Dichroic mirror confusion

[nuphotonix]

In looking at yet another projector,
This setup has the red laser passing through the BDM and GDM. is that right? How can I tell which one is which?
I am totally confused right now.. I thought the green passed through all the dichroic mirrors as in my 2 watt rgb..
Anyone have any insights on this?

[taggalucci]

If you hold a dichroic mirror up to the light, when angled at approx 45', you should see the reflected light colour that is optimized for reflection, when you angle it to look straight through it, you should see the colour change accordingly to the light colour optimized for transmission.

[nuphotonix]

Bingo!! thank you SOOo much!

[taggalucci]

Don't forget there is a right side and a wrong side to a dichro. The coating is on one side, so be sure that is the side you are using to reflect off.

[steve-o]

This remined me of a question I have, (I'll post on a separate thread if necessary) is there an "input" and "output" side to a PBS cube or just whatever works is ok? Thx. (sorry for the threadjack)