hello.

This is not hundred percent programming related question, but I was not able to find answer on the net.

Is there some kind of detector to record frequency/intensity of light radiation source? something like spectroscopy detector, but instead of actual machine, just the module which can be integrated in project. I have tried searching on Google but I do not even know what such device is called

if you know the more appropriate place to ask, can you let me know please.

Thank you