Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Divergence?

Things

New member
Joined
May 1, 2007
Messages
7,546
Points
0
hi, i just got my DX 30, but when i tested it at about 5 meters, the dot was about 1cm big!!!! :eek:. is there any way to improve the divergence?
thankyou
 



pseudonomen137

New member
Joined
Oct 24, 2006
Messages
2,032
Points
0
Only way is through "upcollimation". In order to improve divergence, you need to have a larger beam size. So what you do is use one stronger lens to diverge the beam and then catch it with a weaker lens to re-collimate it. If you get it all aligned well, you'll have a thicker beam, but lower divergence.
 

Things

New member
Joined
May 1, 2007
Messages
7,546
Points
0
would it be possible to "ajust" the lens inside the laser?
 

pseudonomen137

New member
Joined
Oct 24, 2006
Messages
2,032
Points
0
things said:
would it be possible to "ajust" the lens inside the laser?
No, there are limits to how good you can get it and I'm sure its already set close to that value.

things said:
also would temperature adjust the divergence?
Temperature could affect divergence to a degree. Its not like you can change the temp though and get it so it doesnt diverge much if that's what you thinking. Sorry!
 

Things

New member
Joined
May 1, 2007
Messages
7,546
Points
0
well it's about 12 degree's celcius here at the moment, and the instructions say "do not operate above or below temperatures 20-30C" so maybe that's the problem?
 

pseudonomen137

New member
Joined
Oct 24, 2006
Messages
2,032
Points
0
things said:
well it's about 12 degree's celcius here at the moment, and the instructions say "do not operate above or below temperatures 20-30C" so maybe that's the problem?

No, what you describe is ~2mRad divergence. That's pretty typical for a NewWish, may even be above average. Even if it weren't a NewWish, the best you normally get is with the RPLs, and even the very best of those only get to ~0.7mRad I think.

The temperature dealy is because the laser is more efficient at different temperatures. As temperature changes, the laser diode wavelength changes and that makes the crystal efficiency change. That's why they say 20-30C, because these portables are often temperature tuned for operation ~room temperature. Wouldn't really worry about it affecting divergence much though.

BTW, why the hell is it 12 celsius there? :eek:
 

Things

New member
Joined
May 1, 2007
Messages
7,546
Points
0
cos it's winter ;)oh, it's 12 degree's celcius not farenheit ::)
 

pseudonomen137

New member
Joined
Oct 24, 2006
Messages
2,032
Points
0
things said:
cos it's winter ;)oh, it's 12 degree's celcius not farenheit ::)
Even so, that's pretty cold for indoors :eek:. Perhaps you meant outside? Otherwise you may want to set something on fire over there!
 

Things

New member
Joined
May 1, 2007
Messages
7,546
Points
0
that's why i have the heater on ;D ;D ;D ;D it was 8 degree's at 8:30 this morning ;D and surpisingly enough, we get some frost on somedays down on our backyard :D haha, i just realized, we haven't gone over 15C this whole fortnight :eek:
 







Top