Abstract
A dome (102) for a monitoring camera system comprises several monitoring cameras. The dome is formed from a transparent material, and has a toroidal shape with a rotational symmetry along a rotational angle (α) around a first axis of symmetry (S1). An outer segment of the dome, in section, has a shape further defined by a second axis of symmetry (S2) arranged at a first radius (13) from the first axis of symmetry (S1) and is orthogonal to the first axis. The outer segment has a curvature following a second radius (r) over an angle (β) around the second axis of symmetry (S2).
Claims
1. A device comprising: a dome formed from a material to pass light at a wavelength interval, wherein the dome has rotational symmetry around a first axis over a first angle, wherein an outer segment of the dome has a shape defined by a second axis, wherein the second axis is orthogonal to the first axis, is curved, and is located at a first radius from the first axis, wherein the outer segment is curved and is located at a second radius from the second axis over a second angle, wherein the second radius is constant over the second angle, wherein the second angle extends about the second axis from a first line to a second line and beyond, wherein the first line extends outward from the first axis and intersects the first axis and the second axis, and wherein the second line is parallel to the first axis and intersects the second axis, and wherein the second radius is smaller than the first radius.
2. The device of claim 1, further comprising: a central segment extending between the first axis and the outer segment, wherein the central segment includes an undulated segment.
3. The device of claim 2, further comprising: a monitoring camera; and a base, wherein the monitoring camera is arranged on the base and is covered by the dome, and wherein the monitoring camera is configured to tilt about a tilt axis, wherein the tilt axis coincides with the second axis.
4. The device of claim 3, wherein the monitoring camera is configured to move between positions along the second axis.
5. The device of claim 2, wherein the central segment connects the outer segment with the first axis of symmetry, the central segment being arranged with an offset in relation to a plane defined by the curvature of the outer segment.
6. The device of claim 1, wherein the second angle is larger than 90°.
7. The device of claim 1, further comprising: a camera arranged on a base and covered by the dome, wherein the camera is configured to tilt about a tilt axis that coincides with the second axis, and wherein the second angle extends beyond the second line such that, when the camera is pointed in a direction straight along the second line, the second angle extends throughout a field of view of the camera.
8. The device of claim 7, wherein the second angle extends beyond the second line such that, when the camera is pointed in a direction away from the second line and toward the first axis, the second angle extends throughout a field of view of the camera.
9. A dome for a monitoring camera system comprising: several monitoring cameras; said dome being formed from material transparent to a wavelength interval relevant to the monitoring device, wherein the dome has a toroidal shape with a rotational symmetry along a rotational angle around a first axis of symmetry, wherein an outer segment of the dome, in section, has a shape further defined by a second axis of symmetry arranged at a first radius from the first axis of symmetry and being orthogonal to the first axis, wherein said outer segment has a curvature following a second radius over an angle around the second axis of symmetry, and wherein a central segment connects the outer segment with the first axis of symmetry, wherein the central segment is an undulated segment comprising one or more curvatures.
10. The dome of claim 9, wherein the dome is manufactured from a single material or a single material compound.
11. The dome of claim 9, wherein the rotational angle is less than 360°.
12. The dome of claim 9, wherein the second radius is smaller than the first radius.
13. The dome of claim 9, wherein the outer segment has an arcuate shape having an extension, wherein said extension exceeds 90°.
14. The dome for a monitoring camera system of claim 9, wherein a central segment connects the outer segment with the first axis of symmetry, the central segment being arranged with an offset in relation to a plane defined by the curvature of the outer segment.
15. A dome for a monitoring camera system comprising: several monitoring cameras; said dome being formed from a material transparent to a wavelength interval relevant to the monitoring device, wherein the dome has a toroidal shape with a rotational symmetry along a rotational angle around a first axis of symmetry, wherein an outer segment of the dome, in section, has a shape further defined by a second axis of symmetry arranged at a first radius from the first axis of symmetry and being orthogonal to the first axis, wherein said outer segment has a curvature following a second radius over an angle around the second axis of symmetry; and a central segment to connect the outer segment with the first axis of symmetry, wherein the central segment is an undulated segment, wherein the central segment forms a central dome configured for the arrangement of one of the monitoring cameras under the central dome.
16. The dome of claim 15, wherein the dome is manufactured from a single material or a single material compound.
17. The dome of claim 15, wherein the rotational angle is less than 360°.
18. The dome of claim 15, wherein the second radius is smaller than the first radius.
19. The dome of claim 15, wherein the outer segment has an arcuate shape having an extension, wherein the extension exceeds 90°.
20. A device comprising: a dome formed from a material to pass light at a wavelength interval, wherein the dome has rotational symmetry around a first axis along a first angle, wherein an outer segment of the dome has a shape defined by a second axis, wherein the second axis is orthogonal to the first axis, is curved, and is located at a first radius from the first axis, wherein the outer segment is curved and is located at a second radius from the second axis over a second angle, wherein the second angle extends about the second axis from a first line to a second line and beyond, wherein the first line extends outward from the first axis and intersects the first axis and the second axis, and wherein the second line is parallel to the first axis and intersects the second axis, wherein the second radius is smaller than the first radius, and wherein the dome includes a central segment extending between the first axis and the outer segment, wherein the central segment is formed from a material to pass light at a wavelength interval, wherein the central segment includes an undulated segment; and wherein the central segment meets the outer segment to define a first plane, wherein the first plane is offset in a direction toward a reference plane defined by the second axis in relation to a second plane, parallel to the first plane, defined by the curvature of the outer segment.
21. A device comprising: a dome having an outer segment and a central segment, wherein the dome is formed from a material to pass light at a wavelength interval, wherein the dome has rotational symmetry around a first axis along a first angle, wherein the outer segment of the dome has a shape defined by a second axis, wherein the second axis is orthogonal to the first axis, is curved, and is located at a first radius from the first axis, wherein the outer segment is curved and is located at a second radius from the second axis over a second angle, wherein the central segment extends between the first axis and the outer segment, wherein the central segment is formed from a material to pass light at a wavelength interval, wherein the central segment includes an undulated segment, and wherein the central segment forms a central dome under which the central segment is configured to house one of the monitoring cameras.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic sectional view of a dome according to a first embodiment.
[0023] FIG. 2 is a detail view of a dome of the first embodiment with a monitoring camera arranged inside of it.
[0024] FIG. 3 is a schematic sectional view of a monitoring camera system according to a first embodiment.
[0025] FIG. 4 is a schematic sectional view of a dome according to a second embodiment.
[0026] FIG. 5 is a schematic plan view of the dome according to the first embodiment.
[0027] FIG. 6 is a schematic plan view of a dome according to a third embodiment.
[0028] FIG. 7 is a schematic plan view of a dome according to a fourth embodiment.
[0029] FIG. 8 is a schematic plan view of a monitoring camera arrangement.
[0030] FIG. 9 is a perspective view of a monitoring camera arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] FIG. 1 illustrates a dome 102 according to a first embodiment of the present invention. The view is a schematic cross section and there is rotational symmetry around the axis S1 as indicated in the drawing. The shape of the dome 102, as seen in cross section, is defined by a second axis of symmetry, located at a first radius R from the first axis of symmetry S1 and being orthogonal thereof. The second axis of symmetry is at a distance R from the first axis of symmetry, meaning that the second axis of symmetry for obvious reasons will have the form of a circle when seen in a plan view. Starting from the right and moving towards the first axis of symmetry S1 the shape of the dome as illustrated in FIG. 1 is defined by a first segment represented by an arc following a first radius from the second axis of symmetry over an angle β. The first segment connects to a central segment following an essentially straight line extending the shortest distance to the first axis of symmetry. The portion to the left of the first axis of symmetry S1 is for obvious reasons the mirror image of the portion just described.
[0032] In FIG. 2 a partial view of a monitoring camera system is shown. Comparison to FIG. 1 clarifies that the view of FIG. 2 represents the right portion of the view of FIG. 1, illustrating the dome 102 and the second axis of symmetry S2. A camera 104 is arranged within the dome 102 and the camera is shown in two positions (illustrated by the reference numerals 104 for the camera in the first position and 104′ for the camera in the second position) between which it has been rotated in a tilt, direction. The camera 104 has a tilt axis T defining the axis around which it may perform a rotational motion in a tilt direction. The camera 104 is arranged such that the tilt axis T coincides with the second axis of symmetry S2 ensuring that the distance between the camera and the first segment of the dome is constant as the camera 104 is tilted. In FIG. 1 the second axis of symmetry S2 is represented by a point, which is enough for explaining the cross sectional shape of the dome 102. In the more practical embodiment of FIG. 2 there may be a conflict between the curved second axis of symmetry S2 and the rectilinear tilt axis T of the camera in that a curved axis could not actually coincide perfectly with a rectilinear axis, at least not in the literal sense of the word. For that reason the interpretation of “coincide” is not to be interpreted literally. In a practical case the rectilinear tilt axis T is arranged in a tangential direction to the second axis of symmetry S2, and it may e.g. be arranged such that a center point of the axis T coincides with the axis S2. Tolerances may result in that the axes do not coincide in a point, and other considerations may also result in the same thing,
[0033] FIG. 3 illustrates a monitoring camera system where at least two cameras are arranged. The dome 102 as well as the tiltable cameras are recognized from the previous description and should need no further introduction. It may be emphasized that both cameras are arranged as the camera of FIG. 2. Adding to the previously described components a base 106 has been added. The base 106 acts as a carrier for the dome 102 as well as the cameras 104. Furthermore a central console 108 is arranged in which electronics, processing hardware and communication hardware, all denoted 110 may be arranged. The central console 108 will at least serve the dual purpose of protecting the components therein at the same time as it cancels out internal reflections within the dome and thus reduces glare and similar effects. Such effects may deteriorate the quality of imaging, and they may also trigger false events, e.g. a motion-detection algorithm could mistake a reflection for an actual movement. The central console 108 is aligned with the central segment C of the dome, such that at least a portion of the central console 108 overlaps with at least a portion of the central segment C as seen in a plan view. In the illustrated embodiment the central console 108 is completely overlapped by the central segment C, again as seen in a plan view. The full or partial overlap results in that the central console 108 may serve a third purpose: If there is an impact on the dome 102, e.g. as a result of someone hitting the dome, the dome will flex inwardly towards the cameras and components arranged therein. This could potentially disturb the alignment of one or more of the cameras, or even physically affect other components of the monitoring camera system resulting in malfunction, loss of connection or failure of operation. Instead, with the present setup, the central portion C of the dome 102 will engage with the central console 108 and the impact may be transferred to and absorbed by structural components not negatively affected by it, thus sparing the integrity and functionality of the camera system. Surfaces of the central console that may come into contact with the dome, such that the rim facing the dome, could be covered or lined with a resilient material. Another straight forward use of the console is for hiding wiring and cables, e.g. any surplus cable slack from the cameras may be hidden under the console. In yet another embodiment (not shown) the central segment of the dome, or at least a portion thereof, may be absent, and the central console may comprise an attachment for a post or similar. In this way the camera system may be readily arrange on a post. Such an arrangement may be realized in an embodiment where there is no central console as well, and the attachment does not necessarily have to be arranged on the central console. In a related embodiment (not shown) means for attachment to a post or similar are arranged on the central segment instead, or as a replacement of the central segment. In an embodiment from the same family of embodiments the angle β may extend 180° or at least significantly more than 90°. In versions of such embodiment the dome may extend down to a base along its outer perimeter (as for the illustrated embodiments) and along its inner perimeter. A post may then be attached directly to the base as well. In still another alternative embodiment the base may be annular as well such that the post may extend through the middle of the base. In another embodiment the monitoring camera system may be configured to be suspended from above, e.g. pending down from a post. In such a configuration the angle β may extend up to 180° (or even more), and the electronics may be arranged within the base.
[0034] FIG. 4 is a view similar to that of FIG. 1 yet of a dome 102′ according to a second embodiment, representing actually a second set of embodiments. In this second set of embodiments the central segment C′ has an undulated design. In the illustrated embodiment the dome still has rotational symmetry, yet in other embodiments an area defined by the central segment C′ may have undulations or a shape that is non-symmetrical. One reason for providing the central segment with undulation of some sort may be to improve the dome's ability of absorbing an impact. Sharp edges may create areas of concentrated strain during an impact or deformation, thus increasing the risk of breakage.
[0035] FIGS. 5-7 illustrate three embodiments where the angle α is altered. In the embodiment of FIG. 5 α equals 360°, representing an embodiment that may be arranged in a ceiling and enabling arrangement of e.g. 4 cameras or more within the dome for a full 360°-view. Fewer than cameras four or more may of course be arranged, such as 3, 2 or 1. In the embodiment of FIG. 6 α equals 180°, representing an embodiment that may be arranged in a ceiling, where the ceiling meets a wall. Two or more cameras may be arranged to cover a suitable field of view, while of course fewer cameras or a higher number of cameras may be arranged as well. An embodiment suitable for arrangement in a corner is illustrated in FIG. 7, where α equals 90°.
[0036] In another set of embodiments the angle β may be varied, β defining the angular extension of the first segment starting from the outermost perimeter (e.g. the ceiling against which it is arranged), as exemplified in FIG. 1. In essence variation of the angle β will affect the possibilities of tilting a camera arranged inside the dome. For specific cases the angle β may be significantly smaller than 90°, and it may also be slightly smaller than 90° or equal to 90°. In the embodiments illustrated thus far the angle β is slightly larger than 90°, enabling a tilt angle for the camera that may vary between 0 and 90°, or even above. In effect this means for a camera system arranged in a ceiling the cameras may have a field of view ranging from looking along the ceiling and also looking straight down below the camera system, and even a bit further in the embodiments where the angle is slightly larger than 90°, thus a suitable arrangement of monitoring cameras under single dome may provide a full coverage of views in this context it may be mentioned that prior art solutions generally offer more complex and bulky or less versatile alternatives. A typical prior art solution is presented in US20130100292, representing a common compound solution, where the dome is divided into separate functional portions. In terms of functionality the prior art solution may be comparable, depending on the cameras used, but it will be significantly more complex, have a higher number of joints and will have a more noticeable geometrical profile.
[0037] FIG. 8 illustrates a schematic plan view of a monitoring camera system comprising features already described, having four monitoring cameras arranged with their respective tilt axis T aligned with the second axis of symmetry S2. The tilt will be affected in the same plane as the angle β, and vice versa, at least in the preferred embodiments. The cameras may be powered from a central power supply arranged in the middle of the arrangement (in the central console 108), and connected to processing arrangements therein for processing of image data. This enables that a simple and straightforward connection by means of physical cables may be used while still providing full versatility. Notwithstanding this beneficial feature obviously more complex solutions, such as wireless systems or a slip ring arrangement, may be used without departing from the inventive concept.
[0038] To increase the versatility of the monitoring camera system it may be preferred that the cameras are arranged on a guide rail or similar, enabling continuous or indexed movement between different static camera positions. Such a feature allows for a tailor made coverage of a particular scene, and a use of a guide rail also ensures the alignment between the tilt axis T and the second axis of symmetry S2. There are several options for the guide rail, ranging from a series of threaded openings to an actual rail to which the cameras may be secured by means of magnets, clamps or screw arrangements, and reference is made to EP2887328 to the present applicant relating to a magnetic rail.
[0039] The dome itself may be manufactured from polycarbonate or another suitable material, and components such as the base may be manufactured from plastic or metal, or a composite material. The choice of material may be adjusted depending on a particular application, yet for most purposes the choice of material may be limited to materials commonly used within the established field of dome cameras. A typical thickness for the dome may be 1-3 mm, typically about 2 mm. Injection moulding may be a suitable method for manufacturing the dome.
[0040] FIG. 9 illustrates a monitoring camera system 100 in a perspective view thereof. The dome 102 is indicated rather than fully illustrated to the benefit of components arranged below it. Several monitoring camera heads 104 are seen arranged on a guide rail 112 via a mount 114. The camera heads are pivotally arranged on the mount, thus providing the tilt axis T. In the view of FIG. 9, the central console has been removed to allow visual access to the components arranged therein. There are obviously several different ways of obtaining the same or similar functionality yet for the purposes of enabling the present invention as disclosed herein the embodiment illustrated in FIG. 9 is a viable alternative. The cameras may have lenses being of fixed focal length, or being varifocal, yet other alternatives are not excluded. For example, a camera arranged below (within) the central segment may have a lens of a wide-angle type, one example being a fisheye lens.
