for the alignment of the liquid crystals.

[0065] Light rays that are incident on the first laminated safety glass device 20 transmit through the first laminated safety glass device 20 and through the liquid-crystal film 3. In other words, first arranged in a light incidence direction E is the first laminated safety glass device 20 and then the second laminated safety glass device 25 with the liquid-crystal film 3.

[0066] The liquid-crystal film 3 also has a settable transparency in the embodiment of the safety system 1 that is illustrated in FIG. 3. By way of example, the liquid-crystal film 3 can adopt a first transparency state and a second transparency state. In the first transparency state, the liquid-crystal film 3 is, for example, transparent or nearly transparent. In the second transparency state, the liquid-crystal film 3 is, for example, non-see-through.

[0067] In the embodiment of the safety system 1 according to the invention that is illustrated in FIG. 3, the transparency states are also actuated via the control device 8. By applying a voltage to the liquid-crystal film 3, poles of liquid crystals of the liquid-crystal film 3 align such that the liquid-crystal film 3 becomes transparent and thus adopts the first transparency state. If no voltage is applied, the liquid crystals have a random orientation. Light that is incident in the liquid-crystal film 3 is therefore strongly diffused. The liquid-crystal film 3 then becomes opaque.

[0068] Accordingly, it is non-see-through, that is to say non-transparent. This is the second transparency state.

[0069] In the embodiment of the safety system 1 according to the invention that is illustrated in FIG. 3, the electrical conductor loop 4 is also embodied as a thin wire. It has the shape of a spider's web. Current flows through the electrical conductor loop 4. If the first glass pane 21 and/or the second glass pane 22 of the first laminated safety glass device 20 is/are destroyed by the impact of a force on the first laminated safety glass device 20 (for example on the first glass pane 21) (for example due to bullets and/or shrapnel from an explosion), the electrical conductor loop is destroyed and the circuit is interrupted. The interruption of the circuit is detected by the control device 8 via the first connecting line 9. The control device 8 actuates the liquid-crystal film 3 such that the liquid-crystal film 3 becomes non-see-through. Accordingly, the voltage that has been applied to the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0070] As mentioned above, in the embodiment of FIG. 3, provision is additionally or alternatively made for the shock sensor 5 to be used. The shock sensor 5 is embodied for example as an acceleration sensor. If force acts on the first laminated safety glass device 20, in particular on the first glass pane 21 (for example due to being shot at with a bullet and/or due to shrapnel from an explosion), the shock sensor 5 detects this impact and produces a corresponding sensor signal, which it passes on to the control device 8 via the second connecting line 10. The control device 8 in turn actuates the liquid-crystal film 3 such that the liquid-crystal film 3 becomes non-see-through. Accordingly, the voltage for supplying the liquid-crystal film 3 is switched off. Provision is additionally made in this embodiment for an alarm notification system (not illustrated), which is provided at the safety system 1, to be activated and for an alarm to be triggered.

[0071] In the exemplary embodiment according to FIG. 3, switching the liquid-crystal film 3 to a non-see-through state can also take place if, for example, a failure in the general supply of the liquid-crystal film 3 with voltage is detected at the control device 8. Consequently, for example in the case of a general power failure, the liquid-crystal film 3 is switched to a safety mode, specifically the second transparency state in which the liquid-crystal film 3 is non-see-through.

[0072] In another embodiment of the safety system 1, provision is additionally or alternatively made for the transparency of the liquid-crystal film 3 to be able to be brought into a desired state, for example the above-mentioned first transparency state or the above-mentioned second transparency state, by way of operating the control device 8. In other words, the control device 8 has an input device with which a desired transparency state of the liquid-crystal film 3 is settable. This is advantageous in particular if a user wishes not to be disturbed and/or intends to block the view into a space from the start.

[0073] FIG. 4 shows a flowchart of a method according to the invention. The method according to the invention makes provision in a method step S1 for a property to be detected by the sensor unit. Exemplary embodiments of the sensor unit have been discussed in detail further above. The detected property is for example a shock, a destruction of the transparent pane device 2, destruction of the glass panes 21, 22 and/or 28 of the first laminated glass safety device 20 and/or incidence of light on the transparent pane device 2 or the first laminated safety glass device 20 from a laser measuring device or a laser targeting device. If this property is detected, a sensor signal is produced in a method step S2. The sensor signal is passed to the control device in a method step S3. The control device 8 sets the transparency of the liquid-crystal film 3 in dependence on the sensor signal in a method step S4. In other words, the control device 8 sets the transparency state of the liquid-crystal film 3. Provision is made in particular for the transparency to be set such that the liquid-crystal film 3 becomes non-see-through.

[0074] All exemplary embodiments of the safety system 1 according to the invention have the advantage that, when danger or imminent danger is ascertained by one of the previously described sensor units, a sensor signal can be emitted to the control device 8 such that the control device 8 actuates the liquid-crystal film 3 such that the liquid-crystal film 3 becomes non-see-through. Consequently, the view through the liquid-crystal film 3 into a space located behind the liquid-crystal film 3 (for example the interior space 200) and/or the view of an object that is situated behind the liquid-crystal film 3 is blocked. Third parties are consequently unable to view the object or the interior space 200. As a consequence, the safety for example of persons situated in the interior space 200 is increased. The invention is suitable in particular for protecting persons and objects against arms fire or explosion effects, in particular effects of shrapnel.

[0075] The features of the invention disclosed in the present description, in the drawings and in the claims can be essential individually and in any desired combinations for implementing the invention in its various embodiments. The invention is not limited to the embodiments described. It can be varied within the scope of the claims and taking into account the knowledge of a person skilled in the art.

LIST OF REFERENCE SIGNS

[0076] 1 safety system

[0077] 2 transparent pane device

[0078] 3 liquid-crystal film

[0079] 4 electrical conductor loop

[0080] 5 shock sensor

[0081] 6 film

[0082] 7A first light sensor

[0083] 7B second light sensor

[0084] 7C third light sensor

[0085] 7D fourth light sensor

[0086] 7E fifth light sensor

[0087] 8 control device

[0088] 9 first connecting line

[0089] 10 second connecting line

[0090] 11 third connecting line

[0091] 20 first laminated safety glass device

[0092] 21 first glass pane

[0093] 22 second glass pane

[0094] 23 intermediate space

[0095] 24 film unit

[0096] 25 second laminated safety glass device

[0097] 26 first glass element

[0098] 27 second glass element

[0099] 28 third glass pane

[0100] 29 first film unit

[0101] 30 second film unit

[0102] 31 first film

[0103] 32 second film

[0104] 33 third film

[0105] 34 fourth film

[0106] 35 first film element

[0107] 36 second film element

[0108] 37 spacer

[0109] 100 exterior region

[0110] 200 interior space

[0111] E light incidence direction

[0112] S1 to S4 method steps