Tolerance Values
Numerical value that is used to determine the acceptability of a sample.

Transmission
Radiant energy which is transmitted through a material or an object.

Visible Color Spectrum
Spatial arrangement of components of radiant energy in order of wavelengths. The human eye is sensitive to the range 400-700 nanometers. The order of color spectrum seems like the color of the rainbow, and may be separated as follow;

- Violet 380-400 nm
- Blue 400-480 nm
- Green 480-570 nm
- Yellow 570-590 nm
- Orange 590-630 nm
- Red 630-700 nm

Wavelength
This term is used to describe light. The distance between two points of a periodic wave of radiant energy. Wavelength is defined in units of nanometers.

x
One of the CIE chromaticity coordinates calculated as the fraction of the sum of three tristimulus values attributable to the X value.

X
One of three CIE tristimulus values - the red primary.

X,Y,Z
Tristimulus values calculated from the set of reflectance or transmission values from a given batch.

X - Corresponds to Red stimulus
Y - Corresponds to Green stimulus
Z - Corresponds to Blue stimulus

y
One of the CIE chromaticity coordinates calculated as the fraction of the sum of the three tristimulus values attributable to the Y value.

Y
One of the three CIE Tristimulus values - the green primary

Z
One of the three CIE Tristimulus values - the blue primary