Most colorimeter instruments adopt 8 / d illumination optical structure shown as Figure 1, including a light source, the light path, integrating sphere sensor. Other illumination optical structure with this little difference.
Figure 1
Our NH series, and some NR series use 8/d illumination optical struture, while NR20XE, NR145 coloriemter and NS800 spectrophotometer use 45/0 method (45 ring-shaped illumination, vertical viewing). Only our NS810 spectrophotometer uses d/8 (diffused illumination, 8-degree viewing angle)