Object movement detection method for anti-intruder security systems, by comparing distance between optical measuring device and object with reference value

摘要

The distance between an object and a measuring device (31, 34) is measured optically, preferably using laser light, the measured distance is compared with a reference value and the object is regarded as moving if the measured distance differs from this reference value. The reference value is a previous distance measurement for the same object. Independent claims are also included for the following: (a) a method for detecting a moving object on a terrain by measuring a distance profile for the terrain relative to the measuring device and comparing the measured profile with a reference profile; (b) a method for locally verifying a report of an incident on a terrain by receiving a report signal indicating a possible incident has been detected and including information relating to the direction and distance of this incident and then focusing a camera in this direction; (c) a method for monitoring a terrain by detecting a possible incident and generating a report signal including information relating to the direction and distance of this incident, using a camera and automatic image recognition to locally verify the report and sending camera images to an external verification system (5); (d) a primary detection system (3) for detecting a moving object, comprising a light source for emitting a pulsed light beam (preferably a laser), a sensor for detecting reflected light, a processing device for receiving an output signal from the sensor and generating a report signal if a change in distance between a light-reflecting object and the light source and sensor is detected; (e) a primary detection system for detecting a moving object on a terrain by measuring a distance profile for the terrain relative to the measuring device and comparing the measured profile with a reference profile; (f) a local verification system (4) for verifying an incident report signal generated by a primary detection system and including information relating to the incident location (i.e. direction and distance), comprising a preferably digital camera, a camera control circuit connected to a report signal input and a camera control input so that the camera can be pointed at and focused on the incident; (g) an external verification system (5) comprising a communication means for receiving an image signal from a local verification system via a communication link (6), a screen for displaying the image signal to monitoring personnel, a communication means for the monitoring personnel to alert security personnel (7) to investigate the incident and preferably a memory device for storing the image signal; (h) an alarm system (2) comprising a primary detection system for detecting a possible incident and a local verification system connected and operating according to a different principle to the primary system, used for verifying the incident, so that an alarm signal is only generated if the incident is verified; (i) a verification system (8) for verifying a possible incident detected by a primary detection system and alerting security personnel if the incident is verified, comprising local and external verification systems connected via a communication link for sending image signals from the local system to the external system so that they can be displayed to monitoring personnel who can alert the security personnel; and (j) a security system (1) comprising the alarm system, the local verification system, the external verification system and a communication link between the two verification systems.