Altana 345 000 016, Руководство по эксплуатации

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BYK-Gardner GmbH System Description | 2
295 024 855 E 2106 spectro2guide Pro 21
2.4 Measurement Principle
The instrument is available with two different measurement geometries.
2.4.1 Geometry 45°c:0°
The 45°c:0° geometry uses 45° circumferential illumination and 0° viewing per-
pendicular to the sample plane. The circumferential illumination is essential to
achieve repeatable measurement results on directional and structured surfaces
The 45/0 geometry simulates the normal condition used for color evaluation. 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 pigmentation is visually
judged darker by the eye when compared to a matte or structured sample.
2.4.2 Geometry d:8°
A sphere geometry illuminates the sample diffusely by means of a white coated in-
tegration sphere. Baffles prevent the light from directly illuminating the sample
surface. Measurement is done using an 8° view angle.
A sphere instrument may be operated under two different measurement condi-
tions:
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 measured independent
of the sample’s gloss or surface texture