Method and apparatus for acquiring Raman spectra without background interferences

A method of generating a Raman spectrum which is substantially free of background interference comprising the steps of:

• a. providing a diode laser excitation means for irradiating a sample and generating an optical signal comprising a plurality of Raman wavelengths,
• b. providing a temperature controller means for setting the temperature of said diode laser excitation means,
• c. providing a dispersive spectrometer means for acquiring said optical signal where said dispersive spectrometer means comprises an optical dispersion means for dispersing said plurality of Raman wavelengths into a plurality of spatially resolved Raman wavelengths and said dispersive spectrometer means comprises a multi-element detector for simultaneously detecting said plurality of spatially resolved Raman wavelengths,
• d. providing a synchronization means for synchronizing said dispersive spectrometer means, said temperature controller means, and said diode laser excitation means,
• e. using said synchronization means to cause said temperature controller means to set the temperature of said diode laser excitation means to a plurality of temperatures comprising a number of predetermined temperatures where said number is greater than two,
• f. using said synchronization means to cause said diode laser excitation means to irradiate said sample when said diode laser excitation means is at said predetermined temperatures,
• g. acquiring a plurality of Raman spectra using said synchronization means to cause said dispersive spectrometer means to acquire at least one spectrum while said diode laser excitation means is at each of said predetermined temperatures and while said diode laser excitation means irradiates said sample,
• h. providing a computation means,
• i. processing said plurality of Raman spectra using said computational means to generate said Raman spectrum
• whereby said Raman spectrum is substantially lacking background-interference.

A method of generating a Raman spectrum which is substantially free of background interference comprising the steps of:

• a. providing a dispersive Raman spectrometer to acquire Raman spectra where said dispersive Raman spectrometer comprises an excitation source which can be adjusted to a predetermined excitation wavelength and used to generate a Raman spectrum from a sample,
• b. acquiring a group comprising at least three Raman spectra using said dispersive Raman spectrometer where each of the said Raman spectra is acquired at a substantially different excitation wavelength and where the difference in energy between any of said excitation wavelengths is substantially equal to a positive non-zero integer value times the smallest separation in energy of said excitation wavelengths,
• c. providing a computational means
• d. computing a Raman estimate means from said group using said computational means,
• e. computing a non-Raman estimate means from said group using said computational means,
• f. computing a Raman spectrum from said Raman estimate means, said non-Raman estimate means, and said group using said computational means and an algorithm means,
• whereby said Raman spectrum is generated substantially free of background interference.