Detection of distant substances

Abstract

Disclosed are embodiments of methods and apparatus related to detection of substance(s) at a distance. For example, an apparatus can have a mount structure and an emitter mounted to the mount structure and configured to be trained on a target. The emitter can have a source configured to emit radiation and a mirror configured to direct the radiation toward the target. The apparatus can also have a collector mounted to the mount structure and configured to be trained on the target at the same time the emitter is trained on the target and concentrate collected radiation on a sensor. The apparatus can also have a detection system comprising the sensor and an interferometer configured to produce an interferogram. The processor can be configured to perform a Fourier transform on the interferogram to produce a spectrogram and analyze the spectrogram to determine presence or absence of known substances in or around the target.

1 . A rotating, scanning apparatus for distant detection of substances in an angular range, the apparatus comprising:
 a mount structure;   an emitter mounted to the mount structure and configured to illuminate a target located at an unknown distance from the emitter;   a collector mounted to the mount structure and configured to collect radiation from the direction of the illuminated target, the collected radiation comprising radiation emitted from the target as may be modified by interactions with any vapor on or near the target;   a detection system mounted to the mount structure comprising a sensor and a processor, the sensor configured to measure the collected radiation and the processor configured to detect, at or near real time, the presence or absence of a substance or plurality of substances in or around the target based, at least in part, on the collected radiation measured by the sensor;   where the mount structure has a rotating portion configured to rotate at least the emitter and the collector to sweep through an angular range such that the processor may, continuously and in substantially real time, determine the presence or absence of a substance or plurality of substances in or around a plurality of targets located at different angles from the apparatus within the angular range.   
     
     
         2 . The apparatus of  claim 1 , wherein the rotating portion is configured to rotate at least 360 degrees. 
     
     
         3 . The apparatus of  claim 1 , wherein the processor comprises multiple computers. 
     
     
         4 . The apparatus of  claim 1 , wherein the emitter and collector are configured to address targets at least 10 yards away. 
     
     
         5 . The apparatus of  claim 1 , wherein the emitter and collector are configured to address targets at least 100 yards away. 
     
     
         6 . The apparatus of  claim 1 , wherein the target comprises an illuminated portion of the angular range, and wherein the collector and detection system are configured to scan at a rate of at least 10 Hz, where each cycle comprises determining the presence or absence of a substance or plurality of substances in or around the target. 
     
     
         7 . The apparatus of  claim 6 , wherein the collector and detection system are configured to scan at a rate of at least 100 Hz, where each cycle comprises determining the presence or absence of a substance or plurality of substances in or around the target. 
     
     
         8 . The apparatus of  claim 6 , wherein the collector and detection system are configured to scan at a rate of at least 1,000 Hz, where each cycle comprises determining the presence or absence of a substance or plurality of substances in or around the target. 
     
     
         9 . The apparatus of  claim 6 , wherein the collector and detection system are configured to scan at a rate of at least 10,000 Hz, where each cycle comprises determining the presence or absence of a substance or plurality of substances in or around the target. 
     
     
         10 . The apparatus of  claim 1 , wherein the processor is configured to determine the presence or absence of a substance or plurality of substances in substantially real time by conveying to a user presence or absence of a substance or plurality of substances within  10  seconds or less of collecting radiation from the direction of the illuminated target. 
     
     
         11 . The apparatus of  claim 1 , wherein the processor is configured to determine the presence or absence of a substance or plurality of substances in substantially real time by conveying to a user presence or absence of a substance or plurality of substances within  1  second or less of collecting radiation from the direction of the illuminated target. 
     
     
         12 . The apparatus of  claim 1 , wherein the processor is configured to determine the presence or absence of a substance or plurality of substances in substantially real time by conveying to a user presence or absence of a substance or plurality of substances within 0.1 seconds or less of collecting radiation from the direction of the illuminated target. 
     
     
         13 . The apparatus of  claim 10 , wherein the apparatus is further configured to correlate the angle at which the presence or absence of a substance or plurality of substances was measured, thereby enabling a user to determine the angular direction of a potential threat. 
     
     
         14 . The apparatus of  claim 13 , wherein the apparatus is further configured to indicate the approximate distance from the apparatus to the target that resulted in information regarding the presence or absence of a substance or plurality of substances, thereby enabling a user to determine the distance to a potential threat. 
     
     
         15 . The apparatus of  claim 1 , further comprising a user interface configured to display information about the detected substance. 
     
     
         16 . The apparatus of  claim 1 , wherein the emitter has a power of more than 100 watts. 
     
     
         17 . The apparatus of  claim 16 , wherein the emitter has a power in the range of about 100 watts to about 1000 watts. 
     
     
         18 . The apparatus of  claim 1 , wherein the substance or plurality of substances may include one or more molecules related to explosives. 
     
     
         19 . The apparatus of  claim 18 , wherein the one or more molecules related to explosives may include one or more of TNT, RDX, DNT, HMX, plastic explosives, SEMTEX, nitroglycerine, and TAP. 
     
     
         20 . The apparatus of  claim 1 , wherein the angular range is at least 90 degrees. 
     
     
         21 . The apparatus of  claim 1 , wherein the angular range is at least 180 degrees. 
     
     
         22 . The apparatus of  claim 1 , wherein the angular range is about 360 degrees. 
     
     
         23 . The apparatus of  claim 1 , wherein the emitter illuminated the target with a collimated pencil-beam of electromagnetic radiation. 
     
     
         24 . The apparatus of  claim 23 , wherein the collimated pencil-beam of electromagnetic radiation comprises infrared electromagnetic radiation. 
     
     
         25 . A safety and alert system for detecting one or more distant volatile substances and informing a user, the system comprising:
 a rotating infrared radiator configured to sweep a beam of directional infrared radiation through a relevant angle to scan the horizon for targets, the horizon located at a distance of at least 10 yards from the safety and alert system;   a rotating radiation collector configured to also sweep its field of view through the same relevant angle of the rotating infrared radiator, collecting radiation from potential targets illuminated thereby;   a detector and processor configured to receive the radiation from the collector and spectroscopically determine the presence or absence of one or more volatile substances at or near the target based at least on comparison of results from the collected radiation with a library of data from known volatile substances; and   a warning interface configured to receive information from the processor and alert the user to the presence of one or more volatile substances.   
     
     
         26 . The system of  claim 25 , wherein the warning interface is further configured to indicate the approximate location of the one or more volatile substances. 
     
     
         27 . The system of  claim 25 , wherein the processor is configured to spectroscopically determine the presence or absence of one or more volatile substances using a Fourier transform of a spectral signature. 
     
     
         28 . The system of  claim 27 , wherein the library of data includes information from Fourier transforms of spectral signatures of known volatile substances. 
     
     
         29 . The system of  claim 25 , wherein the library of data from known volatile substances includes results from one or more explosive accelerants. 
     
     
         30 . The system of  claim 25 , wherein the processor comprises a Fourier transform infrared spectrometer. 
     
     
         31 . The system of  claim 25 , wherein the rotating radiation collector comprises a parabolic mirror configured to focus collected radiation on the sensor. 
     
     
         32 . The system of  claim 25 , wherein the infrared radiator is a substantially collimated infrared searchlight with an output power of at least 100 watts. 
     
     
         33 . A method of detecting distant volatile substances within an angular range, the method comprising:
 rotating an infrared illuminator to sweep a beam of directional infrared radiation through an angular range to scan the horizon for targets, the horizon located at a distance of at least 10 yards from the infrared illuminator;   rotating a radiation collector capable of collecting radiation from an illuminated target within the angular range;   synchronizing the rotations of the infrared illuminator and the radiation collector such that the radiation collector will sweep its field of view through the same angular range as the infrared illuminator, and will collect radiation emitted from the illuminated target as may be modified by interactions with any vapor on or near the target;   sensing the collected radiation from the radiation collector;   analyzing, in substantially real time, the collected radiation from the radiation collector to spectroscopically determine the presence or absence of one or more volatile substances at or near the target based at least on comparison of results from the collected radiation with a library of data from known volatile substances; and   alerting a user of the presence of one or more volatile substances at or near the target.