Homebrew PCBs

>You're going to have the same problem with a laser, except the beam will
>start out with a 1-2 mm diameter

actually 0.2mm with low divergence. This was the real reason of choosing a 
laser.

>  instead of a 15 degree divergence.
>
>Your problem is the same as that of a microscope. So consider using the
>objective lens of a microscope possibly along with an ocular lens. Just as
>with a microscope, you'd have to manipulate the distance in order to focus
>on the object plane.

I'll do. Don't know its spectral response, but I'll check.
Cristian