Double-sampling to improve signal-to-noise ratio (SNR) of dynamic spectrum (DS) in full spectral range

To balance the signal-to-noise ratio (SNR) of dynamic spectrum (DS) in the full spectral range due to the light intensity and the tissue absorption, we present a double-sampling method which is implemented by two spectral samplings at different integration times. In the first spectral sampling, we obtain a part of DS in the spectral range with high SNR. For the second, we increase the integration time to enhance the sensitivity of DS in original low SNR range. The combinative spectrum of two samplings is defined as the final DS for the continued model input variables. The experimental results demonstrated that the double-sampling method can widen the effective spectral range and significantly improve the SNR of DS.