[Laser] Keeping beam tight for short distance

[Chuck Hast]

I need to keep a beam as tight as possible. at least from about 15mm from
the aperture to
about 170mm from the aperture. Beyond that distance I do not care.

The diode is a Osram 515 nm 10mw diode. Diode aperture is 5um. I would like
to try to keep
the beam width as near to 5um as possible for the distance of 15 to 170mm
from the lens
aperture.

Any recommendations?

-- 

Chuck Hast  -- KP4DJT --
I can do all things through Christ which strengtheneth me.
Ph 4:13 KJV
Todo lo puedo en Cristo que me fortalece.
Fil 4:13 RVR1960