OK, thanks for the clarification. Now, if the lens is indeed an asphere operating at a distance greater than its FL from the diode then it will cause a near field convergence (then divergence) and add spherical aberration. A second asphere operating in the diverging beam at a distance less than its FL from the focus may correct this.
What do you think about sorta "re-canning" these as I suggested?
What do you think about sorta "re-canning" these as I suggested?