MICRO-EPSILON colorSENSOR CFO, Руководство по эксплуатации

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Functional Principle, Technical Data
colorSENSOR CFO
The system can be set to the distance models Sphere (∆E), Cylinder (∆L; ∆ab), Box (cuboid, ∆L; ∆a; ∆b) and
Classify. These models form a tolerance space around the learned colors.
C
m
C
1
2

E
L
b
a
L
b
a
C
m
C
1 2

L
2

a b
L
b
a
C
1
2

a
2

b
2

L
C
m
Fig. 2 Tolerance space Sphere Fig. 3 Tolerance space Cylinder Fig. 4 Tolerance space Box
C
1
= learned color 1
C
m
= detected color
For an evaluation of color deviations, the color tolerance parameters should be based on the perception
thresholds for color differences. In the Lab color space, a tolerance threshold of ∆E > 1 is frequently used for
perceptible color differences.
Influencing factors for setting color tolerance parameters:
- Required accuracy for color recognition
- Tolerance for reading variations.