Perfect Diffuse Transmitter
An ideal uniform diffuser with zero absorbance and zero reflectance.
A device for isolating narrow portions of the spectrum by dispersing light into its component wavelengths.
The degree of agreement of repeated measurements of the same property.
Any one of three lights in terms of which a color is specified by giving the amounts required to duplicate it by additive combination.
A standard whose calibration is determined by the measurement of parameters usually different from the parameter for which it will be used as a standard.
The ratio of reflected to incident radiation.
Process by which incident light leaves a surface or medium from the side on which it is incident.
The bending of light rays as they pass from one medium into another having a different index of refraction.
Process by which incident light is transmitted through an object in a rectilinear, straight-through manner, without diffusion.
The degree to which a single instrument gives the same reading on the same specimen.
The agreement attainable between measurements performed by different instruments in different laboratories.
To set the top of the standardization scale only.
The attribute of color perception that expresses the degree of departure from the gray of the same lightness.
The process by which light passing through granular, fibrous or rough surface matter is redirected throughout a range of angles.
All standards other than primary standards.
The grouping together of similarly-colored materials so that the materials within each group may be used together in a finished product.
Visible spectrum-sensing full-scanning or abridged spectrophotometer with either an integral microprocessor or a personal computer programmed to perform tristimulus integrations, normally with a broad bandpass of 10 nm to 20 nm.
An instrument used for measuring the transmittance and/or reflectance of specimens as a function of wavelength.
Spatial arrangement of electromagnetic energy in order of wavelength. For visible radiation, the spectrum is a band of color produced by breaking white light into its component colors.
Having the qualities of a speculum or mirror; having a smooth reflecting surface.
Process by which incident light is redirected at the specular angle, as from a mirror, without diffusion.
A reference against which instrumental measurements are made.
Process by which a given method, procedure or protocol is made to conform to prescribed conditions. Standardization can only follow calibration.
Limits that determine how far a sample can deviate from a standard. Tolerances can be set for any color scale or index parameter.
Diffuse plus specular reflection.