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FrozenGate by Avery

Casio M140 diode and prism pairs

Joined
Jun 30, 2008
Messages
1,660
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Will a casio m140 diode with a g2 lens and 2 prism pairs get me a nice beam?
Someone already tried this?

just wondering :)
 





The beam profile of the two diodes are VERY similar

It should act virtually the same through the prisms

Peace,
dave
 
The beam profile of the two diodes are VERY similar

It should act virtually the same through the prisms

Peace,
dave

The "2" diodes?
Im indeed trying to compare it to a older diode from casio i have, but i didnt say that in the topic? :O
 
Sorry for being unclear.

The beam profile of the A-series diodes
and the beam profile of the M-series diodes
(the two diodes)
are virtually identical

The A-series diode HAS been shown to improve significantly using a prism pair

That is good reason to believe that the M-series diodes will show the same level of improvement when using the prism pair

Peace,
dave
 
I can confirm this. I upgraded my A140 in my projector to an M140 with a G-1 Lens (Same as the G2)

It gives an excellent beam with a prism pair, very close to a perfect round beam.
 
I can confirm this. I upgraded my A140 in my projector to an M140 with a G-1 Lens (Same as the G2)

It gives an excellent beam with a prism pair, very close to a perfect round beam.

Very nice. thanks for sharing.
Cant wait until i receive my new laser.
The one i have now acts weird as it jumps all the time in power(might be the supply as well) and cannot take more then 680mW, because else it becomes unstable and will drop in power.
I know i can at least get 1W out of this little new diode. I hope i can get it to reach 1.5W in my heatsink.
 
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I can confirm this. I upgraded my A140 in my projector to an M140 with a G-1 Lens (Same as the G2)

It gives an excellent beam with a prism pair, very close to a perfect round beam.

Could you do a photo/diagram that shows the prism angles?

I've tried to correct the 445s beam with a prism pair, and while i get a significant improvement in the beam profile, i've never managed to get it anywhere near round.
 
Could you do a photo/diagram that shows the prism angles?

I've tried to correct the 445s beam with a prism pair, and while i get a significant improvement in the beam profile, i've never managed to get it anywhere near round.

Attached a PDF file for you:)
Thats how the prisms should be.
i also found out that those angles dont matter 100%. the second prism can have alot of movement, it will just move the beam.
 

Attachments

Thanks.. i'll tinker with it some more - what do the numbers mean?
 
I've just given it another try, see the pictures for the results.

The beam isn't quite round yet, but the improvement is a factor 2 to 3 in the fast axis, so still pretty good. Target distance is about 10 meters here. I'll probably need some longer path to do fine adjustments, perhaps bounce it back with a mirror for a total path of 20-25 meters indoors.
 

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I've just given it another try, see the pictures for the results.

The beam isn't quite round yet, but the improvement is a factor 2 to 3 in the fast axis, so still pretty good. Target distance is about 10 meters here. I'll probably need some longer path to do fine adjustments, perhaps bounce it back with a mirror for a total path of 20-25 meters indoors.

Try something more like this:

http://nqlasers.com/scannerreference/images/9/90/Laserwithoptics.jpg

The zoof prism templates are good, it will help the beam, but not correct it fully. Trying moving the prisms around and see what works for you, having them like in the picture above worked really well for me.
 
That looks like a very nice build. And i think i need to put something more sturdy together for the final best result here.

The tricky bit is actually aligning it - once you get close to the best result its difficult to see the spot very clearly at that distance. Making a long path with a mirror will probably fix this problem since i can watch the result up close while making adjustments then.
 
i also found out that those angles dont matter 100%. the second prism can have alot of movement, it will just move the beam.

Angles define the ratio how many times a beam is compressed or enlarged. Yes, the second prism corrects the direction though it contributes to compression/enlargement too.

Sometimes an additional cylindrical lens is used to correct diodes astigmatism.
 
I'll be happy when it looks more like a square then like a line at 50 meters distance :D
 
Il make a pic of my blue when im home. Almost perfect round dot, very nice.
edit: i cant, i forgot i already removed the diode because im upgrading soon....
 
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