445nm lensing options - discuss them all here!

[dave]

First tests show a half divergence of 0,5mRad at the small side and 1,6mRad at the wide side is possible.

(or 0,1 x 1,3mRad half angle like Kvant like to rate there lasers: eek

Sorry man, I just had to

[mccarrot]

Dave to be clear, the 0,5 x 1,6mRad FULL angle was with a different lens and a limiting aperture.

0,2 mRad x 2,5mRad Full angle was with the bare collimator I have on my webstore.

to compare A 500mW Kvant module does 0,4mRad x 1,6mRad full angle, but if i'm correct this is with a anamorphic prism pair in the beam path.

[dave]

Sorry man, I assumed when you said "half divergence of 0,5mRad at the small side and 1,6mRad" you meant half angle divergence.. My mistake...

[mccarrot]

Why are some companies using half angle instead of full angle? is there a real reason for it , or is it just because the specs look twice as good?

[Zoof]

I wondered about that as well and believe that the tendency to use half angle divergence comes from the world of optics where it is probably more useful in equations than the full angle, which is more meaningful to us.

[shrad]

this evening I'll try to mount a tiny 2mm dia fiber optic in front of the diode window to correct the fast axis

if it works, you'll have a 10 cent per diode solution, if not I'm stuck to the cylinder lenses or prisms

I can't see a reason it could fail, expect the fact that the fibers are acrylic

anybody know of a place where we can buy small diameter glass rods for cheap?

[drlava]

Last evening I did some quick test with the High quality collimator from my webstore.

Out of the aperture there is a clean 3mm beam, after 30 meters I ended up with a line of 8mm wide and 80mm long

this give me a fast axis divergence of less than 0,2mRad full angle, and aprox 2,6mRad at the slow axis full angle (or 0,1 x 1,3mRad half angle like Kvant like to rate there lasers: eek
.

Ok, there's another data point, but what is the effective focal length of that lens?

[mccarrot]

If I remember well it is 4,1mm

[jaycey]

Here is a picture of my spot at 10metres using the lens and diode mount from a Plasmon UDO Drive.
Its around 2.5cm, not bad me thinks



Heres a beam shot in broad daylight



Got this in a little handheld project box, connected to a LM317 (DDL Design) driver at around 600mah, running off a 7.4v 800mah LiPo.

Until I can get a Flexmod then its going in my projector.

[mccarrot]

Here is a picture of my spot at 10metres using the lens and diode mount from a Plasmon UDO Drive.
Its around 2.5cm, not bad me thinks

assuming a beam diameter of 3mm in the begin will give a divergence of 2,2mRad