Anyone here used a compander for R,G,B laser diodes combining all or even for one?

Has anyone here used a compander for R,G,B laser diodes combining all colors or even for one wavelength? I found an old thread where the OP posted the following images:



I found these images using google image search as the original full sized photo's in the thread no longer exist, hoping to find someone who has built one.

That's pretty much what the knife-edging technique is doing. Getting those beams to line up nicely takes effort and additional optics to align, and that effort is better spent if you want to combine multiple lasers of the same wavelength because of the limitations in how such same-wavelength lasers can be combined (e.g. with a polarized beam splitter).

More light shed on the subject, thank you. I was hoping to make a laser pointer I could combine the ratio of wavelengths in different proportion to make different colors. Combine and then expand to reduce the divergence. Although, I am not so sure expanding after combining together isn't just two steps back and useless.

Edit: thinking upon this more today, then the thing to do would be to combine all of the R, G and B's separately, once I have the combined outputs for each color maybe I could find a way to combine them to make one of seven colors, depending upon the mix. I've been looking at Fresnel lenses as a possible way to do this for the output lens. The reason I have an interest in them, even with their distortions, is they are light weight for the larger diameters, far more so than a glass lens as well as have less loss. I have a 12 inch diameter glass lens I was thinking of using for the output lens, as a huge expander output, but it's very heavy.