BUCHI NIRFlex N-500 - Manual (Page 23)

4 Description of function
23 NIRFlex N-500 Operation Manual, Version F
4 .2 .3 Transmission mode
NIR light is sent through a defined pathlength of sample material (e.g. in a cuvette). The transmitted
light contains the spectral information. This is the preferred method for testing liquids.
Detector
Cuvette
NIR light
pathlength
4 .2 .4 Diffuse transmission mode
The diffuse transmission mode is a mixture of “diffuse reflection” and “transmission” mode.
The NIR light penetrates the sample:
is refracted •
diffusely reflected •
diffusely transmitted •
The transmitted rays contain the spectral information of the sample.
Detector
NIR light
Sample Collecting lens