How do instruments calculate things using absorption of light?

[Nerdydude101]

Supposedly devices use special algorithms to determine specific things about an object by its absorption or reflection of light, how exactly would such equations work? (if this isn't calculus then please tell me and ill post it somewhere else, i wasn't sure what type of mathematics this would be)

 

[adjacent]

Supposedly devices use special algorithms to determine specific things about an object by its absorption or reflection of light, how exactly would such equations work? (if this isn't calculus then please tell me and ill post it somewhere else, i wasn't sure what type of mathematics this would be)

Provide an example of a device of that kind.

 

[Nerdydude101]

Watch the video
https://www.kickstarter.com/projects/903107259/scio-your-sixth-sense-a-pocket-molecular-sensor-fo

 

[Sunfire]

Google "differential reflectometry", for instance