an optical device for producing and observing a spectrum of light or radiation from any source, consisting essentially of a slit through which the radiation passes, a collimating lens, and an Amici prism.
You'd need to have studied hard in school for science. In order to do this, you need to know the inner mechanics of each item. Then apply math to them and mix them together for hoping of the best.
no science NEVER EVER changes. over all these years science hasn't changed a bit. yes different people discovered different things but other than that science doesn't change and it never will!