Electro–optics is a branch of

electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...

electronic engineering Electronics engineering is a sub-discipline of electrical engineering which emerged in the early 20th century and is distinguished by the additional use of active components such as semiconductor devices to amplify and control electric current ...

, materials science, and material physics involving components, electronic devices such as

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The ...

laser diode The laser diode chip removed and placed on the eye of a needle for scale A laser diode (LD, also injection laser diode or ILD, or diode laser) is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with ...

s, LEDs,

waveguide A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities de ...

s, etc. which operate by the propagation and interaction of light with various tailored materials. It is closely related to the branch of

optics Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultrav ...

, involving application of generation of

photon A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they alwa ...

s, called

photonics Photonics is a branch of optics that involves the application of generation, detection, and manipulation of light in form of photons through emission, transmission, modulation, signal processing, switching, amplification, and sensing. Though ...

. It is not only concerned with the " electro–optic effect", since it deals with the interaction between the electromagnetic ( optical) and the

electrical Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described ...

( electronic) states of materials.

Electro-optical devices

The electro-optic effect is a change in the optical properties of an optically active material due to interaction with light. This interaction usually results in a change in the

birefringence Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. These optically anisotropic materials are said to be birefringent (or birefractive). The birefri ...

, and not simply the refractive index of the medium. In a

Kerr cell The Kerr effect, also called the quadratic electro-optic (QEO) effect, is a change in the refractive index of a material in response to an applied electric field. The Kerr effect is distinct from the Pockels effect in that the induced index chang ...

, the change in birefringence is proportional to the square of the optical electric field, and the material is usually a liquid. In a

Pockels cell The Pockels effect or Pockels electro-optic effect, named after Friedrich Carl Alwin Pockels (who studied the effect in 1893), changes or produces birefringence in an optical medium induced by an electric field. In the Pockels effect, also known as ...

, the change in birefringence varies linearly with the electric field, and the material is usually a crystal. Non-crystalline, solid electro-optical materials have generated interest because of their low cost of production. These organic, polymer-based materials are also known as organic EO material, plastic EO material, or polymer EO material. They consist of nonlinear optical chromophores in a polymer lattice. The nonlinear optical chromophores can produce Pockels effect.

References

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External links

Introduction to Electro-Optical Systems in Unmanned Vehicle Applications - Unmanned Systems Technology
{{Authority control Atomic, molecular, and optical physics Optoelectronics Nonlinear optics