Abstract
The present disclosure relates to darkening filters 10, 10′ which are suitable for selectively darkening an optically transmissive window 20 for protection from light, in particular from high intensity light. The darkening filter 10, 10′ is mounted in a forward-facing optically transmissive window 20 and comprises a non-uniform pattern 30 of switchable shutters 32 capable of being switching to at least a dark state and a light state by a shutter control system 40. The present disclosure also relates to a method of operating such darkening filters 10, 10′. The present disclosure furthermore relates to vision-protective headgears 100, 100′, welding shields 110 and panes 120 comprising the darkening filters 10, 10′ according to the present disclosure.
Claims
1. A darkening filter mounted in a forward-facing optically transmissive window, the filter comprises a pattern of switchable shutters that are each capable of being switched between at least a dark state and a light state, and a shutter control system that is connected to each shutter of the pattern of shutters so as to be able to control the switching of each of the shutters, wherein the pattern of shutters is non-uniform.
2. The darkening filter of claim 1, further comprising at least one image acquisition device, wherein the shutter control system is receivably connected to the image acquisition device and wherein the shutter control system is configured to receive light intensity mapping information from the at least one image acquisition device, and is configured to use the light intensity mapping information to choose states to which the shutters are switched.
3. The darkening filter of claim 2, further comprising at least one eye position monitoring device, wherein the shutter control system is receivably connected to the eye position monitoring device and wherein the shutter control system is configured to receive light intensity mapping information and eye position information from the at least one eye position monitoring device, and is configured to use the received information in combination to choose states to which the shutters are switched.
4. The darkening filter according to claim 1, wherein the non-uniform pattern comprises shutters of different size and/or wherein the non-uniform pattern comprises shutters of different shape.
5. The darkening filter according to claim 1, wherein the non-uniform pattern is predetermined.
6. The darkening filter according to claim 1, wherein the non-uniform pattern is adjustable.
7. The darkening filter according to claim 1, wherein the non-uniform pattern comprises a first region having a first density of shutters per area and at least one second region having a second density of shutters per area and wherein the density of the shutters in the first region is higher than the density of the shutters in the second region.
8. The darkening filter according to claim 7, wherein the first region is arranged in a main view focus of the filter.
9. The darkening filter according to claim 7, wherein the filter comprises two first regions and wherein the two first regions are aligned with positions corresponding to the location of the eyes of a user.
10. The darkening filter according to claim 1, wherein the shutter control system is configured to use the light intensity mapping information and the eye position information in combination to identify a first set of shutters of the pattern of shutters as being positioned on a direct optical path between a source of light and at least a pupil of an eyeball of a user of the filter and wherein the shutter control system is configured to selectively switch the first set 42 of shutters from a light state to a dark state and to maintain them in the dark state.
11. The darkening filter according to claim 10, wherein the shutter control system is further configured to use the light intensity mapping information and the eye position information in combination to identify a second set of shutters of the pattern of shutters as not being positioned on a direct optical path between a source of light and at least a pupil of an eyeball of the user of the darkening.
12. The darkening filter according to claim 11, wherein the shutter control system is configured to maintain at least some shutters of the second set of shutters in a light state and/or to switch at least some shutters of the second set of shutters to an intermediate state and to maintain them in the intermediate state.
13. The darkening filter according to any of claim 1, wherein the first and second region(s) of first and second densities of shutters are arranged such that the first region is being positioned on a direct optical path between a source of light and at least a pupil of an eyeball of a user of the darkening filter; and such that the second region is not being positioned on a direct optical path between a source of light and at least a pupil of an eyeball of a user of the darkening filter.
14. Method of operating a darkening filter according to claim 1, the method comprising the steps of: using light intensity mapping information and eye position information in combination to identify a first set of shutters of the pattern of shutters, which first set of shutters is positioned on a direct optical path between a source of light and at least a pupil of an eyeball of a user of the filter; using the light intensity mapping information and eye position information in combination to identify a second set of shutters of the pattern of shutters, which second set of shutters is not positioned on a direct optical path between a source of light and at least a pupil of an eyeball of the user of the filter; and, selectively switching the first set of shutters from a light state to a dark state and maintaining them in the dark state, while maintaining at least some shutters of the second set of shutters in a light state.
15. A vision-protective headgear or a welding shield or a pane comprising a darkening filter according to claim 1, wherein the pane is part of a vehicle windscreen or a glazing of a building.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The disclosure will now be described in more detail with reference to the following Figures exemplifying particular embodiments of the disclosure:
[0033] FIG. 1 is a schematic view of a darkening filter according to one embodiment of the present disclosure with all shutters being in a light state;
[0034] FIG. 2 is a schematic view of the darkening filter of FIG. 1, with some shutters are in a dark state;
[0035] FIG. 3 is a schematic view of the darkening filter of FIG. 2, with in addition to shutters being in a dark state some shutters being in an intermediate state;
[0036] FIG. 4 is a schematic view of the darkening filter of FIG. 1 showing a light of high intensity;
[0037] FIG. 5 is a schematic view of the darkening filter of FIG. 4, with some shutters being in a dark state and some other shutters being in an intermediate state;
[0038] FIG. 6 is a schematic view of a darkening filter according to another embodiment of the present disclosure;
[0039] FIG. 7 is a schematic view of a darkening filter according to a further embodiment of the present disclosure;
[0040] FIG. 8 is a schematic view of a darkening filter and an image acquisition device according to one embodiment of the present disclosure and the eyes of a user;
[0041] FIG. 9 is a perspective view of a welding helmet having a darkening filter according to an embodiment of the present disclosure;
[0042] FIG. 10 is a perspective view of a welding helmet having a darkening filter according to an embodiment of the present disclosure;
[0043] FIG. 11 is a perspective view of a welding shield having a darkening filter according to an embodiment of the present disclosure, and
[0044] FIG. 12 is a top view of a pane having a darkening filter according to an embodiment of the present disclosure.
[0045] FIG. 13 shows in a schematic view a block diagram of one embodiment of a darkening filter according to the present disclosure.
DETAILED DESCRIPTION
[0046] A first embodiment of a darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, according to this disclosure is schematically shown in FIG. 1. The darkening filter 10 comprises a pattern 30 of switchable shutters 32. As illustrated, the pattern 30 is non-uniform, i.e. the size of the shutters 32 vary along two dimensions of the pattern 30. As can be seen from FIG. 1, shutters of rather large size are arranged in outer regions of the darkening filter 10, see e.g. in second region 36, whereas shutters with rather small size are arranged towards the center region of the darkening filter 10, see e.g. in the first region 34. Between the rather large shutters and the rather small shutters, the size of the shutters successively decreases. The switchable shutters 32 can be switched between a light state (as illustrated for the shutters 32 in FIG. 1) and a dark state (not illustrated in FIG. 1). The shutters 32 being in a light state exhibit a relatively high light transmissivity, whereas the shutters 32 being in a dark state are relatively non-transmissive to light. In some embodiments, the shutters 30 can also be switched to an intermediate state (not illustrated in FIG. 1). FIG. 1 furthermore shows a first region 34 having a first density of shutters and a second region 36 having a second density of shutters. As apparent from FIG. 1, the size of the shutters 32 in the first region 34 is less than the size of the shutters 32 in the second region 36. The size of the shutters 32 in the first region 34 is not necessarily the same for all shutters 32 of the first region 34, but it can vary even within the first region 34. Furthermore, size of the shutters 32 in the second region 36 is not necessarily the same for all shutters 32 of the first region 36, but it can vary even within the first region 36. In the embodiment shown, the position of the first region 34 is centered within the pattern 30. Alternatively, the position of the first region 34 can be different and/or more than one first regions 34 can be arranged. For example, two first regions 34 can be arranged (see FIG. 7). FIG. 2 shows the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, of the embodiment as shown in FIG. 1 with the pattern 30, where some shutters 32a of the pattern 30 have been switched to the dark state, shown as dark squares indicated by 42 in FIG. 2. The shutters 32a switched to the dark state are in or proximate to the first region 34 as indicated in FIG. 1, but not shown here. The shutters 32a may also be outside of the first region 34, e.g. they may belong to the second region 36, which is not indicated in FIG. 2. Some other shutters 32b of the pattern 30 are switched to the light state, shown as white squares as indicated by 44. The shutters 32b, which are switched to the light state, may be in or proximate the second region 36 as indicated in FIG. 1, but not shown here. The shutter 32b may also be outside of the second region 36, which is not indicated in FIG. 2. Although only a few shutters 32a of the pattern 30 are indicated in FIG. 2 as switched to the dark state, further of the shutters 32 may be switched to the dark state as well and simultaneously, respectively. As described above, in response to incident light (not shown here) to the darkening filter 10, the shutter control system (not shown) switches the shutters either to a dark state, an intermediate state or to a light state (or maintains the shutters in one of these states).
[0047] FIG. 3 shows the embodiment of the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, as shown in FIGS. 1 and 2. Here, in addition to the shutters 32a switched to the dark state and to shutters 32b switched to the light state, some shutters 32c are switched to an intermediate state, which are shown as grey squares as indicated with 46. The shutters 32c being in an intermediate state exhibit a light transmissivity in between of the light state and the dark state. As described above, in response to the incident light (not shown here) to the darkening filter 10, the shutter control system (not shown) switches the shutters either to a dark state, an intermediate state or to a light state (or maintains the shutters in one of these states).
[0048] FIG. 4 shows the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, as shown in FIG. 1 with the pattern 30 of switchable shutters 32. In addition, FIG. 4 shows an area of the darkening filter through which light from a light source 22 would be visible, indicated by 24. In the scenario as shown in FIG. 4, all shutters 32 are in a light state.
[0049] FIG. 5 shows the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, as shown in FIG. 4 including the area where light from a light source 22 (not shown here) would be visible, indicated by 24. In addition, FIG. 5 indicates that some shutters 32a of the pattern 30 are switched to a dark state, some shutters 32c are switched to an intermediate state, while some shutters 32b are not switched, i.e. remain in a light state. This is in response to the light impacting on the darkening filter 10 being emitted from the light source, not shown in FIG. 5. As can be seen from FIG. 5, the center of the area covered by the switched shutters 32a, 32c is covered by shutters 32a switched to a dark state, whereas the shutters 32c surrounding the shutters 32a switched to a dark state are switched to an intermediate state. As described above, in response to the incident light to the darkening filter 10, the shutter control system (not shown) switches the shutters 32a, 32b, 32c either to a dark state, an intermediate state or to a light state (or maintains the shutters in one of these states).
[0050] FIG. 6 shown an embodiment of the darkening filer 10, which is mounted in a forward-facing optically transmissive window 20, being different to the embodiment as shown in FIG. 1. Here, the first region 34 having a first density of shutters 32 is shifted from the center of the pattern 30 as shown in FIG. 1 to the left side. In addition, FIG. 6 shows a user or wearer 76 of the darkening filter. The first region 34 is aligned with the position of a user or wearer 76 and thus corresponds to the location of the eyes (not shown here) of the user or wearer 76.
[0051] FIG. 7 shows an embodiment of the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, with a pattern 30 of shutters 32 having two first regions 34a, 34b. The two first regions are each shifted to the left and to the right side, respectively, compared to the first region 34 as shown in FIG. 1. The two first regions 34a, 34b thereby form a left first region 34a and a right first region 34b. The two first regions 34a, 34b are aligned with positions corresponding to the location of the eyes of a user or wearer 76, both not shown in FIG. 7.
[0052] FIG. 8 shows the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, with the pattern 30 of switchable shutters 32 as shown in FIG. 4, where a light source 22 is shown which emits light resulting in light visible on the darkening filter 10 as indicated by 24. In addition, FIG. 8 shows two optical detectors 74a, 74b, e.g. cameras 74a, 74b. The cameras 74a, 74b are arranged such that one camera 74a is located on the left side of the darkening filter 10 and one camera 74b is located on the right side of the darkening filter 10. FIG. 8 furthermore shows the eyes 72a, 72b of a user or wearer 76, whereby the user or wearer 76 as such is not shown here. The cameras 74a, 74b are part of an image acquisition device, which is not shown in FIG. 8. The image acquisition device receives light from a light source 22 and compiles light intensity mapping information based on the received light. The shutter control system (not shown here) is receivable connected to the image acquisition device and receives the light intensity mapping information from there. Based on the light intensity mapping information, the shutter control system chooses the shutters 32 and the state to which these shutters 32 are switched, e.g. dark state, light state or intermediate state. The shutter control system may based on the received light intensity mapping information maintain some of the shutters 32 in a state where these have been in before. In the embodiment shown in FIG. 8, the shutters surrounding the area as indicated by 24 would be switched to a dark state in response to the light emitted from the light source 22.
[0053] FIG. 9 shows in a front-side perspective view of a vision-protective headgear 100 comprising the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, according to the present disclosure. In this embodiment, the darkening filter 10 is mounted in an opening in the headgear body. As can be seen from FIG. 9, the darkening filter 10 is flat. Alternatively, the darkening filter 10 may be curved, see FIG. 10 for more details. The headgear 100 may include a crown member (not shown) that engages the user's or wearer's head when the headgear is being donned.
[0054] FIG. 10 shows in a front-side perspective view a welding helmet 100′ comprising the darkening filter 10′, which is mounted in a forward-facing optically transmissive window 20, according to the present disclosure. In this embodiment, the darkening filter (10) is mounted in an opening in the welding helmet (100′). As can be seen in FIG. 10, the darkening filter 10′ is curved. Typically, a welding helmet 100′ comprises a main body and a suspension having a band for fixing the headgear. The darkening filter according to the present disclosure is typically mounted in a forward side of the headgear, i.e. in the direction of which the user or wearer is gazing into.
[0055] FIG. 11 shows in a front-side perspective view a welding shield 110 comprising the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, according to the present disclosure. In this embodiment, the darkening filter 10 is mounted in an opening in the welding shield body. As can be seen from FIG. 11, the darkening filter 10 is flat. Alternatively, the darkening filter 10 may be curved, see FIG. 10 for more details.
[0056] FIG. 12 shows in a top view a pane 120 comprising the darkening filter 10, which is mounted in a forward-facing optically transmissive window 20, according to the present disclosure. In this embodiment, the darkening filter 10 is mounted in an opening in the welding shield body. As can be seen from FIG. 11, the darkening filter 10 is flat. Alternatively, the darkening filter 10 may be curved, see FIG. 10 for more details. The pane 120 may be part of a vehicle windscreen or a glazing of a building (both not shown in FIG. 12).
[0057] FIG. 13 shows a block diagram of the darkening filter 10 according to one embodiment of the present disclosure. As can be seen, darkening filter 10 is mounted in a forward-facing optically transmissive window 20 and comprises a pattern 30 of switchable shutters 32, which can be switched between a dark state, a light state and one or more intermediate states. The darkening filter 10 further comprises a shutter control system 40, which is connected to each shutter 32 of the pattern 30 so as to be able to control the switching of each of the shutters 32. As can be seen, the pattern 30 is non-uniform. In the embodiment of FIG. 13, the darkening filter 10 moreover comprises an image acquisition device 50, wherein the shutter control system 40 is receivably connected to the image acquisition device 50. The shutter control system 40 is configured to receive light intensity mapping information from the image acquisition device 50 and is configured to use the light intensity mapping information to choose states to which the shutters 32 are switched. In the embodiment shown here, the darkening filter 10 moreover comprises an eye position monitoring device 60, wherein the shutter control system 40 is receivably connected to the eye position monitoring device 60. The shutter control system 40 is configured to receive light intensity mapping information from the image acquisition device 50 and eye position information from the eye position monitoring device 60 and is configured to use the received information in combination to choose states to which the shutters 32 are switched.
