Fig. 4: The homodyne signal level for different probe and noise power.

Red: probe light back-reflected from a rough glass surface mounted on the optical table, magenta: probe light back-reflected from the quadcopter with phase noise induced by mechanical vibration, black: noise light. The reference power is kept around 260 mW to maximize the conversion efficiency. The signal levels are measured relative to the shot noise level, with 100 ms integration time.