I'm quite surprised that this has been accepted. The process is well known and called multi-plane light conversion (MPLC). The theory for this is from the 90s a

I'm quite surprised that this has been accepted. The process is well known and called multi-plane light conversion (MPLC). The theory for this is from the 90s and there are even products based on this (the company is called cailabs). The typical way for doing this is using reflective optics such as LCOS displays (if reconfiguability is desired) or lithographic reflective devices.