Hamamatsu R1332 PMT Quantum Efficiency Measurement
The same procedure as described here was used. However, an integrating sphere was added between the monochromator output and the PMT or photodiode so as to uniformly distribute light over the detector surfaces. Thus, area corrections can be added to Equation 1 here, and it becomes
(1),
where λ is in nm, IPMT is the PMT anode photocurrent in Amps, GPMT is the gain of the PMT at a particular bias, Pphotodiode is the light source's power as measured by the photodiode in Watts, the photodiode detector area Aphotodiode is 1cm2, and the PMT area APMT is 20.27cm2
| Figure 1: QE spectrum at 1700V |
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| Figure 2: QE spectrum at 1800V |
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https://www.bnl.gov/muong-2/papers/PC_NIM_960411.pdf
This is the only source I have come across which mentions the quantum efficiency of our Hamamatsu R1332 tube. It notes on page 5 that the quantum efficiency of the tube is about 10% at 500nm, consistent with data shown above.