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Color difference
The standard instrument will calculate and display three dimensional color difference in
uniform color space (Lab) coordinates. Uniform color space defines three directions, a
Light to Dark direction, called
L*
, a Red to Green direction called
a*
, and a blue to
yellow direction called
b*
. Two measurements are used to calculate color difference; a
sample, and a standard. We compare the sample to the standard by calculating the
difference in each of the three directions. We can also calculate a total color difference,
called DE or Delta E. The standard may be one of the measurements we have made with
our instrument or may be a numerical standard established by another instrument and
installed in our instrument from a personal computer using the RS232 interface.
Standards installed over the RS232 interface may have text names of up to 16 characters.
Thus when we calculate a color difference we will have two storage locations,-- one for
the sample and, one for the standard; four numbers DE, DL*, Da*, and Db*, and a 16-
character name. To accommodate the display of this information there are three color
difference displays.
If the desired display is already enabled, and the arrow keys are set to
Toggle Display
,
then you will be able to use the arrow keys to examine color difference for any sample.
The display of the form
shows the total color difference (DE) and the three components of this difference (DL,
Da*, and Db*)
The display of the form
shows the sample (011) and standard (010) used to calculate the difference, and the three
components of this difference (DL, Da*, and Db*).
The display of the form
DE*=0251DL*=0128
Da*=0135Db*=0169
#011/010DL*=0128
Da*=0135Db*=0169
#011/010DE*=0251
Measurmnt 010
