Patent ID: 7042492

Claim:
An automatic door assembly for installation at a doorway formed through a wall of a building, said door assembly comprising: a frame assembly constructed and arranged to be mounted to the building wall at the doorway thereof; a door panel constructed and arranged to be mounted to said frame assembly for movement between (1) a closed position wherein said door panel is positioned in covering relation over the doorway to prevent persons and objects from travelling therethrough and (2) an open position wherein said door panel is moved out of said covering relation to permit persons and objects to travel through the doorway; a door controlling system comprising: (i) a video imaging device constructed and arranged to be mounted in a viewing position wherein said imaging device monitors a field of view that encompasses at least the door panel and a door panel travel area through which said door panel moves between said open and closed positions, said video imaging device being operable to monitor the field of view by receiving image of the field of view, including images of at least the door panel within the door travel area, in the visible light spectrum, said video imaging device transmitting a video data signal comprising information representative of said images; (ii) a detection system comprising a video signal processor that communicates with said video imaging device and a memory, said memory containing a plurality of stored initial images of at least the door panel within the door travel area, each of said stored initial images corresponding to one of a plurality of positions of the door panel within the door travel area, said video signal processor being adapted to receive said video data signal from said imaging device; and a door operator constructed and arranged to be connected to said door panel and adapted to communicate with said detection system, said door operator being constructed and arranged to move said door panel between the open and closed positions through said door panel travel area and to move the door panel towards said open position thereof responsive to receiving a door opening signal; a position sensor communicated to said processor for monitoring the plurality of positions of the door panel within the door panel travel area, each of the monitored positions of the door panel having a corresponding stored image in said memory of the door panel within the door travel area; the video signal processor being adapted to determine whether a person or object other than the door panel is within the door panel travel area by comparing at least the images of the field of view, including the door panel therein, received via the video data signal against the stored initial images of the door panel within the door travel area for the corresponding positions of the door panel as monitored by the position sensor, the processor using the compared images to determine that a person or object is within the door travel area.