| 摘要 |
A system and device perform a method for monitoring the accessibility of an emergency exit, which includes illuminating an area in front of the emergency exit by emitting light, detecting reflected light from the illuminated area using an image sensor, calculating a plurality of distances based on the detected reflected light for discrete positions in the image sensor, comparing the each of the plurality of distances with a predetermined distance, and generating an alarm signal if the comparing indicates a substantial difference in distance in at least one position in the image sensor. |
