Patent ID: 9562866
Date: 2017-02-07
CPC Classifications: G01N,G01V,G21K

Claim:
1. A system for detecting concealed threats in an object by simultaneously performing active and passive radiation detection, the system comprising: an X-ray source with a modulating device to produce a pencil beam of radiation for scanning the object, said modulating device configured to block the pencil beam at regular intervals; a distance sensor adapted to emit a beam of light and adapted to determine a plurality of times for said light to scatter off a plurality of surfaces of said object and return to said sensor, wherein said plurality of times are indicative of a plurality of distances from said distance sensor to said plurality of surfaces; a detector module for generating signals indicative of radiation backscattered by the object when the object is scanned with the pencil beam of radiation and for generating signals indicative of passive radiation that is emitted from threats within said object when the pencil beam of radiation is blocked, wherein said detector module comprises at least one detector; and a controller configured to cause said system to measure backscattered radiation only when the x-ray pencil beam is on, and to measure only passive radiation when the x-ray pencil beam is blocked, wherein said controller further uses the plurality of distances to implement an adaptive region based averaging method such that a size of each region is a function of a distance to the X-ray source thereby resulting in signals from regions far from the X-ray source being averaged over a larger region.