Another possibility, raised in an essay by the Swedish fantasy writer and editor Rickard Berghorn, is that the name Alhazred was influenced by references to two historical authors whose names were Latinized as Alhazen: Alhazen ben Josef, who translated Ptolemy into Arabic ; and Abu ' Ali al-Hasan ibn al-Haytham, who wrote about optics, mathematics and physics.

In physics and optics, the Abbe number, also known as the V-number or constringence of a transparent material, is a measure of the material's dispersion ( variation of refractive index with wavelength ) in relation to the refractive index, with high values of V indicating low dispersion ( low chromatic aberration ).

An optical aberration is a departure of the performance of an optical system from the predictions of paraxial optics.

While " distortion " can include arbitrary deformation of an image, the most pronounced modes of distortion produced by conventional imaging optics is " barrel distortion ", in which the center of the image is magnified more than the perimeter ( figure 7a ).

Minsk has a digital metropolitan network ; waiting lists for telephones are long ; fixed line penetration is improving although rural areas continue to be undeserved ; intercity-Belarus has developed fibre-optic backbone system presently serving at least 13 major cities ( 1998 ); Belarus's fibre optics form synchronous digital hierarchy rings through other countries ' systems ; an inadequate analogue system remains operational.

In radio communications, for example, bandwidth is the frequency range occupied by a modulated carrier wave, whereas in optics it is the width of an individual spectral line or the entire spectral range.

Laser spectroscopy is used as a tool for studying phenomena with energy in the range of visible light, for example, to study non-linear optics and forbidden transitions in media.

Rendering is practically exclusively concerned with the particle aspect of light physics — known as geometric optics.

In optics, particularly as it relates to film and photography, depth of field ( DOF ) is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image.

Huygens ' principle when applied to an aperture simply says that the far-field diffraction pattern is the spatial Fourier transform of the aperture shape, and this is a direct by-product of using the parallel-rays approximation, which is identical to doing a plane wave decomposition of the aperture plane fields ( see Fourier optics ).

where λ is the wavelength of the light and N is the f-number ( focal length divided by diameter ) of the imaging optics.

Although modern quantum optics tells us that there also is a semi-classical explanation of the photoelectric effect — the emission of electrons from metallic surfaces subjected to electromagnetic radiation — the photon was historically ( although not strictly necessarily ) used to explain certain observations.

It also gives rise to quantum optics, which is different from quantum electrodynamics in that the matter itself is modelled using quantum mechanics rather than quantum field theory.

In physics and engineering disciplines, such as optics, acoustics, and radio, frequency is usually denoted by a Latin letter f or by a Greek letter ν ( nu ).

Sometimes it is referred to as " fly-by-light " due to its use of fiber optics.

He also extended his study of optics to the human eye, and is generally considered by neuroscientists to be the first to recognize that images are projected inverted and reversed by the eye's lens onto the retina.

" Today, Astronomiae Pars Optica is generally recognized as the foundation of modern optics ( though the law of refraction is conspicuously absent ).

* In crystal optics, lambda is used to represent the period of a lattice.

The probability ( shown as the colour opacity ( optics ) | opacity ) of finding the particle at a given point x is spread out like a waveform, there is no definite position of the particle.

During this period ( 1664 – 1666 ) he created the basis of calculus, and performed the first experiments in the optics of colour.

* Hermann von Helmholtz, great German polymath, invented the ophthalmoscope ( 1851 ) and published important work on physiological optics, including colour vision ( 1850s ).

The probability ( shown as the colour opacity ( optics ) | opacity ) of finding the particle at a given point x is spread out like a waveform, there is no definite position of the particle.

One dimensional photonic crystals are already in widespread use in the form of thin-film optics with applications ranging from low and high reflection coatings on lenses and mirrors to colour changing paints and inks.

These pixel components, sometimes called subpixels, appear as a single colour to the human eye because of blurring by the optics and spatial integration by nerve cells in the eye.

The probability ( shown as the colour opacity ( optics ) | opacity ) of finding the particle at a given point x is spread out like a waveform, there is no definite position of the particle.

Science, optics and you.

# The distribution of atmospheric seeing through the atmosphere ( the C < sub > N </ sub >< sup > 2 </ sup > profile described below ) causes the image quality in adaptive optics systems to degrade the further you look from the location of reference star

The solution to this dilemma was not of particular importance to Kepler as he did not see it as pertaining to optics, although he did suggest that the image was later corrected " in the hollows of the brain " due to the " activity of the Soul.

Moreover, various phenomena occur in the world even though Maxwell's equations predicts them to be impossible, such as " nonclassical light " and quantum entanglement of electromagnetic fields ( see quantum optics ).

Various specialized properties of molecular crystals and organic polymers with conjugated systems are of interest depending on applications, e. g. thermo-mechanical and electro-mechanical such as piezoelectricity, electrical conductivity ( see conductive polymers and organic semiconductors ), and electro-optical ( e. g. non-linear optics ) properties.

There exist other physical processes that can lead to a shift in the frequency of electromagnetic radiation, including scattering and optical effects ; however, the resulting changes are distinguishable from true redshift and not generally referred as such ( see section on physical optics and radiative transfer ).

In fiber optics and telecommunications, an index-matching material may be used in conjunction with pairs of mated connectors, with mechanical splices, or at the ends of fibers ( see: Optical fiber connector ).

A less familiar example of speckle is the highly magnified image of a star through imperfect optics or through the atmosphere ( see speckle imaging ).

* Plano-convex lenses, in optics ; see Lens ( optics )# Types_of_simple_lenses

If red, blue, and green light ( the additive primaries ) are mixed, the result is something close to white light ( see Prism ( optics )).

The same analysis is also used in accelerator physics to track particles trough the magnet installations of a particle accelerator, see Beam optics.

* Negative lenses, uses to describe diverging optics, see lens ( optics )

In this generation of telescopes, the mirror is usually very thin, and is kept in an optimal shape by an array of actuators ( see active optics ).

Concepts of Fourier optics are used to reconstruct the phase of light intensity in the spatial frequency plane ( see adaptive-additive algorithm ).

* inelastic collisions between electromagnetic waves and the transmitting medium ( Brillouin scattering and Raman scattering ), important in fiber optics, see below ;

We also note that a perfect point source radiator will not only radiate a uniform spectrum of propagating plane waves, but a uniform spectrum of exponentially decaying ( evanescent ) waves as well, and it is these which are responsible for resolution finer than one wavelength ( see Fourier optics ).

It can be shown ( see Fourier optics, Huygens-Fresnel principle, Fraunhofer diffraction ) that the field radiated by a planar object ( or, by reciprocity, the field converging onto a planar image ) is related to its corresponding source ( or image ) plane distribution via a Fourier transform ( FT ) relation.

* James Orin Incandenza, Jr., an optics expert and filmmaker ( see " Filmography " entries below in " External Links "), is the founder of the Enfield Tennis Academy.

For in-depth informations behind the laws of optics regarding the influence that focal length and different formats have on field sizes, see 35 mm equivalent focal length, crop factor, image sensor format, and Digital photography: Sensor size and angle of view.

It also used to contain direct-view optics ( DVO ) which the copilot / gunner ( CPG ) could see through the Optical Relay Tube ( ORT ).

For light scattering, see: category: Scattering, absorption and radiative transfer ( optics )

It is useful in the manufacture of optics ( for reflective, anti-reflective coatings or self-cleaning glass, for instance ), electronics ( layers of insulators, semiconductors, and conductors form integrated circuits ), packaging ( i. e., aluminium-coated PET film ), and in contemporary art ( see the work of Larry Bell ).

As long as the superposition principle holds ( which is often but not always ; see nonlinear optics ), the behavior of any light wave can be understood as a superposition of the behavior of these simpler plane waves.