Charge-coupled devices (CCDs)

Definition

Charge-coupled devices (CCDs) are semiconductor devices used to convert optical light into electronic signals. They are commonly used in astronomy for capturing high-resolution images of celestial objects.

5 Must Know Facts For Your Next Test

1. CCDs consist of an array of light-sensitive cells called pixels that detect photons.
2. They offer high quantum efficiency, meaning they can convert a large portion of incoming photons into electrical signals.
3. CCDs have low noise levels, which is crucial for capturing faint astronomical objects.
4. They require cooling to reduce thermal noise, often achieved with liquid nitrogen or Peltier coolers.
5. CCDs are integral components in both professional telescopes and space observatories like the Hubble Space Telescope.

Review Questions

Related terms

Photodiode: A semiconductor device that converts light into an electrical current, commonly used in light detection applications.

Quantum Efficiency:

The effectiveness with which a photon detector converts incident photons into electrons, critical for measuring CCD performance.

Thermal Noise:

Random fluctuations in an electrical signal caused by the thermal agitation of electrons, which can affect the sensitivity of CCDs.