I have a question about how to build the setup shown in the attached diagram. In the cuvette, there is an aqueous solution of two pigments, one absorbing at ~660 nm, and the other at ~940 nm. The concentration of both pigments in the cuvette will be varied (100 uM, 200 uM, etc), and I would like to measure the transmitted light that reaches the detector.
What electronic components and configuration would be most suited for this application? I am thinking of using the PDB-C171SMDKR-ND photodiode for the detector (both wavelengths), together with the 67-1647-ND (660nm) and 751-1203-ND (940nm) LEDs for emitters. I am fairly new to this, and would greatly appreciate any information on how to construct this system.