BYK-Gardner GmbH
System Description | 2
295 024 855 E 2010
spectro2guide Family
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2.3 Measurement Principle
The instrument is available with two different measurement geometries.
2.3.1 45°c:0° Geometry
The 45°c:0° geometry uses 45° circumferential illumination and 0° viewing
perpendicular to the sample plane. The circumferential illumination is es-
sential to achieve repeatable measurement results on directional and struc-
tured surfaces
The 45/0 geometry simulates the normal condition used for color evalua-
tion. For example, when we read a glossy magazine we position it to avoid
the gloss from coming into our eye. A high gloss sample with the same pig-
mentation is visually judged darker by the eye when compared to a matte
or structured sample.
2.3.2 D:8° Geometry
A sphere geometry illuminates the sample diffusely by means of a white
coated integration sphere. Baffles prevent the light from directly illuminat-
ing the sample surface. Measurement is done using an 8° view angle.
A sphere instrument may be operated under two different measurement
conditions:
specular included (spin)
or
specular excluded (spex)
. In the
“spin” mode, the total reflected light is measured. In the “spex” mode, a
gloss trap is used to capture the directly reflected light (gloss). Color is mea-
sured independent of the sample’s gloss or surface texture
