Directional imaging using camera positioning in light fixtures for minimizing protective window size
View Patent ↗The specification and drawings present a light fixture for an imaging camera, where a protective window size requirements for camera imaging in a wide field of view (WFOV) are minimized using directional imaging through the protective window. This can be accomplished by a camera position adjustment according to a predefined algorithm as described herein. This adjustment may be performed using a mechanical motor or manually (using corresponding screws, lever, etc.) to actuate a mechanical mechanism. For example, a four-bar linkage mechanism may be used, which may allow the camera to pivot about a virtual pivot point (or generally, a pivotal area) generated by the intersection of the camera lens bore sight axes (camera lens central axes), e.g., outside of a housing of the light fixture.
1. A light fixture comprising:
a housing comprising a protective window transparent to light and having predefined dimensions;
a camera, inside of the housing, configured to provide images of surroundings of the light fixture through the protective window to cover a wide field of view (WFOV) which is substantially larger than a field of view (FOV) of the camera when moving the camera along a predefined trajectory, where at any position of the camera along the predefined trajectory, light rays received by the camera in the camera FOV are within a substantially same area of the protective window and not shadowed by non-transparent edges of the protective window, where the predefined trajectory is defined by movement in a three-dimensional space of two points, and the camera position is defined by the two points at a given time; and
a mechanical module, holding the camera, configured to move the camera along the predefined trajectory.
2. The light fixture of claim 1 , wherein the two points are located on a central axis of the camera.
3. The light fixture of claim 1 , wherein the trajectory is located in a two-dimensional plane, so that the two points are moved in the two-dimensional plane.
4. The light fixture of claim 1 , wherein the trajectory is located in the three-dimensional space, so that the two points are configured to move at least in two two-dimensional planes.
5. The light fixture of claim 4 , wherein the pivot point or the predefined pivotal area around the pivot point is located outside of the housing.
6. The light fixture of claim 1 , wherein, when the camera moves along the predefined trajectory, a central axis of the camera swivels around a pivot point or a predefined pivotal area around the pivot point.
7. The light fixture of claim 1 , wherein the movement for each of the two points is a circular path at least in one plane.
8. The light fixture of claim 1 , wherein, wherein the movement for each of the two points is an elliptical path at least in one plane.
9. The light fixture of claim 1 , wherein the protective window has a circular shape.
10. The light fixture of claim 1 , wherein the protective window has a rectangular shape.
11. The light fixture of claim 1 , wherein the mechanical module comprises one mechanism to provide a two-dimensional movement of the camera in one plane.
12. The light fixture of claim 11 , wherein the mechanical module comprises a further mechanism to provide a further two-dimensional movement of the camera in a further plane, such that both the one and further mechanisms together provide the three-dimensional movement of the camera.
13. The light fixture of claim 12 , wherein the further mechanism comprises a further four-bar linkage mechanism.
14. The light fixture of claim 11 , further comprising a servo motor configured to activate the one mechanism.
15. The light fixture of claim 11 , wherein the one mechanism comprises a four-bar linkage mechanism.
16. The light fixture of claim 11 , further comprising a step motor configured to activate the one mechanism.
17. The light fixture of claim 11 , wherein the one mechanism is actuated by a linear actuator.
18. The light fixture of claim 11 , wherein the one mechanism is actuated by a screw thread.
19. The light fixture of claim 11 , wherein the one mechanism is actuated by a mechanical lever.
20. The light fixture of claim 11 , wherein the one mechanism is actuated by an elliptical cam and follower.