There are lot, depending on your requirements. Anyway you can try: QS_"fsyN:
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1, Refractive: an achromatic as positive + plano-convex as negative; 5x4JDaG2
OR #12PO q
2, Reflective: two parabolic mirrors; +n^$4f
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Both of them affer nice spherical aberration performance. K!HSQ,AC
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Reminder: compute the laser beam density, ensure you have enough strong optical coating. +UHf&i/3
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Good luck.