US Patent 7397504 Whiteboard view camera

A whiteboard view camera, which in one embodiment is mounted on a boom, which is fixed above the whiteboard. However, the whiteboard view camera can also be wall or table mounted. The whiteboard view camera differs from an ordinary camera by allowing the lens to tilt with respect to the sensor plane, and shift with respect to the central ray. When the tilt angle α is zero, then the resolution of whiteboard is uniform (e.g., the top and bottom of the whiteboard have the same resolution). In addition, the focus plane is equal to the whiteboard plane, so depth of field issues are not a problem (e.g., a large aperture can be used). Hence, no image noise is introduced. A key contribution of the whiteboard view camera configuration according to the invention is the use of a view camera to capture whiteboard images at uniform resolutions. One embodiment of the whiteboard view camera employs a microphone array of the invention and uses a computer to optimize the image data and audio signals.