Image system designed to scan for security threats

• US 8,897,599 B2
• Filed: 06/11/2010
• Issued: 11/25/2014
• Est. Priority Date: 06/12/2009
• Status: Active Grant

• Current Assignee: Smiths Detection Ireland Limited
• Original Assignee: Smiths Detection Ireland Limited
• Inventors: Abdillah, Mohammed Ben, Entchev, Emil, Widera, Adam, McNaboe, John, Lyons, Brendan, Volz, Claudius, Dreiseitel, Pia, Meder, Claus
• Primary Examiner(s): Allison, Andrae S
• Application Number:
  US13/376,406
• Publication Number:
  US 20120093438A1
• Time in Patent Office: 1,628 Days
• Field of Search: 382128-132, 382/154, 382/276, 382/286, 342/22, 342/27, 342/179, 342/376, 378/41, 378/57
• US Class Current: 382/286
• CPC Class Codes: G01S 13/887 for detection of concealed objects, e.g. contraband or weapons
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 7/295 Means for transforming co-ordinates or for evaluating data, e.g. using computers
• CPC Class Codes: G01V 8/005 operating with millimetre waves, e.g. measuring the black losey radiation

Abstract

An imaging system comprises a transmitter (24, 25), a receiver (24, 25, 21), and a controller (20) for directing the transmitter and the receiver to scan an object in a volume. The controller determines which sub-volumes of the volume the object is located within and then performs a fine scan in those sub-volumes. This reduces overall scanning time. The controller (20) may compare a received signal sample magnitude from the initial scan with a threshold to make the decision. The initial scan may be performed with a spot size to include only one or more particular volume elements within at least some of the sub-volumes.

Claims

1. An imaging system comprising:

a transmitter

a receiver

an array of reflectors,

a controller for directing the transmitter, the receiver, and the reflectors to scan an object in a volume,

wherein the controller determines which sub-volumes of said volume the object is located within and to perform a fine scan in said sub-volumes,

wherein the controller initially scans the volume using the transmitter, the receiver, and the reflectors to use said initial scan to decide which sub-volumes the object is located within, and to then perform the fine scan in said sub-volumes, again using said transmitter, receiver, and reflectors;

wherein the controller compares a received signal sample magnitude from the initial scan with a threshold to make said decision; and

wherein the controller directs the transmitter and the receiver to perform the initial scan with a spot size to include only one or more particular volume elements within at least some of the sub-volumes.

2. The imaging system of claim 1, wherein the controller additionally performs a fine scan of sub-volumes adjoining those determined to include the search object.

3. The imaging system of claim 2, wherein the controller additionally performs a fine scan of sub-volumes neighbouring those sub-volumes which adjoin those determined to include the search object.

4. The imaging system of claim 1, wherein said volume elements include a volume element which is central within at least some sub-volumes.

5. The imaging system of claim 1, wherein said volume elements include a plurality of particular volume elements in at least some sub-volumes.

6. The imaging system of claim 1, wherein said volume elements are selected in a pre-defined pattern.

7. The imaging system of claim 1, wherein said volume elements are selected in a random pattern.

8. The imaging system of claim 1, wherein the controller directs the transmitter and the receiver to perform the initial scan with a spot size encompassing a full sub-volume size.

9. The imaging system of claim 1, wherein the controller is connected to the arrays of reflectors in a daisy-chain arrangement for bi-directional control communication.

10. The imaging system of claim 1, wherein the controller is connected to the arrays of reflectors in parallel for uni-directional control and timing signals.

11. The imaging system of claim 1, wherein the controller controls a scan spot size for a fine scan to encompass a full sub-volume which is deemed to include the object.

12. The imaging system of claim 11, wherein the controller controls focus using control of the reflectors.

13. The imaging system of claim 1, wherein the system determines said sub-volumes at least in part using a sensing system which is separate from the transmitter and the receiver.

14. The imaging system of claim 1, wherein the controller initially scans the volume and perform the fine scan in said sub-volumes by:

reflecting an incident beam from the transmitter along an incident path onto the object using the array of reflectors, radiation reflected from the object re-traverses the incident path to the array of reflectors, wherein the radiation reflected from the object is redirected to the receiver.