1 February 1996 Noise measurements of a phase fluorometric instrument
Author Affiliations +
We present noise measurements of a phase fluorometric oxygen sensor that sets the limits of accuracy for this instrument. We analyze the phase sensitive detection measurement system with the signal ‘‘shot’’ noise being the only significant contribution to the system noise. Based on the modulated optical power received by the photomultiplier, the analysis predicts a noise spectral power density that was within 3 dB of the measured power spectral noise density. Our results demonstrate that at a received optical power of 20 fW the noise level was low enough to permit the detection of a change oxygen concentration of 1% at the sensor. We also present noise measurements of a new low-cost version of this instrument that uses a photodiode instead of a photomultiplier. These measurements show that the noise for this instrument was limited by noise generated in the preamplifier following the photodiode.
Raja Holavanahalli, Gary M. Carter, Shabbir B. Bambot, Vadde Venkatesh, Vivek Srinivas, "Noise measurements of a phase fluorometric instrument," Optical Engineering 35(2), (1 February 1996). https://doi.org/10.1117/1.601024 . Submission:

Back to Top