I found what was called a "dichromatic prism" on ebay and bought it. It is a cube and although described as "not perfect" it splits light extremely well and is quite a cool object to show those in my staff room. I understand that dichroic is different but not sure how. Question is, how does it work? Considering it's made of what looks like a single piece of material how the heck did those almost invisible planes get in there. Cool it may be, but not understanding it is annoying. Can anyone help?