Spectrometer SNR Estimator
Estimate signal-to-noise ratio for array spectrometers, showing individual noise contributions and dominant noise source.
Signal-to-noise ratio in an array spectrometer is determined by three noise sources that add in quadrature: shot noise from the signal (√signal, Poisson), dark noise from thermally generated electrons (√(D · t · n_pix)), and read noise from the detector amplifier (σᵣ · √n_pix). This estimator takes a photon signal rate, integration time, quantum efficiency, dark current per pixel, read noise, number of binned pixels, and number of averaged scans, then returns the signal electron count, each noise component, total noise, and final SNR. Scan averaging improves SNR as √N_scans, as read and dark noise contributions are reduced relative to the accumulated signal. The tool also identifies the dominant noise source, which indicates whether longer integration, cooling, or a lower-noise detector is the most effective improvement path.