(f) Measurement of color difference

1. Visual assessment method

The personâ€™s eyes and mind can correctly explain whether the two samples are similar or not. Once identified as dissimilar, the color difference is much different and how the colors are different. Even though trained observers produce considerable differences in color difference determination, Differences, if measured by the instrument will be more objective, visible differences

2. CIE1976 L*a*b* color difference formula

The color difference formula goes down

â–³ Eab*=[(â–³L*)^2+(â–³a*)^2+(â–³b*)^2]^(1/2)
American swop recommends using the L*a*b* color difference formula as the standard for evaluating print colors.
(Source: Jiang Ruiyi. 1993.6)
COLOR DIFFERENCE
â–³ E*ab=[(â–³L*)^2+(â–³a*)^2(â–³b*)^2+]
=ã€(L1-L2)^2+(a1-a2)^2+(b1-b2)^2]^1/2

(seven) color measurement

The luminance and chromaticity of human perception can not be obtained from these measurement data from Table 2-2, but afterwards, applying the theoretical basis and developing the external appearance pattern has explored and solved this problem, and further the CIE proposed to use it in 1997. The CIECAM97 color appearance mode is used for testing. In addition, the brightness and saturation attributes can only be applied to the measurement of relative color, as observed in the normal environment, while for absolute colors such as light sources and luminance factors cannot be applied. The color difference formula was also developed because of the wide and accurate color difference formula of the land sequence after 1997. The new formula has roughly similar quality. (Li Xingwei, Su You, 1999)

Reference, experiment items and steps

The main content of this study is to analyze and compare the performance of inkjet printers on the market at the inkjet technology level for the actual output of special papers with different properties.

First, experimental paper

This study collected four different types of paper, as shown in the following table: Table 3-1 Experimental papers collected in this study

(i)(ii)(iii)(iv)(v)(i)(i)(i)(i)(t)(i)(d)

Single Color