There are two cases I'm asking about. The square in the middle is a cube beam splitter in the same orientation for both cases. We are looking at the beam splitter from the top. In the first case, the beam comes in from the left and half gets transmitted and half gets reflected downwards.
So, now changing only the beam direction in case 2, with the beam splitter in the same orientation, will the beam split like I've drawn? Does the beam splitter work if the laser comes from opposite directions?
What would happen if the Beam came from the top direction? The bottom?
Does the beam splitter only work one way?