Shoe scanning system for full-body scanner and method for retrofitting a full body scanner

A shoe scanning system for a restricted area access point, notably provided with a full-body scanner scanning an individual before access to a restricted access area, the system comprising a detection unit comprising:

• a flat casing having a top surface onto which the individual can walk, and a flat planar board located below the top surface;
• a main detector for sensing metal and/or unauthorized object(s) above the top surface of said casing;
• a communication unit for transmitting a message to an indication unit for providing instructions to the individual and/or to an assistant;
• and
• a processing unit connected to the main detector by a data link for receiving data and controlling the communication unit for sending a detection signal when the main detector indicates a presence of the metal and/or unauthorized object(s),
• wherein the main detector comprises sensing elements located on the flat planar board below said top surface, the sensing elements comprising:
• a short-range sensing element arranged on the flat planar board to detect the metal and/or unauthorized object(s) located above said surface up to a first maximal distance, said short-range sensing element having a first surface with a first surface area;
• and
• a long-range sensing element arranged on the flat planar board to detect the metal and/or unauthorized object(s) located above said surface up to a second maximal distance, the second maximal distance being higher than the first maximal distance, said long-range sensing element having a second surface with a second surface area larger than the first surface area of said short-range sensing element,
• wherein the processing unit is configured to determine a height of the detected potentially unauthorized objects based on a result provided by the short-range sensing element and a result provided by the long-range sensing element.

A retrofitting method for a full-body scanner for scanning an individual before access to a restricted access area, the method comprising:

• providing a shoe scanning system comprising a detection unit having:
• a main detector comprising at least one short-range sensing element and at least one long-range sensing element,
• a communication unit for transmitting a message to an indication unit, and
• a processing unit connected to the main detector by a data link for receiving data and controlling the communication unit for sending a detection signal when the main detector indicates a presence of metal and/or unauthorized object(s);
• wherein said at least one short-range sensing element and said at least one long-range sensing element are each placed on a flat planar board located under a planar walking surface of a path toward said area so as to sense the metal and/or unauthorized object(s) located above said surface, each of the at least one short-range sensing element having a first surface area and each of the at least one long-range sensing element having a second surface area larger than the first surface area to sense the metal and/or unauthorized object(s) located at different distances above said surface;
• establishing a data link between the communication unit of the detection unit and an indication unit for providing instructions to the individual and/or to an assistant, the indication unit being part either of the shoe scanning system or of the full-body scanner,
• wherein the method further comprises a step of selecting a detection threshold distance under which the metal and/or unauthorized object(s) is detected so as to allow a detection within a predefined detection volume of the full-body scanner, within an otherwise blind, oriented-blind and/or indiscriminating detection volume of the full-body scanner, wherein the blind detection volume is not otherwise detected, the oriented-blind detection volume lacks sensitivity to certain orientations of the metal and/or unauthorized object(s), and the indiscriminating detection volume is where the system is unable to discriminate the metal and/or unauthorized object(s) from non-metal and/or non-unauthorized object(s).