I have been struggling in the past weeks to understand how should I setup a laser interferometer for my experiment. I am not a physicist, and I am quite new to optics.
I have a Cassegrain telescope with a primary mirror M1 and a secondary mirror M2 and I want to monitor the relative displacements and tilts between M1 and M2. How can I obtain that output with the minimum number of optical components? I am also not sure about the detector I should need. I was thinking of a simple system that I don't know if it could actually work. I still have to purchase the components, but the budget should be around 2K.
First of all, I thought that cornercube retroreflector on both M1 and M2 would be necessary. With flat mirrors the beam would not be reflected if there is some tilt, right?
The laserbeam passes through a beamsplitter: one half goes to a right angle prism and then toward the retroreflector on M1 (can it count as the reference beam?). The other half goes to the retroreflector on M2. The beams from M1 and M2 are then recombined in the beamsplitter and the interference beam goes to the detector (PSD, quadrant photodiode?)
Would a system like this be able to give me as output the relative displacement (like a classic Michelson interferometer) and maybe the tilts (looking at the current in the quadrant photodiode perhaps)?
In the picture: LS = laser source, BS = beamsplitter, P = prism, R1-2 = retroreflectors, QPD = quadrant photodiode.
Thanks in advance.