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FrozenGate by Avery

My 8X at 440mA

HOLY CRAP! I couldn't have asked for a more thorough answer. Thank you very much for that. I really appreciate the info. It is something I often questioned when I see people "decanning" diodes. I think I will leave the window/can on for my next build. Should be done in a 10 minutes or so. Be right back.
 





Well looks like I have one upped myself. I left the window on my new 8X build. It uses the same diode and same driver. I have modified the driver to allow for high voltage input and I am using 3 10440 batteries. This should provide plenty of run time and the current will not sag like it does with my other 8X. The host is a MXDL 3405 with a hefty heatsink which is drilled out with minimal free space allowing for good heat transfer. The lens is a LARRYDFW The output is incredible. I have never seen so much violet. I do not know if it is a high wavelength or possibly a more efficient diode but it is only being ran at 400mA and it is clearly more visible than my other 8X. I really need to get my Laserbee before I can make any solid conclusions.
Here are a few photos. i measured the current before these photos as the batteries were not 100% on all.
The least bright is an 8X at 320mA
The next brightest is an 8X at 370mA
and the bright one is at 400mA.
img03117555326.jpg

img0309t.jpg

img0310i.jpg
 
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climbak said:
The amount of power you will gain by removing the window is very low. The window is 0.25mm thick and is AR coated on both sides. My guess with the bulk style coating they have on them that you would gain maybe 1%. Removing them can be much worse than the worth of an extra 1%. The 405nm diodes are packaged with dry nitrogen in the can. When you remove the window you expose them to the water vapor and some other gases in the atmosphere which degrades the diode facet very quickly. In a test I did with a PHR diode, the threshold current went up from about 30mA to roughly 37mA after 24 hours of on time at various currents. The power also dropped about 34% at 65mA. This is probably why you noticed the drop in power after a few minutes of on time. With the lens in front of the diode it will more or less seal the diode from the outside atmosphere, but the water vapor that was in there to begin with probably already did its damage so as long as the diode stays sealed there shouldn't be any more degredation. The 405 light drives the reaction so it happens quickly. There is a paper on this that I can show you if you send me a PM.
Click to expand...

ZOMG!!

The man is bak!

I can't believe you left us for so much time :cryyy:


@yobresal: Dude, thanks for taking such risks... though they indeed look amazing. Maybe the new build boasts a longer wavelength 8x, maybe 410-415nm?
 
I love taking these kinds of risks. Remember my aquaries. That one stung. I replaced it though. That is why I usually end up killing half my PHR diodes. In this case I can get to a high enough power that I don't need to push any farther.
 
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yobresal;

There are several reasons to leave the can on.

1. As Climbak mentioned, the higher energy UV light will break down smoke and other particles in the beam and eventually deposit them on the output facet.

2. The lens from me is designed to focus in conjunction with the laser diode window in place.

That is a very nice UV host collection.

We want power levels !

LarryDFW
 
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Thanks Larry. I will be keeping the windows and cans on all future diodes. This one retains the can but not the window. I will post output measurements when I get my laserbee which should provide a good idea of how much degradation has occurred based on an average projected output at 440mA current vs actual measured output.
 
I gave in and just upped my 8x from 300mA to 404mA :eg:

Those of us running at these currents should send a PM to FrancoRob so he can add this info to the 8x BR DIODES data sheet he graciously created.

I need an LPM before I can give him my mW reading... anyone close to Fountain Valley with an LPM?

mz
 
yobresal said:
HOLY CRAP! I couldn't have asked for a more thorough answer. Thank you very much for that. I really appreciate the info. It is something I often questioned when I see people "decanning" diodes. I think I will leave the window/can on for my next build. Should be done in a 10 minutes or so. Be right back.
Click to expand...

Yeah, I have seen a lot of people decanning their diodes so I felt the need to let everyone know the risks to the diode. If you see a continued drop in power from the windowless diode, could you give me a rough estimate of time on and the power drop? I only did a test with a diode in open air with no lens to block it to degrade it purposefully. It'd be interesting to see how well these modules seal the diode from the outside world.

nikokapo said:
ZOMG!!

The man is bak!

I can't believe you left us for so much time :cryyy:
Click to expand...

haha. I get on the forums from time to time. Just don't usually have the time to respond to anything most of the time. Getting a job directly working with these 405s and other lasers has made it a lot less fun to play with them at home on my own time. Still trying to convice them to buy an 8X so I can see a half watt...
 
What kind of job do you have that involves 405nm laser diode? Sounds interesting.
 
Turn it to 10kma and blast a whole through the Earth lolwut.

If anyone could kindly send me the important pics in this thread (charts mainly) it would make my christmas just that bunch better.
(For some reason my router blocks out EVERYTHING from imageshack)

Regards, Marcus
 
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