Definition

Noun: 1. An optical device: A Kerr cell is a specific type of optical device. It consists of a transparent container (cell) filled with a liquid or gas, placed between two polarizing filters. It has two electrodes to apply an electric field. Its function is to control light: it only allows light to pass through when the electric field causes the polarization planes of the light inside the cell to align correctly with the second polarizer. This property makes it useful as a very fast shutter or to modulate (vary the intensity of) a laser beam.

Usage Examples

• Noun:
  • The high-speed camera used a Kerr cell as its shutter to capture the rapid event.
  • To modulate the laser signal, the engineer passed it through a Kerr cell.
  • The experiment demonstrated the electro-optic effect using a simple Kerr cell filled with nitrobenzene.

Advanced Usage

• Kerr Effect: The operation of a Kerr cell is based on the Kerr effect (or quadratic electro-optic effect), where an applied electric field induces birefringence (double refraction) in an otherwise isotropic material, changing its optical properties.
  • The Kerr effect is exploited in the Kerr cell to rotate the polarization of light.

Variants and Related Words

• Electro-optic modulator: A broader category of devices that use an electric field to modulate light, which includes Kerr cells.
• Pockels cell: A similar electro-optic device that uses a different physical effect (the linear electro-optic effect) and typically uses crystalline materials instead of liquids.

Synonyms

• Optical shutter (when used specifically for that function)
• Light modulator (when used specifically for that function)

Related Phrases

• To modulate a beam: To vary the intensity, phase, or polarization of a light beam. This is a primary function of a Kerr cell.
  • The Kerr cell was used to modulate the beam for the communication experiment.

Noun

1. optical device consisting of a transparent cell with two electrodes between two polarizing media; passes light only if the two planes of polarization are parallel; used as a high-speed shutter or to modulate a laser beam