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physical phenomena > process > physical process > optical process > radiation modification > radiation direction modification

radiation direction modification
subject			fact

radiation direction modification	changes property direction
	is a kind of radiation modification
optical process	has domain optics

Kinds of radiation direction modification :

• diffraction (1 kind, 6 facts) - A property which distinguishes wave-like motions. When a wave is incident upon a barrier which is broken by a narrow slit (of comparable size to the wavelength), then the slit will act as a new isotopic source of secondary waves., The bending of light in passing a sharp edge or tiny aperture., A wave-like property of light which allows it to curl around obstacles whose size is about that of the wavelength of the light. The disturbed waves then interfere to produce ripple-patterns.
• dispersion (3 facts) - The separation of a beam of light into the individual wavelengths of which it is composed by means of refraction or diffraction., Resolution of white light into its component wavelengths, either by refraction or by diffraction.
• gravitational lensing (8 facts) (deflection of light) - Gravitational effect that bends a ray of light. Such an effect was predicted within the general theory of relativity, although previously considered impossible., The apparent path of a photon is altered from a straight line by the gravitational field of the Sun. The path is deflected radially away from the Sun by up to 1".75 at the Sun's limb. Correction for this effect, which is independent of wavelength, is included in the reduction from mean place to apparent place., The bending of the beam of light due to gravity. It is observable when the light from a star or planet passes a massive object such as the Sun., Deflection of electromagnetic radiation from a distant background source by a strong gravitational field associated with a foreground source resulting in more than one image of the original source. Many double-quasars are produced by this phenomenon., The effect of matter in curved spacetime, which tends to focus any beam of radiation from a distant source. In effect, the spacetime curvature is a lens of great focal length. At z ≈ 1, the angular size of an object starts increasing with distance., The bending of light caused by the gravity of an object lying between us and the light source. This may cause the light source to look brighter than it normally does.
• refraction (1 kind, 5 facts) - Deflection (or "bending") of light - or any ray as it passes from one medium into another of greater or lesser density, representing a change in overall speed of the ray. Refracting telescopes rely on the refraction of light through lenses. The refractive index of a medium (e.g., glass) is a measure of the medium's "bending" power.
• scattering (16 kinds, 44 facts) - Collision between a photon and a particle, The process whereby light is absorbed and reemitted in all directions, with essentially no change in frequency. Scattering by free electrons was the dominant source of opacity in the early universe.