# US 6,756,910 B2 · Sensor for automatic doors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,756,910 B2 - Document ID: US6756910B2 - Status: Granted - Kind: B2 - Application number: 10/083,571 - Filed: 2002-02-27 - Published: 2002-08-29 - Granted: 2004-06-29 - Earliest claimed: 2001-02-27 - Assignees: Optex Co., Ltd. - Inventors: Hiroyuki Ohba; Yoshihiro Imuro; Osamu Imanishi; Mataichi Kurata - Web page: https://patentgrep.com/patent/US6756910B2 ## CPC - G01V 8/10: Detecting, e.g. by using light barriers (by reflection from the object G01S17/00) - E05F 15/43: responsive to disruption of energy beams, e.g. light or sound - E05F 15/73: responsive to movement or presence of persons or objects - E05F 2015/434: {with cameras or optical sensors} - E05F 2015/767: {using cameras} - E05Y 2900/132: Doors - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - E05F: DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION; CHECKS FOR WINGS; WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING - E05Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES E05D AND E05F, RELATING TO CONSTRUCTION ELEMENTS, ELECTRIC CONTROL, POWER SUPPLY, POWER SIGNAL OR TRANSMISSION, USER INTERFACES, MOUNTING OR COUPLING, DETAILS, ACCESSORIES, AUXILIARY OPERATIONS NOT OTHERWISE PROVIDED FOR, APPLICATION THEREOF ## Abstract Cameras take images of a predetermined area around a door. A distance measurement unit measures a distance from the cameras to each object in the taken images. Based on the measured distance, a floor detection unit detects a floor, and an object height/position detection unit detects a height and position of any object other than the floor. A door position detection unit and a door position identification unit 57 specify position of the door (i.e. open or closed) in the images taken by the cameras. A judgement unit judges presence or absence of an object which is neither the floor nor the door. If an object other than the floor and the door is observed in the images taken by the cameras, an output unit produces an object detection signal, so that the door is kept in an open state. ## Claims ### Claim 1 A sensor for an automatic door, comprising: image pickup means for taking an image of a predetermined area around a door; distance measurement means for, upon receiving an output from said image pickup means, measuring a distance between said image pickup means and each object which is in the predetermined area and observed in the image taken of the predetermined area; object identification means for, upon receiving an output from said distance measurement means, identifying each object in the predetermined area, for which the distance between it and said image pickup means has been measured, as a background object or an object other than the background object based on the measured distance, and identifying the object other than the background object as the door or an object other than the door; and output means for, upon receiving an output from said object identification means, outputting an object detection signal for an object that is observed in the image taken of the predetermined area and is neither the background object nor the door. ### Claim 2 (depends on 1) The sensor for an automatic door according to claim 1, wherein the sensor is associated with door drive control means for controlling an open/close drive of the door, and wherein said output means is for outputting the object detection signal to said door drive control means so as to cause the door to open fully. ### Claim 3 (depends on 2) The sensor for an automatic door according to claim 2, wherein said image pickup means includes plural image pickup elements; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements. ### Claim 4 (depends on 2) The sensor for an automatic door according to claim 2, wherein said image pickup means has a variable focus lens; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object. ### Claim 5 (depends on 1) The sensor for an automatic door according to claim 1, wherein said image pickup means includes plural image pickup elements; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements. ### Claim 6 (depends on 1) The sensor for an automatic door according to claim 1, wherein said image pickup means has a variable focus lens; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object. ### Claim 7 A sensor for an automatic door, comprising: image pickup means for taking an image of a predetermined area which covers a track of a door; distance measurement means for, upon receiving an output from said image pickup means, measuring a distance between said image pickup means and each object which is in the predetermined area and observed in the image taken of the predetermined area; floor detection means for, upon receiving an output from said distance measurement means, detecting a floor and a height and position of the floor such that the floor is distinguished from objects for which the distance between these objects and said image pickup means has been measured; object height/position detection means for, upon receiving outputs from said distance measurement means and said floor detection means, detecting a height and position of an object, other than the floor, which is in the predetermined area and observed in the image taken of the predetermined area, and is located at a different height and position relative to the height and position of the floor; door position detection means for detecting whether the door is in an open position or a closed position along the track; door position identification means for, upon receiving an output from said door position detection means, identifying a position of the door in the image taken of the predetermined area, based upon whether the door is in an open position or a closed position as detected by said door position detection means; judgement means for, upon receiving outputs from said object/height position detection means and said door position identification means, judging whether the object, which is other than the floor, is the door or an object other than the door; and output means for, upon receiving an output from said judgement means, outputting an object detection signal for an object that is observed in the image taken of the predetermined area and is neither the floor nor the door. ### Claim 8 (depends on 7) The sensor for an automatic door according to claim 7, wherein the sensor is associated with door drive control means for controlling an open/close drive of the door along the track and for producing an output signal which corresponds to the position of the door, and wherein said door position detection means is for receiving the output signal from said door drive control means so as to determine whether the door is in an open position or a closed position. ### Claim 9 (depends on 7) The sensor for an automatic door according to claim 7, wherein said door position detection means is for determining whether the door is in an open position or a closed position based on the image of the predetermined area taken by said image pickup means. ### Claim 10 (depends on 7) The sensor for an automatic door according to claim 7, wherein the sensor is associated with door drive control means for controlling an open/close drive of the door along the track, and wherein said output means is for outputting the object detection signal to said door drive control means so as to cause the door to open fully. ### Claim 11 (depends on 10) The sensor for an automatic door according to claim 10, wherein said image pickup means includes plural image pickup elements; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements. ### Claim 12 (depends on 10) The sensor for an automatic door according to claim 10, wherein said image pickup means has a variable focus lens; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object. ### Claim 13 (depends on 7) The sensor for an automatic door according to claim 7, wherein said image pickup means includes plural image pickup elements; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, via stereo image processing which utilizes parallax of images taken by said plural image pickup elements. ### Claim 14 (depends on 7) The sensor for an automatic door according to claim 7, wherein said image pickup means has a variable focus lens; and wherein said distance measurement means is for measuring a distance from said image pickup means to each object, which is in the predetermined area and observed in the image taken of the predetermined area, based on a degree of focus of this object.