Re: optics of choice

comozo@xxxxxxxxxxx wrote:

>When constructing a Galilaen beam expander which is the lens of choice,
>a Plano-concave or Bi-concave?
>
>Thanks
>Steve

Laser beam enters the smaller lens from the flat sides and exits from
the concave side (which needs to be a conic to remove spherical)

Then diverging beam stikes a convex surface (also a conic) and leaves
from the final flat side.

Conic constants are determined using an optical design program or
through a lot of algebra to determine the conics which work.

Jim Klein
.

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