Method and apparatus for identifying a substance using a spectral library database

Abstract

A spectroscopic detector for identifying the presence of a first substance in the presence of another substance includes a laser for illuminating the substances at a plurality of wavelengths to induce the emission of radiation characteristic of the substance; a spectrometer for measuring the emitted radiation to obtain a plurality of spectral measurement data; and a processor for processing the data. An algorithm combines the data into a composite spectrum and a parameter characteristic of the first substance is identified while information in the composite spectrum contributed by emission of radiation from the other substance is removed to identify the presence of the first substance and obtain a characteristic spectral signature of the first substance. The signature is compared to signatures in a spectral library database, wherein at least some of the library signatures have spectral characteristics differentiated from each other by identifiable spectral characteristics caused by environmental factors.

1 . A method of identifying the presence of a first substance in the presence of at least one other substance, comprising: 
 illuminating said first substance and said at least one other substance with electromagnetic radiation of one or more wavelengths to thereby induce the emission of radiation characteristic of the substances being illuminated;    measuring the emitted radiation to obtain a plurality of spectral measurement data; and    inputting said spectral measurement data into a processor, said processor including a processing algorithm configured for: 
 combining the plurality of spectral measurement data into a composite spectrum;  
 applying said algorithm to said composite spectrum whereby at least one parameter characteristic of said first substance is identified while information in said composite spectrum contributed by an emission of radiation from said at least one other substance is removed to thereby identify the presence of said first substance, and thereby obtaining a characteristic spectral signature of said first substance; and  
 comparing the spectral signature of said first substance to spectral signatures of substances in a spectral library database, wherein at least some of said library spectral signatures have spectral characteristics differentiated from each other by identifiable spectral characteristics caused by one or more environmental factors.  
   
   
   
       2 . A method as in  claim 1 , wherein the one or more environmental factors include a growth medium.  
   
   
       3 . A method as in  claim 1 , wherein the one or more environmental factors include a stage of development of a substance of interest.  
   
   
       4 . A method as in  claim 1 , wherein the one or more environmental factors include a stage of development of a substance not of interest.  
   
   
       5 . A method as in  claim 1 , wherein the plurality of spectral measurement data comprises multiple measurements of emitted radiation at a resolution lower than 0.1 cm −1 .  
   
   
       6 . A method as in  claim 1 , wherein the processing algorithm includes a multispectral data processing algorithm for analyzing multispectral data.  
   
   
       7 . A method as in  claim 1 , wherein the illuminating is with radiation in the ultraviolet wavelength range.  
   
   
       8 . A method of identifying the presence of a first substance in the presence of at least one other substance, comprising: 
 illuminating said first substance and said at least one other substance with electromagnetic radiation of one or more different wavelengths to thereby induce the emission of radiation characteristic of the substance being illuminated;    measuring the emitted radiation to obtain a plurality of spectral measurement data;    inputting said spectral measurement data into a processor, said processor including a multispectral data processing algorithm;    applying said algorithm to said plurality of spectral measurement data whereby at least one parameter characteristic of said first substance is identified while information contributed by an emission of radiation from said at least one other substance is removed to thereby identify the presence of said first substance, and thereby obtaining a characteristic spectral signature of said first substance; and    comparing the spectral signature of said first substance to spectral signatures of substances in a spectral library database, wherein at least some of said library spectral signatures have spectral characteristics differentiated from each other by identifiable spectral characteristics caused by one or more environmental factors.    
   
   
       9 . A method as in  claim 8 , wherein the one or more environmental factors include a growth medium.  
   
   
       10 . A method as in  claim 8 , wherein the one or more environmental factors include a stage of development of a substance of interest.  
   
   
       11 . A method as in  claim 8 , wherein the one or more environmental factors include a stage of development of a substance not of interest.  
   
   
       12 . An apparatus for identifying the presence of a first substance in the presence of at least one other substance, comprising: 
 means for illuminating said first substance and said at least one other substance with electromagnetic radiation at a plurality of wavelengths to thereby induce the emission of radiation characteristic of the substance;    means for measuring the emitted radiation at a plurality of emission wavelengths to obtain a plurality of spectral measurement data; and    a processor for processing said spectral measurement data, said processor including a multispectral data processing algorithm for (i) identifying at least one parameter characteristic of said first substance while removing information in said spectral data contributed by an emission of radiation from said at least one other substance to thereby identify the presence of said first substance, and thereby obtaining a characteristic spectral signature of said first substance, and (ii) comparing the spectral signature of said first substance to spectral signatures of substances in a spectral library database, wherein at least some of said library spectral signatures have spectral characteristics differentiated from each other by identifiable spectral characteristics caused by one or more environmental factors.    
   
   
       13 . An apparatus as in  claim 12 , wherein the one or more environmental factors include a growth medium.  
   
   
       14 . An apparatus as in  claim 12 , wherein the one or more environmental factors include a stage of development of a substance of interest.  
   
   
       15 . An apparatus as in  claim 12 , wherein the one or more environmental factors include a stage of development of a substance not of interest.  
   
   
       16 . An apparatus as in  claim 12 , wherein the illuminating is with radiation in the ultraviolet wavelength range.  
   
   
       17 . An apparatus for identifying the presence of a first substance in the presence of at least one other substance, comprising: 
 a laser for illuminating said first substance and said at least one other substance with electromagnetic radiation at a plurality of wavelengths to thereby induce the emission of radiation characteristic of the substance;    means for measuring the emitted radiation at a plurality of emission wavelengths to obtain a plurality of spectral measurement data; and    a processor for processing said spectral measurement data, said processor including a processing algorithm configured for: 
 combining the plurality of spectral measurement data into a composite spectrum;  
 applying said algorithm to said composite spectrum whereby at least one parameter characteristic of said first substance is identified while information in said composite spectrum contributed by an emission of radiation from said at least one other substance is removed to thereby identify the presence of said first substance, and thereby obtain a characteristic spectral signature of said first substance; and  
 comparing the spectral signature of said first substance to spectral signatures of substances in a spectral library database, wherein at least some of said library spectral signatures have spectral characteristics differentiated from each other by identifiable spectral characteristics caused by one or more environmental factors.  
   
   
   
       18 . An apparatus as in  claim 17 , wherein the one or more environmental factors include a growth medium.  
   
   
       19 . An apparatus as in  claim 17 , wherein the one or more environmental factors include a stage of development of a substance of interest.  
   
   
       20 . An apparatus as in  claim 17 , wherein the one or more environmental factors include a stage of development of a substance not of interest.  
   
   
       21 . An apparatus as in  claim 17 , wherein the plurality of spectral measurement data comprises multiple measurements of emitted radiation at a resolution of lower than 0.1 cm −1 .  
   
   
       22 . An apparatus as in  claim 17 , wherein the processing algorithm includes a multispectral data processing algorithm for generating multispectral data.  
   
   
       23 . An apparatus as in  claim 17 , wherein the illuminating is with radiation in the ultraviolet wavelength range.