Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[kiyoukan]

i am using lenses coated for 405nm.
the dot is decent no wings or anything.
headed to the irc now.
okay so now i am confused.
i was told the best lens to use is the 405-g-2
http://www.laser66.com/html/405-G-2.pdf
this lens.
6.33mm dia., 4.00mm EFL, 2.40mm BFL, NA= 0.60,
i thought we wanted the effective focal length to be between 2 and 3?
and the 650-G-2 Collimation Lens
has EFL = 4.56 mm
BFL = 2.90 mm
So i can understand why that is worse.
i was looking at Edmunds for some short 2.05 EFL lenses.
Any one tested any of those?

[CDBEAM]

Dave....What is the spec on your short fL collimation lens ( Lens with adjustable LD mount ) ??????? 3mm or less than 3mm ?????

AndyF.....do you have any results yet on your set of trial lenses ????? What FL did you order ??? What FL have you found to be the best ?????

BEAM

[LaNeK779]

Dave's lens has a focal length of 2.9mm and na of 0.55, more than enough for no clipping at all

[dave]

Cheers man,

Right at this very moment, I'm using them with HL63133's for a pair of 6 diode modules.

Dave's lens has a focal length of 2.9mm and na of 0.55, more than enough for no clipping at all

[drlava]

Hi guys, shipped out some correction lenses this week. I have heard some people say that if the zoom was larger on these correctino optics that it would make the beam perfect. I'm a little skeptical of that, after all the near field beam needs to fit on a typical set of scanners. In order to make a little more progress, why don't we start by doing a small buy of some higher mag cyls (I can order 5 sets) and send them out for testing. In order to best estimate what their mag should be, please post what you have been seeing with the 405-g-2 4mm EFL lens and correction:

Divergence without correction: x.xx mrad
Near field expanded (corrected) slow axis width, cyls 1 inch from collimator: x.x mm
Far field corrected slow axis width xx meters away



With these simple data points I can order up some new test lenses for you! In the mean time the broadband 445-designed set is still available at the site I linked.

[Solarfire]

Hi Andrew,

With the Optima lens (fl = 4mm, NA = 0.5, red coated) with no correction I got 8.57mrad.
With the cylinders I got 1.8mrad divergence with the 1st cylinder @ 3mm from the Collimator and 4mm x 1.5mm @ the 2nd cylinder aperture.
With the 1st cylinder @ 100mm from the collimator I got 0.8mrad and 4mmx4mm @ the 2nd cylinder aperture.

[steve-o]

When my cyl-lenses get here I will be happy to post that info too Dr.L.
How's the move going? Got any furniture yet?

[badger1666]

@ dr lava
with dave's 2.9mm fl lens , first lens at 64mm 4x4 beam 1.09mrad, no mystry beam wings after your lens

[steve-o]

Slightly off topic but semi related because some are in use with the G71s I'm sure: aixis press-fit diode holders.. what are they made out of? They don't feel like aluminum , more like stainless steel or something. Filed one down and still silver colored, not brass or copper. Makes me wonder about their heat transfer efficiency from the diode..
__

[Doc]

Slightly off topic but semi related because some are in use with the G71s I'm sure: aixis press-fit diode holders.. what are they made out of? They don't feel like aluminum , more like stainless steel or something. Filed one down and still silver colored, not brass or copper. Makes me wonder about their heat transfer efficiency from the diode..
__

Maybe there's some different manufacturers as the one I filed down appeared to be plated brass