Optical Radiation

Optical Radiation


light in the broad sense of the word, electromagnetic waves with wavelengths between 1 nanometer and 1 millimeter. Infrared radiation and ultraviolet radiation, as well as the visible radiation perceived by the human eye, are classified as optical radiation. The term “light” is close in meaning to “optical radiation” but historically has had less definite spectral boundaries—often not all optical radiation but just the visible band has been called light. The forming of directed radiation fluxes by means of optical systems incorporating such devices as lenses, mirrors, optical prisms, and diffraction gratings is characteristic of optical methods of research.

The wave properties of optical radiation are responsible for such phenomena as diffraction, interference, and polarization of light. A number of optical phenomena, however, cannot be understood unless optical radiation is conceived of as a flux of fast particles, or photons. This wave-particle duality of optical radiation connects it with other objects in the microworld and finds a general explanation in quantum mechanics. The speed of light, or the propagation velocity of optical radiation, in a vacuum is about 3 × 108 m/sec. In other mediums the speed of optical radiation is lower. The value of the refractive index of a medium is given by the ratio of the speeds in a vacuum and in the medium and is in general different for optical radiation of different wavelengths. The dispersion of optical radiation is a result of this fact.

The types of optical radiation are classified according to such features as origin (thermal radiation, luminescent radiation), homogeneity of spectral composition (monochromatic, polychromatic), orientation of electric and magnetic vectors (natural, linearly polarized, circularly polarized, elliptically polarized), and degree of diffuseness of the radiation flux (directional, diffuse, mixed).

The optical radiation flux incident on the surface of a body is partially reflected, partially transmitted through the body, and partially absorbed by the body. The absorbed part of the optical radiation energy is converted primarily into heat and increases the temperature of the body. Other types of conversion of the energy of optical radiation, however, are also possible. Examples are the photoelectric effect (photoelectric emission), photo-luminescence, and photochemical conversions.

For the role of optical radiation and optical methods of investigation in science and technology see and its bibliography,


References in periodicals archive ?
The photoionization laser will serve to create a positively charged particle from the neutral calcium atom in the two-stage photoionization process.Calcium ions will allow studying the properties of absorption and emission of optical radiation by spatially localized individual ions, improving the possibilities of controlling the degrees of freedom of captured ions and implementing applications in the field of scalable quantum communication with atoms and photons.
Lens material and lens colour contribute to the level of transmission and absorption of optical radiation. High levels of UV protection can be achieved with clear spectacle lenses.
Dr Richard Findlay, secretary of the Society for Radiological Protection's Electron Magnetic Field and Optical Radiation Committee, told the Manchester Evening News: "The mast will produce an electromagnetic field which is a form of radiation.
The optical radiation produced by all 16 transmitters is combined into a single optical flow using an optical combiner and sent through a 150 km long span of G.652.D standard single mode fiber (SMF).
An AGN, once it's formed, releases massive bursts of high-energy X-ray, ultraviolet and optical radiation.
Electrical field [22] and optical radiation [23] may also lead to formation of reversible aggregates.
The coherent optical radiation (at a wavelength near the fluorescence maximum wavelength) can be amplified upon the excited state population which can be obtained by one-end or side excitation condition.
To alter optical signals to electrical signals and to exploit optical radiation [4] photoconductors, phototransistors, laser diodes, photodiodes, electrooptic modulators, and other components are frequently employed in optoelectronic telecommunications systems.
On the other hand, optical radiation has its own scale -- the wavelength (in the visible range of the spectrum it is about 0.5 micrometers).
In the measurement of optical radiation water, repeatability of absorption spectra for a long period of ranges from 1%, and this value should be taken as the error measurement.
There are three ways to access these structures (transsylvian, subtemporal and transtemporal), each one with advantages and disadvantages related to the areas of language, cognitive processing and subcortical fibers, especially the optical radiation (1,3).
In this paper, the Cherenkov optical radiation in 3D metamaterials by a nonrelativistic modulated source having the own frequency [[omega].sub.0] with an emphasis on the dispersive properties of the medium is numerically studied.