Security system and method of detecting contraband items

• US 10,276,008 B2
• Filed: 12/16/2015
• Issued: 04/30/2019
• Est. Priority Date: 12/18/2014
• Status: Active Grant

• Current Assignee: Metrasens Incorporated
• Original Assignee: Metrasens Incorporated
• Inventors: Keene, Mark Nicholas, Goodyear, Simon Wray
• Primary Examiner(s): Tweel, Jr., John A
• Application Number:
  US15/537,759
• Publication Number:
  US 20180012465A1
• Time in Patent Office: 1,231 Days
• Field of Search: 3405681
• CPC Class Codes: G01V 3/08 operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices with electromagnetic waves G01V3/12
• CPC Class Codes: G01V 3/087 the earth magnetic field being modified by the objects or geological structures
• CPC Class Codes: G08B 1/08 using electric transmission ; transformation of alarm signals to electrical signals from a different medium, e.g. transmission of an electric alarm signal upon detection of an audible alarm signal
• CPC Class Codes: G08B 13/22 Electrical actuation
• CPC Class Codes: G08B 13/24 by interference with electromagnetic field distribution
• CPC Class Codes: G08B 15/001 Concealed systems, e.g. disguised alarm systems to make covert systems
• CPC Class Codes: G08B 5/36 using visible light sources
• CPC Class Codes: G08B 6/00 Tactile signalling systems, e.g. personal calling systems
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source
• CPC Class Codes: H04N 7/188 Capturing isolated or intermittent images triggered by the occurrence of a predetermined event, e.g. an object reaching a predetermined position signal generation from motion picture films H04N5/253

Abstract

A security screening apparatus for use in detecting ferromagnetic objects comprises a detector apparatus which comprises a housing that supports at least one magnetic sensor arranged to produce a signal indicative of an ambient magnetic field or gradient over a zone of sensitivity which extends away from the housing, the size of the zone being large enough to contain the whole body of the person, and a signal processing circuit which receives as an input the signal from the magnetic sensor and which, in response to a change in the signal produces an alert signal. A beacon that comprises a light source is able to emit at least two visually distinct colors of light, and a control means controls the light source such that in a first condition in the absence of the alert signal the beacon emits a first color light and in a second condition corresponding to the presence of the alert signal the beacon emits a second, different, color of light. The light source is arranged such that the position and/or size and/or shape of the illuminated area of the light source in the first condition is different from the position and/or size and or shape of the illuminated area of the light source in the second condition.

Claims

1. A security screening system comprising:

a detector apparatus comprising at least one magnetic sensor arranged to produce a signal indicative of an ambient magnetic field or gradient over a zone of sensitivity around the sensor, the zone being large enough to contain a whole body of a person; and

a signal processing circuit which receives as an input the signal from the magnetic sensor and which, in response to a change in the signal produces an alert signal;

characterised in that the detector apparatus includes a transmitter that transmits a non-visible and non-audible warning signal when the alert signal is produced, wherein the warning signal is not detectable by the receiver of a mobile phone, including any Bluetooth detector that may be located in a mobile phone, the system further comprising;

a remote warning device that is physically separate from the detector apparatus and comprises a receiver that is responsive to the transmitted warning signal issued by the detector module and generates a remote alert signal when the warning signal is received, whereby the alert signal can be associated with a person or object in the detection zone of the apparatus.

2. The security screening system according to claim 1 wherein the detector apparatus includes a beacon that is switchable between an inactive state in which the beacon does not respond to the alert signal and an active state in which the beacon responds by generating an audible, visible or audio/visual warning signal configured so that the beacon may be switched to the inactive state whilst the remote warning device is active, so that a person observing the security screening system is fooled into thinking that it is not operating or has not detected anything.

3. The security screening system according to claim 1 wherein the transmitted signal comprises an electromagnetic or ultrasonic or infra-red signal.

4. The security screening system according to claim 1 wherein the transmitted signal has a relatively short range so that it will alert a nearby guard who is carrying or wearing the remote device, but cannot be detected outside of the range.

5. The security screening system according to claim 1 wherein the remote alert device is a transducer that vibrates when the alert signal is generated to generate a haptic signal.

6. The security screening system according to claim 1 wherein the transmitted signal has a long range to alert a distant guard.

7. The security screening system according to claim 1 which comprises a plurality of a detector apparatus, each of which comprises at least one magnetic sensor arranged to produce a signal indicative of an ambient magnetic field or gradient over a zone of sensitivity around the sensor, the zone being large enough to contain the whole body of the person, and a signal processing circuit which receives as an input the signal from the magnetic sensor and which, in response to a change in the signal produces an alert signal;

and in which each detector apparatus includes a transmitter that transmits a non-visible and non-audible warning signal when the alert signal is produced, and further comprising;

at least one camera that captures images of the area including the detector apparatus or a region adjacent the apparatus in which a person approaching, within or having passed through the zone of sensitivity may be located,

at least one display monitor on which the images captured by the camera can be displayed, and

a controller that is responsive to the remote alert signal to cause the image from the camera associated with the detector apparatus that has generated the alert to be displayed on the monitor.

8. The security screening system according to claim 7 further comprising a camera for each detector apparatus, each camera capturing an image of a region adjacent the apparatus in which a person approaching, within or having passed through the zone of sensitivity may be located.

9. The security screening system according to claim 7 in which the camera comprises a video camera and the camera and monitor that form part of closed circuit television security system.

10. The security screening system according to claim 7 wherein the detection apparatus is configured to transmit an alert signal through a CCTV system.

11. The security screening system according to claim 7 wherein the camera has sensitivity to the near infra-red and the detector apparatus includes a visual warning beacon that includes infrared LEDs to be lit so as to emit an infrared light alert signal.

12. The security screening system according to claim 7 wherein the detection apparatus includes a near-ultrasonic transmitter that transmits the alert signal, i.e. 20-22 kHz, which is just beyond the maximum hearing range for a human and associated with each detector apparatus is a microphone that can hear such an alert signal.