I must choose a topic for my project in optics - Physics , any suggestions ?

Question

Level : 2nd year university ...

Answer 1

I made helium and methane lights using glass coke bottles.

Answer 2

Make several "aquariums" with different widths (for example: 1cm, 2cm, 5cm) and fill them with water and different concentrations of salt of other solutes. Use a laser to project on the surface and derive refraction coefficient on a back panel (you will need several measurements and use regression analysis).

Not terribly original but enough to show how to use lab techniques and theoretical knowledge together.