What is the difference between these two 500mW 532nm diodes?

[geeeee12345]

Ok so am looking at purchasing two 500mW Green diodes to replace my two 100mW....

Looking on ebay have seen these two but am not entirely sure of the difference and if any which would be the better or are both a bad buy?

Could anyone suggest someone or somewhere to go where I could pick up two for roughly the same price (budget is tight) unless either of these are ok?

http://www.ebay.co.uk/itm/500mw-532n...item2a170a0fef

http://www.ebay.co.uk/itm/500mw-532n...item27c157fa88

Any help is greatly appreciated

[norty303]

You may be interested to know that I've got a pair of the CNI MGL-H 500mW heads (analogue modulation) that are as new, but surplus. Just power tested.
I'll be putting a for sale thread up soon (not enough time tonight) with graphs of the power, etc, and more details about the circumstances of the sale.
They'll be cheaper than the meierlight price.

[geeeee12345]

ahhh if they be better & cheaper than those on ebay then I would rather go to you n support the trade!

The reason for the upgrade is I have a job coming up in June for a local festival, the previous year was a friend who used his two green 500mW of which I need to be equal with in order to pull off an equal show...

here is a vid of him at the fest.... Do you think those diodes you have will do the job?

Cheers
G

http://www.youtube.com/watch?v=EBs0qbntKjo

[geeeee12345]

however still out of interest what are the differences between the two diodes???

[taggalucci]

The correct technical term is "modules" i.e. "what are the differences between the two modules". Diodes are certainly a component within these, but they're not green, they're infra-red!

I'm not sure what the differences are between these two modules without spending some time looking at the eBay postings. I may get a chance to look later on today.

[dnar]

Ok so am looking at purchasing two 500mW Green diodes to replace my two 100mW....

Looking on ebay have seen these two but am not entirely sure of the difference and if any which would be the better or are both a bad buy?

Could anyone suggest someone or somewhere to go where I could pick up two for roughly the same price (budget is tight) unless either of these are ok?

http://www.ebay.co.uk/itm/500mw-532n...item2a170a0fef

http://www.ebay.co.uk/itm/500mw-532n...item27c157fa88

Any help is greatly appreciated

The module in the first link has a tighter beam specification (<1mrad compared to <1.5mrad but they may differ in reality).

Both are TTL modulation, the first 10kHz, the second 5kHz. Neither is flash, nor suitable for projection IMHO. But that's just the drivers, they could be swapped out with all the re-alignment issues that raises...

I don't recognize the first driver, the second is a CNI OEM driver (I have one of these).

If you can afford Norty's module(s) I am sure you will get a better product.

[norty303]

ahhh if they be better & cheaper than those on ebay then I would rather go to you n support the trade!

Just to be clear, I'm not in the 'trade' as such.
I just needed some matched pairs of heads, so bought more than I needed, graded them, and selected the best 2 matching pairs. The 2 for sale are the ones that didn't match best with any of the others.
They are just like the CNI heads in your picture, but analogue drivers.

Through my testing process, I graphed them at CW and with a couple of different types of modulation, which although not hugely scientific, allow me to see how they react under modulation.
Probably best if I don't write too much more here, as I'll be putting it all in my sale thread tonight hopefully, with graphs etc.

One is giving 800mW+, the other 600+, but as the old saying goes, a picture tells a thousand words, so I'll leave it til then.

Out of all the heads , the higher power one for sale was in the upper 20% (shame I couldn't find a match for it )

As a pair, they aren't optimally matched, but I guess you could find yourself in the same position buying 2 heads elsewhere. Out of 6 heads tested, the variation from top to bottom was >400mW!!

[geeeee12345]

dnar, thank you for the info there... much appreciated

Norty if you can give me a heads up when you post and if it be in my price range the chances are I will say yes straight away.... luckily these will just be used as beam show and not for graphics projection

[geeeee12345]

Please excuse my lame Paint skills here.... but this at present is my setup, minus some lighting fixtures, scans, moonflowers & parcans. I am wanting to upgrade my two 100mW green lasers, in theory as it is not graphic projection then the variation (even though quite large) should not really make much difference to what I am going for would it???

[norty303]

In my experience, if you are using just a single colour on its own, then differences in power are less obvious.
The time when you DO notice is when you mix with another colour, as the shades can change quite dramatically, even with small variations.
This was my reason for looking for matched pairs in the first place, as my current pair of 300mW heads are quite different in their characteristics, and produce quite different shades of yellow/orange (cyans/light blues seem less affected for some reason).
I could just get some colour correction boards, but I prefer to have them as close as possible 'natively' as I can, and avoid another step of complexity in my projectors.