materials / possibilities of and for lenses?

Hey there!

I want to build a real small laser (as small as possible).
As far as my knowledge goes any laserdiode needs a lens to reach its full concentrated power.
right now I am using a red laserdiode I harvested from a 16x DVD burner.
Now what lenses would be best for using with this little diode?
I know about these laser housings with built in lenses but they are still too big for what I am planning so are there other possibilities?

Can I use the plastic lenses that came with the DVD burner?

What other materials make good lenses? I thought it would be really cool to have some kind of red gem before the laser (can it even pass through this and maintain its power? or can I use a gem shaped lense?)

What about focusing? Are these prebuilt laser housings the best bet or is it possible to get a smaller focusing system? what are the advantages of focusing?

Any help is higly appreciated

You can use any lens that will collimate your Laser's
beam as long as the material of the lens does not
get damaged by your Laser's output.

Jerry

Thanks for your reply.
I was hoping to get a little more detail about that since I dont really know what laser influences wich material. Is any collimator lense appropriate for any laser?

Also I am looking for really small lens systems and was hoping for suggestions

It doesn't hurt to try the lenses you already have from the sled. Just move it closer and farther from the diode until you find the focal length and the output turns into a dot at distance. However, chances are that these lenses will have a rather long focal length, so a lot of light will not be collected by the lens.

You can buy some of the single aspheric lenses that members here sell. The actual lenses are quite a bit smaller than the 12mm diameter of the modules. They will have much shorter focal lengths than the lenses you generally find in sleds, so they will produce a dot at distance while being closer to the diode.

You see them here referred to as 650-g-1 or something weird like that.

BShanahan14rulz said:

It doesn't hurt to try the lenses you already have from the sled. Just move it closer and farther from the diode until you find the focal length and the output turns into a dot at distance. However, chances are that these lenses will have a rather long focal length, so a lot of light will not be collected by the lens.

You can buy some of the single aspheric lenses that members here sell. The actual lenses are quite a bit smaller than the 12mm diameter of the modules. They will have much shorter focal lengths than the lenses you generally find in sleds, so they will produce a dot at distance while being closer to the diode.

You see them here referred to as 650-g-1 or something weird like that.

Click to expand...

thanks that sounds good.
how about materials? are there any limitations to what the lens can be made of?