Patent ID: 8933405
Filing Date: 2015-01-13
Classification: G01N

Abstract:
1. Apparatus for detecting a concealed object in an article comprising: a source of Near Infra-Red (NIR) radiation operable to illuminate an article to be inspected; a detector, the detector being configured to detect that portion of the source beam incident on the detector that has been passed through at least a portion of the article; a collimator, the collimator having an entrance aperture, the collimator being arranged to collimate light passing through the entrance aperture that has passed through the article before it reaches the detector; and control means for detecting by means of the detector an intensity of NIR illumination incident on the detector and to identify the presence of a concealed object in an article responsive to a variation in detected intensity across at least a portion of the article, wherein the control means is arranged to detect a concealed object not by imaging nor by a single point measurement or single measurement of the integrated total transmitted radiation through the whole of the object but by evaluation of the whole of the article with reference to variances in transmitted radiation through a least part of an article but without spatial reference to said least part of the article; and wherein the detector comprises a plurality of photodetectors, respective photodetectors having an optic axis substantially coincident with an optic axis of a corresponding source element.