How to collimate a DPSS-Laser (green)

[equal]

hi,

i have builded a simple, small DPSS-Laser

700mW 808nm IR-Diode -> ND:YVO4 -> KTP -> IR-Filter

Now, i try to collimate the green laser.
on a simple laserpointer, there is a acrylic expanding lens, and than a collimation lens.
Where can i get a expanding lens (glass) ?

Greetings

 

[diachi]

Actually ... that's a good question - one I haven't heard asked before.

You can find the lenses on their own on eBay.

5pcs 4mm Double Concave Glass Lens FOR 532nm Green Laser Beam Expander Expansion | eBay

10x5mm Duel Concave Glass Lens F 532nm Green Laser Module Diode LD Beam Expander | eBay

10x8mm Double Concave Glass LEN FOR 532nm Green Laser Module Diode Beam Expander | eBay

Will be other sources available I'm sure

Could always pull one from a working green pointer/module. You can also use regular convex focusing lenses in a telescope configuration. Actually the convex and concave configuration is still a telescope, just a different type.

See here for more: http://assets.newport.com/webdocuments-en/images/how_to_build_a_beam_expander_5.pdf

http://www.edmundoptics.com/resources/application-notes/lasers/beam-expanders/