Sorry...just saw this post !!! Yes....transmission loss thru the wave plate is less that 1%... Like I said....all one has to do is have the round glass filter/wave plate....spun in the correct position....and in the path of one (1) of the beams.
WHAT ????? Take a pic of what you have....and maybe we can start there !!! Maybe...but I seriously doubt it can be done with any degree of cost effectiveness....sorry...luv stinks....truth hurts !!!
What you are attempting takes a special set up....READ....DEMANDING....Not easy !!!!!!!!!!!!
The optical design must begin from the start....It is extremely difficult with a custome set up....and to try to use a pre-existing unit....and design/machine a way to accurately fit it all together.... Well...Maybe doable....but....well....just not the way to go !!!
I am not trying to be a Wise Ass....BUT....Just using a set of Cylindrical lenses is challenging enough !!! Alignment and lens to lens spacing is critical !!!
Now...Add in the demands of a Beam Expander.....WOW....another magnitude of difficulty !!!.....as the corrected beam MUST enter the Beam Expander....almost perfectly in the center of the BE lens !!! NOT EASY !!!:yabbem::yabbem::yabbem:
I will throw a link on here showing a Blue LD + Cylindrical lens+ Beam Expander.....again....one of the most demanding Hand Held builds around !!
Are you looking for correction or just pure expansion? A combination of the lenses offered at those links could be used as a beam expander (telescope) but wouldn't offer any beam shaping or correction.
Generally when we talk about correction we're talking about correcting the shape of the beam itself. As you're probably aware the output from these LDs is a fat stripe. This is a result of the geometry of the optical cavity itself, which results in a higher divergence on one axis. To correct that requires expansion in only one axis, meaning you need an optical setup that only refracts the beam on one axis, either a cylindrical lens pair or an anamorphic prism pair. A standard telescope using spherical lenses results in expansion on both axes.