US Patent 7471390 Spectrometer signal quality improvement via background subtraction

A spectrometer collects background spectra during the idle time in which it is not collecting spectra from a sample. These spectra are collected over a range of exposure times, allowing the background reading on each pixel to be modeled as a function of exposure time. When sample spectra are then collected, the exposure time for the sample spectra can be used with the modeled function to compute an estimated background within the sample spectra. The estimated background can then be subtracted from the sample spectra, thereby reducing the noise therein.