Terminological information
Time:11.04.2021Reading times:749
Absorbance
Compared with the light transmitted through the medium, the index of the light or ultraviolet absorbed by the medium is the logarithm of the ratio of the incident spectral irradiance to the transmitted spectral irradiance, which is a non unit number. Absorbance means monochromatic radiation, although it is sometimes used as an average applied over a specific wavelength range.
Source: RadTech
Absorptivity (absorption coefficient)
Absorbance of medium per unit thickness.
Source: RadTech
Actinometer
A chemical system or physical device used to determine the number of photons in a beam as a whole or per unit time. For example, the solution of ferric oxalate (III) can be used as a chemical light energy meter, while the radiant heat meter, thermopile and photodiode are devices whose electrical response can be related to the number of photons detected.
Source: RadTech
Actinometry
Determine the number of photons in the beam per unit time or integral with time.
Source: RadTech
Additive lamps
A small amount of metal halide is added into the mercury in the medium pressure mercury vapor ultraviolet lamp (arc lamp or microwave lamp). In addition to mercury emissions, these materials emit their characteristic wavelengths. [the term takes precedence over doped lamps].
Source: RadTech
Dichroic dichroic
In the range of two different wavelengths, it shows obviously different reflection or transmission. The dichroic reflector with low reflectance for long wavelength (IR) is called "cold mirror", while the reflector with strong reflectance for long wavelength is called "hot mirror".
Source: RadTech
Diffuse
A feature of a surface that reflects or scatters light or ultraviolet light uniformly in all directions (often confused with diffuse reflection).
Source: RadTech
Doped lamps
This term applies to UV lamps having a metal halide additive of mercury to change the emission spectrum of the lamp. (the term has been widely used by UV arc lamp manufacturers. In fact, this is an inaccurate statement, because the added chemical does not change the properties of another chemical). [the preferred term is additive lamp].
Source: RadTech
Dose of dose
Energy absorbed per unit mass. The precise definition of terms in EB curing and ionizing radiation technology: 1 Gy = 1 J / kg. Different materials receiving the same exposure may not absorb the same amount of energy. In EB, each unit of Gy replaces the previously used mrad unit (10 kGy = 1 mrad). Since most EB curable materials have a density of about 1g / cc, the dose is usually expressed as J / g or J / cm3. In UV curing, the term is usually used instead of the preferred term, effective energy density or exposure.
Dynamic exposure
Exposure to varying irradiance, such as when a lamp passes through a surface, or when the surface passes through a lamp or under a lamp. In this case, the energy is the time integral of the irradiance distribution.
Source: RadTech
Dynamic range
The span between the minimum irradiance and the maximum irradiance to which the radiometer accurately responds. Expressed as a ratio or in units of measurement (e.g. w / cm 2).
Source: RadTech
Effective energy density
Radiation energy in the specified wavelength range reaches the surface per unit area, usually expressed in Joule / cm2 or MJ / cm2. In the specified wavelength range (there is no wavelength specification, it is basically meaningless). Generally accepted abbreviations are w λ or e λ. [another term is exposure. ]
Source: RadTech
Effective irradiance
The radiation power reaching the surface per unit area in the specified wavelength range. It is expressed in watts or milliwatts per square centimeter (w / cm 2 or MW / cm 2) in a specific wavelength range (no wavelength specification, basically meaningless). For brevity, the term is shortened to irradiance when the wavelength range is clearly understood. Generally accepted abbreviations are e λ or I λ. Compared with spectral irradiance.
Source: RadTech
Einstein
One mole of photons. Sometimes equal to the energy of a mole of photons, but the use of such photons is not encouraged.
Source: RadTech
Electromagnetic spectrum
An extremely wide range of radiation that travels at the speed of light, characterized by wavelength, extending from radio waves (~ 104 m), visible light and ultraviolet light (~ 10-4 m) to gamma rays (~ 10-14 m).
Source: RadTech
Emission spectrum
The radiation from atoms or excitons is usually expressed as the power versus wavelength. The emission spectrum is unique for each atom or molecule. Spectra can be observed as narrow line emission (as in atomic emission spectra) or as quasi continuous emission (as in molecular emission spectra). Mercury plasma can emit line spectrum and continuous spectrum at the same time.
Source: RadTech
Energy density
The radiant energy reaching the surface per unit area is usually expressed in joules or MJ / cm 2. It's the time integral of irradiance.
It's the same as exposure. For parallel and perpendicular incident beams, they are not scattered or reflected, and the energy density and energy density become the same. Compare the integral flux. [not equal to dose. ]
Source: RadTech
Exposure
The effective radiant energy density of the surface; the time integral of the irradiance within the specified bandwidth, in J / cm 2 or MJ / cm 2. The time integral of the fluence rate in J / M 2 or J / cm 2. And radiation exposure. In the application of solar ultraviolet radiation, a larger unit - J / M ~ 2 or even MJ / M ~ 2 can be used. Compare the integral flux. [not equal to dose. ]The definitions of radiation chemistry and clinical chemistry are different.
Source: RadTech
