Patent ID: 6973998

Claim:
An apparatus for monitoring states of an elevator door comprising: a sensor for generating three-dimensional image information and including a light source and a sensor group, said sensor group including a plurality of light-sensitive elements detecting light emitted by said light source and reflected by a plurality of target points in a monitored space, a transit time of each of said emitted light pulses representing an associated distance between said sensor and an associated one of the target points, said distances forming said three-dimensional image information; and processing equipment connected to said sensor and being responsive to said three-dimensional image information for recognizing a deviation of said three-dimensional image information from reference information whereby when said sensor is mounted in a region of an elevator door which is to be monitored with the door disposed at least partly in a detection range illuminated by said light source, said processing equipment can categorize at least one state of the elevator door based upon said deviation.