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Glite Dictionary
photocathode

photocathode

9.9
A part in devices like night vision goggles that gives off electrons when light hits it
  • noun
  • /ˌfoʊtəˈkæθoʊd/
  • Specialized
translation icon : fotocátodo
  • In the laboratory, we connected the photocathode to a photomultiplier tube to measure light intensities.

Examples

  • The scientist explained that the photocathode emits electrons when light strikes its surface.

  • Spin-polarized electrons were created at the linac's upstream end by circularly polarized light hitting a specially developed gallium arsenide photocathode.

    Academic text (2005)

  • A photocathode is essential for converting light into an electrical signal in television cameras.

How Sensitive

PMT
  • Specialized
9.9
photocathode
  • Specialized
9.9
electrode
  • Specialized
45 5.1

Surface Forms

photocathode singular
photocathodes plural

Morphology

photocathode = cathode (semi-transparent) = photo + cathode

The word is built transparently from photo- 'light' plus cathode, but the full sense is a specialized technical term rather than an everyday meaning.

Etymology

Photocathode comes from two parts: photo meaning 'light', as in photograph, and cathode meaning 'way down' or 'descent'. So a photocathode is the electrode in a tube that reacts to light by releasing electrons to start an electrical signal.