Body capable of absorbing energy of all wavelengths falling on it; it is also capable of radiating all frequencies in a particular ratio to its absorbing properties. The value of the ratio depends only on the temperature of the body.

A hypothetical perfect radiator, which absorbs and re-emits all radiation incident upon it.

In radiation physics, an ideal blackbody is a theoretical object that absorbs all the radiant energy falling upon it and emits it in the form of thermal radiation. Planck's radiation law gives the power radiated by a unit area of blackbody, and the Stefan-Boltzman law expresses the total power radiated.

a body which absorbs all radiation and emits according to its temperature.

An ideal emitter which radiates energy at the maximum possible rate per unit area at each wavelength for any given temperature. According to Kirchoff's Law, a blackbody also absorbs all the radiant energy incident on it; i.e., no energy is reflected or transmitted.

A theoretically perfect absorber of all incident radiation.

An object which emits the maximum amount of energy that is theoretically possible at the given temperature.

a hypothetical object capable of absorbing all the electromagnetic radiation falling on it; "a black body maintained at a constant temperature is a full radiator at that temperature because the radiation reaching and leaving it must be in equilibrium"

a body that absorbs all the radiation that falls onto it

a body that does not reflect any of the light that falls on it

a body which absorbs all of the incident radiation and emits the maximum amount of radiation possible at its given temperature

a hypothetical body that absorbs all electromagnetic radiation falling on it and reflects none whatsoever

a hypothetical ideal body or surface that absorbs and reemits all radiant energy falling on it

a hypothetical object that absorbs all incoming thermal energy, but with none of that energy reflected or transmitted

a hypothetical object that absorbs all radiation falling on it

a hypothetical object that completely absorbs all of the radiation that hits it, and reflects nothing

a hypothetical perfect emitter and absorber of thermal radiant energy

an ideal absorber of radiation

an ideal object that absorbs all the radiation it receives

an ideal substance with a perfectly black surface that absorbs all the radiation that falls on it and emits radiation in specific ways dependent on temperature

an object that absorbs all the energy that falls upon it and, because it reflects no light, it would appear black to an observer

an object that completely absorbs all heat radiation, reaches temperature equilibrium and next radiates the absorbed heat again

an object that reflects no light (in terms of reflected light its black, hence the name) although it will still emit light

an object which absorbs all incident light-- neither reflecting it nor allowing it to pass through

an object which is a perfect absorber (absorbs at all wavelengths) and a perfect emitter (emits at all wavelengths) and does not reflect any light from its surface

a perfect absorber and emitter of radiation

a perfect object that does not reflect any light and absorbs all radiation)

a perfect source of both radiant energy emission and absorbtion

an object that is an ideal radiator when hot and a perfect absorber when cool. It absorbs radiation that falls upon it, reflecting no light: hence it appears to be black. Stars are considered blackbodies. The radiation emitted by blackbodies obey several simple laws (Wien's Law, The Stefan-Boltzmann Law).

an ideal material that absorbs all radiant energy incident upon it and emits radiant energy at the maximum possible rate per unit area at each wavelength for any given temperature. A blackbody has unit emissivity (emissivity of 1.0 across the entire spectrum).

A hot body with an incandescent black surface at a certain temperature used as a standard for comparison. Note that a black surface is the best radiator possible. A tungsten filament will emit slightly less radiation than a blackbody at the same temperature.

An ideal thermal radiator, normally used as a testing standard. The most common can be set to a specific temperature as the device emits almost 100% of the infrared radiation expected at a given temperature. Emissivity ratings are essentially a percentage value, compared to the blackbody. (Emissivity = 1.0, Reflectance = 0.0, Transmittance = 0.0)

an ideal body or surface that completely absorbs all radiant energy of any wavelength falling upon it with no reflection of energy.

A perfect radiator and absorber of electromagnetic energy. A blackbody has an emissivity of 1, and its NOAA IR channel temperature will be equivalent to its actual temperature.

an object that absorbs all incident radiation regardless of spectral or directional composition. A black body will also radiate energy at a rate expressed by the Stefan-Boltzmann Law with a spectral distribution expressed by Planck's radiation equation.

The ideal object whose absorptivity and emissivity (q.v.) are perfect and taken as unity.

A temperature radiator of uniform temperature whose radiant exitance in all parts of the spectrum is maximum obtainable from any temperature radiator of the same temperature. Correlated color temperature (CCT) correlates with the apparent color of a blackbody radiator at a given temperature.

An ideal substance that absorbs all radiation falling on it, and reflecting nothing.

The perfect absorber of all radiant energy that strikes it. The blackbody is also a perfect emitter Therefore, both its absorbance (A) and emissivity (E) are unity. The blackbody radiates energy in predictable spectral distributions and intensities which are a function of the blackbody's absolute temperature.

An ideal body that completely absorbs all radiant energy striking it and, therefore, appears perfectly black at all wavelengths. The radiation emitted by such a body when heated is referred to as blackbody radiation. A perfect blackbody has an emissive of unity.

Radiation source, emittance=absorptance=1, reflectance=0

an object with a constant temperature that absorbs all radiation that hits it.

A hypothetical "body" that absorbs all of the electromagnetic radiation striking it - it does not reflect or transmit any of the incident radiation. The radiation emitted is consistent with Planck's law. In accordance with Kirchhoff's law, a blackbody not only absorbs all wavelengths, but emits at all wavelengths with the maximum possible intensity for any given temperature. Contrast with whitebody and graybody.

A substance that radiates energy at the maximum possible rate per unit area at each wavelength for any given temperature. A blackbody also absorbs all energy that falls on it.

A theoretical object that radiates the maximum amount of energy at a given temperature, and absorbs all the energy incident upon it. A blackbody is not necessarily black. (The name blackbody was chosen because the color black is defined as the total absorption of light energy.)

The ideal, perfect emitter and absorber of thermal radiation. It emits radiant energy at each wavelength at the maximum rate possible as a consequence of its temperature, and absorbs all incident radiance.

An object that is a perfect emitter and absorber of radiation.

A body with a surface emissivity of 1. Such a body will emit all of the thermal radiation it can (as described by theory), and will absorb 100% of the thermal radiation striking it. Most physical objects have surface emissivities less than 1 and hence do not have blackbody surface properties.

A body that absorbs all of the electromagnetic radiation striking it regardless of wavelength.

a perfect emitter and absorber of radiation. A blackbody emits radiation with a blackbody spectrum described by the Planck function (see PHY104) whose properties depend only on the body's temperature. Stars are approximately but not exactly blackbodies.

An ideal thermal radiator, usually one whose temperature can be controlled, radiating and absorbing the maximum possible thermal radiation for the set temperature. (Emissivity = 1.0, Reflectance = 0.0, Transmittance = 0.0)

A theoretical body used by the lighting industry as a standard for establishing the "color" and spectral qualities of lamps. A perfect blackbody, when its temperature has risen to 3500K would give out light of a certain color; at 4500K it would give a whiter color, and at 5500K a still whiter color.

A hypothetical body that cannot be excited to radiate by an external source of electromagnetic radiation of any frequency, direction, or state of polarization except in a negligibly small set of directions around that of the source radiation. The traditional definition of a blackbody - as one that absorbs all the radiation incident on it - is inadequate unless to this definition is added the requirement that the body be large compared with the wavelength of the incident radiation. The concept of radiation incident on a body is from geometrical (or ray) optics, which is never strictly valid (because all bodies are finite) and may break down completely when the body is small compared with the wavelength. This was recognized by Planck, but by almost no one who followed him. Although no strict blackbody exists, some bodies are approximately black over a limited range of frequencies, directions, and polarization states of the exciting radiation. See blackbody radiation, Planck's radiation law, emissivity. Planck, M., 1959: The Theory of Heat Radiation, p. 2.