Extended Data Fig. 8. Comparison of the spectrometer with light modulation from a mechanical chopper or modulation from mirror vibration.
The modulation with a vibration mirror gives a slightly larger photo signal, however, it strongly depends on the mirror vibration amplitude in respect to the wavelength of the stationary wave. While light modulation with a mechanical 50/50 chopper does remove 50% of the light intensity, it is still present and adds to the photo signal in case of mirror modulation. A fast Fourier transformation of both signals results in the same signal position and comparable noisy background when normalized.