What is a photomultiplier tube?
Q: What is a photomultiplier tube?
A: A photomultiplier tube is a transducer that converts photons into electrons, which generate a current and voltage.
Q: What is the sensitivity of photomultiplier tubes?
A: Photomultiplier tubes have very high sensitivity and can detect low levels of incident light, even as low as a single photon.
Q: How does a photomultiplier convert photons into electrons?
A: When an incoming photon strikes the photocathode surface of the PMT, it emits electrons, which are then accelerated toward additional electrodes by a potential difference of about 90 volts.
Q: What happens when the electrons strike the electrodes in a photomultiplier?
A: Upon striking the electrodes, more electrons are emitted, and this process repeats nine times, each time generating more and more electrons. This process can generate 106 to 107 electrons for each individual photon.
Q: How are the generated electrons collected in a photomultiplier?
A: The generated electrons are collected at the anode where the current and voltage is then measured.
Q: How can the sensitivity of photomultipliers be improved?
A: The sensitivity of the photomultiplier can be improved by cooling it, to reduce temperature-induced noise.
Q: What are some common applications of photomultiplier tubes?
A: Photomultiplier tubes are commonly used for analysis techniques as well as medical and research purposes.
