HI Mr narmu,
I am sorry. My mistake I did not notice that colorimeter is a different thing. I am a service engineer and basically deal with analytical instruments, so about some time ago we had installed a calorimeter at a customer place since it is used to measure the specific heat of substances under different temperatures.
But still what you seem to be doing is interesting, so what you intend to do is it based on measurement of ion mobility in different wavelengths of light. Is this a project to you?