Re: Spreading beam from green laser

Steve <nospam@xxxxxxxxxxx> writes:

I have a 120 mw 532nm DPSS laser and I would like to spread the beam at a 30
degree angle in order to illuminate a larger area than would normally be=20
possible (that is, to project a larger spot size).

The beam coming from the laser seems to be about 1.5mm diameter (the
exit= hole from the laser is about 3mm diameter), and the divergence
seems to be = much less than a degree. The exit end surface of the
laser is 22mm in diameter.

What would be the best way of doing this? A plano concave lens
glued on to the end of the laser seems like the way to go, but I
don't know how to = calculate the EFL or what diameter lens to use.

For a simple lens, just figure f1/d1=f2/d2 where f1 is the focal length
and d1 is the beam diameter. Then f2 is the distance to the object or
screen and d2 is the projected beam diameter at the screen.

Try a DVD or CD objective lens.

Didn't you ask this Yesterday?

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