EmbedTek Invents Reflective Progressive Lens
EmbedTek filed a provisional patent for a camera system including a reflective progressive lens. The system captures images of people, vehicles, or objects that would be blurred or lack enough detail with standard camera technology and lenses.
In some constructions, the camera system can use the non-linear progressive lens that EmbedTek has filed a separate provisional patent for. The non-linear progressive lens and the reflector can work together to capture and process a final image that only includes pixels from a defined area within the field of view. This avoids wasting pixels on an undesired zone outside of the frame.
Both inventions are ideal for improving the capabilities of video surveillance, where the need to identify objects near and far from the camera are critical. For example, when monitoring a roadway, EmbedTek’s progressive surveillance camera system can capture and focus on identifying the cars on the road and ignore the tree line, sky and unimportant ditches. And when monitoring a warehouse, the progressive surveillance camera system can focus on identifying people, vehicles, and objects in the aisle and not waste pixels on the storage racks and walls that surround it.
The camera system with progressive reflective lens invention for this specific application consists of:
- A camera with a lens positioned above an area
- One or more camera sensors with an aspect ratio defined by the total number of pixels in the X-Y plane for the camera sensors
- A reflector specifically constructed to condense pixels of the lens to a desired zone of the area
- A processor
The reflector – which is a highly polished surface such as a mirror – adjusts the pixel distribution in an area of interest to view objects that are near to and farther away from a camera lens. The camera captures this altered frame through the lens and the altered frame is expanded so the pixels fill the aspect ratio of the camera sensor. The pixels are then processed and analyzed to produce a final image that will be used for machine vision applications.
The following example shows how the system can improve surveillance in a warehouse application. The field of view in this example includes a warehouse aisle and areas around it. The camera system with reflective progressive lens invention is not limited to this application.
Existing Cameras: Inadequate Identification
In general, the depth of field of existing cameras defines the area of the field of view that appears in focus. The scale of images taken with a typical camera technology is vertical, not linear, so objects farther from the camera appear much smaller than objects closer to the camera.
Also, the uniform pixel distribution of existing camera lenses causes the objects that are positioned relatively close to the camera, inside and outside the frame, to capture higher resolution than is necessary to view objects in those areas. At the same time, objects relatively far from the camera capture with a lower resolution than is necessary to adequately view relevant objects.
Figure 1 shows that existing technology, which is a camera positioned above the aisle to securely monitor the aisle, does not adequately provide the ability to readily identify the person (54) and the vehicle (58) in the same image.
The Reflective Progressive Lens Difference: Complete Visibility
The EmbedTek camera system with reflective progressive lens will capture and enhance only the desired area (the aisle) instead of wasting pixels in the undesired area (the storage racks on each side of the aisle and the wall in the distance).
After the unique profile of the reflector is constructed for the specific application, the camera and the reflector are positioned relative to an area to be monitored. The reflector condenses the pixels of the lens from the undesired zone to within the area of interest so that the camera captures only the desired zone. The portion of the altered frame relatively close to the camera has approximately the same pixels per square unit area as the portion relatively far from the camera. And because the altered frame has more pixels than the pixels associated with the initial frame, the altered frame has a higher resolution and clarity.
Figure 2 shows the camera system with reflective progressive lens positioned above the aisle in a warehouse. The reflector is constructed to condense the pixels within the aisle so the camera monitors the aisle without capturing the undesired zones. The desired zone is bounded by a frame that includes a continuous section of the aisle. As a result, the person and the vehicle, which are in different portions of the area, are both visible while monitoring the aisle.
The system is designed for each application and the technology is versatile. The system can capture any shape of a desired zone, can be mounted on any surface, and can capture any desired image or number of images. In some constructions, instead of a continuous zone such as the aisle in the warehouse example, the desired zone may be disjointed or unconnected portions of the area. In other constructions, instead of storing a final image, the processor may transmit it over a communication network to a display for personnel assigned to monitor the desired zone.
EmbedTek is currently applying its progressive lens and reflector technology as part of its design and development of complex vision systems. The engineering team continues to develop new system designs, non-linear lenses, and reflector constructions for a wide range of applications to remap each sensor pixel to be best utilized within a targeted area.This allows the use of less expensive sensors to capture better resolution within targeted areas. By using lower cost sensors wit this technology, many new OEM applications are now possible.