445nm beam collimation/correction

[edison]

Here,s the datasheet from Lightpath:

http://www.lightpath.com/literature/...Blue_Laser.pdf


Here the datasheet from the 405-g2:

http://www.laser66.com/html/405-g-2.pdf

Compare them and you will find that both are very similar. The one from lightpath is slightly more expencive but probably slightly better. i will buy a couple to compare them. Solarfire, if you can afford the 37.50 euro for a bare lens to compare with the 405-g2 then you can complete your test.

[Solarfire]

Didn't you test this lens and found there was a lot of low power crap around the beam? I have tested both lenses too and agree with you. I also agree that the 405-G-2 is a better option

Yeah, that was a while back. Unfortunatly there was a min order of 4 pcs. for the mccarrot lenses so im stuck with 4 of these now. I just now got around to posting the results of the 405-G-2 lens.

[Solarfire]

Here,s the datasheet from Lightpath:

http://www.lightpath.com/literature/...Blue_Laser.pdf


Here the datasheet from the 405-g2:

http://www.laser66.com/html/405-g-2.pdf

Compare them and you will find that both are very similar. The one from lightpath is slightly more expencive but probably slightly better. i will buy a couple to compare them. Solarfire, if you can afford the 37.50 euro for a bare lens to compare with the 405-g2 then you can complete your test.

I will do that, sounds like a winner! If I can blow 240+€ on a min order of 4 for the mccarrot lens, this will be a kindergarden lunch fund!

[mccarrot]

Hi Solarfire,

My supplier told me they improved the collimator to reduce the crap around the beam.

Can I take back one collimator from you so I can compare it with the new batch?

[Solarfire]

Hi Solarfire,

My supplier told me they improved the collimator to reduce the crap around the beam.

Can I take back one collimator from you so I can compare it with the new batch?

Sure, the problem didn't appear to be the lens itself but it seems the housing was the main issue here. Aside that, 50€ + Vat + shipping is just too much funding for this collimator, especially when the 405-G-2 proves to be so much better for half the price.


Here’s a quote out of the main post, don’t know if you saw it.

I managed to clean up the mccarrot setup. It appears there were some issues with reflections inside the collimator housing. I took the mccarrrot lens and put it in Daves mount, major improvement.

[Frixxion]

Where do you guys get these O-like lenses from? I can't seem to find it with the search feature on PL

,Jordy

[Doc]

I have also given it some thought to maybe limit the beam after the prism or cylinder correction (probably cylinders for getting down to 1-1.2mrad) with an adjustable knife edge aperture above and below the fast axis where the main trash is happening. I’m hoping to finalize a beam at 1 x 1-1.2mrad.

Frank

I have recently done this with alu foil (before the prisms) and it works perfectly, I'll post pictures next time a have my projector opened up.

[Solarfire]

Where do you guys get these O-like lenses from? I can't seem to find it with the search feature on PL

,Jordy

http://cgi.ebay.de/405nm-laser-445nm...item27b6f014d5

[LaNeK779]

I would make the hole 10.5 to fit the barrels from Laser4U and buy them in bigger quantaties and deliver it as a set.
But you can use the collimators from Laser66 because they are 10.5 mm in diameter and that its only 0.5 mm in difference. A thin brass Foil arround the brass collimators from Laser4U will do the trick to mount them in the block

exactly my thoughts on this

to be more precise, i measured the laser66 housing for the 405-g-2 using a micrometer and the diameter is 10.25mm. drilling a 10.5 hole in a piece of alu, it gave me just enough space for a tight fit and some arctic silver III in between (a really thin film).

edison, if the laser66 housing was 10.5 it would not fit in a 10.5 hole. it is just a happy fact that their machining has some tolerance, so that's why it fits. at least that is what i found out

still the maccarrot alu block is a very attractive piece of metal at a very nice price and to my opinion you can sandwich a thin alu or brass foil and some thermal grease to fill the 11mm hole. the screw at the top that acts as a lock-in-place also helpes to secure a better contact / thermal interface

i haven't tried the maccarrot collimator, but i am more than happy with the 405-g-2 results, especially for knife edging. and i am waiting for some o-like lenses and see how they do with a p1t8ull pbs



ps. yes yes yes!!! i saw my first 445 dot / ray this weekend and i was too happy to take pictures and measure beam specs. i was just monkeying around like a small child. as soon as i feel more serious i will post some pics. nothing earth shattering in terms of implementation, but it is MY first blue module

and i think while building this i set the world record for divergence, i got a line of almost 75cm across at 2 meters from apperture. as soon as i saw this, i ran for the trees nearby and stayed there. after regaining my calm i found out that the diode had not sit where it should within the lens holder and was further away from the lens than i thought



edit: How can i tell that a diode - lens combination is in focus???? Of course i can trust my eyes and see what happens as i move the lens, but is there some sort of "method"? Not much came up in a search i made here.

as an example, when focusing the 445, can i consider that everything is in focus when i get the smallest crispiest line available? because the temptation to overdo it and go for a spot instead of a line is strong

[edison]

You can focus the lens until you have a line. Kniveedging 3 next to eachother with o-like lens will get you a good powerfull beam. That is only for a few minutes. When things start to get hot the power drops so tec cooling is needed. Yesterday i have had my quad red for a few hours and it did 950mw with LPC822,s. I have now my quad blue doing 4 watt but the power drops fast without tec cooling. You can set the blue lenses also slightly out of focus so that when knivedging them next to eachother the stripes will surely touch eachother. You lose some power but not much. I would prefer to set them in focus so that every diode produces a thin stripe. Then setting them next to echother real close will get you a the best beam. With 2 diodes you can use a prism pair but with more then 2 its not possible to use prisms any more.