| 摘要 |
A sensor arrangement (15 in fig. 1) captures first and second images 23 and 22 of a moving object in proximity to the target (33 or 10 in fig. 1). A processing module receives the first and second image from the sensor arrangement and calculates the position and velocity of the moving object before comparing these with at least one real or imaginary positional threshold (32, 31, 30). The processing module is also arranged to generate a control signal in response to the calculated position and velocity satisfying a criterion with respect to the positional threshold (e.g. if the object s approach crosses the threshold). This invention provides the generation of a control (e.g. door opening) signal when a target (e.g. door) is validly approached by a moving object (e.g. a person walking towards the door), but not when the approach is invalid (e.g. a person walking past the door or entrance). |
