The Signal-to-Noise Ratio (SNR) is an important quantitative parameter for evaluating the capability of spectrometers.
The noises of CMOS image sensor, stray light and radiometric distortion play important roles in the spectrometer's SNR
performance. An Offner imaging spectrometer is designed and tested. By measuring the spectrometer's spectral response,
its SNR is calculated by the traditional statistical method and the wavelet analysis. Both methods give similar result and
can provide useful information during the spectrometer commissioning as well as performance evaluation.