What is a photocathode?
Q: What is a photocathode?
A: A photocathode is a negatively charged electrode in a light detection device.
Q: What is the main function of photomultipliers?
A: The main function of photomultipliers is to take a little light and make more of it.
Q: What are some examples of instruments that need to magnify the amount of light coming in?
A: Examples of instruments that need to magnify the amount of light coming in are astronomical telescopes and military night-sight equipment such as binoculars and telescopes on helmets and rifles.
Q: What happens when light strikes a layer of glass coated with a special light-sensitive metal?
A: When light strikes a layer of glass coated with a special light-sensitive metal, the absorbed energy causes electrons to jump off, which is called the 'photoelectric effect'.
Q: What are the freed electrons collected for in a light detection device?
A: The freed electrons are collected to produce the final image in a light detection device.
Q: What is the role of the lens in a telescope or binoculars?
A: The role of the lens in a telescope or binoculars is to pass the light onto a layer of glass coated with a special light-sensitive metal.
Q: What is the main type of photomultiplier?
A: The main type of photomultiplier is a photocathode.
