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FrozenGate by Avery

NUBM44 6W+ 450nm Laser Diode

Yep this unit was built with the clamp sink pictured above.:beer:


 





In the second video the output power is really stable in the first working minute! Never seen such stability in high power diode in an handheld device!
There are some important differences between the first and the second video? (heatsink, cells, drivers, and so on?)
 
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Minamoto Kobayashi said:
In the second video the output power is really stable in the first working minute! Never seen such stability in high power diode in an handheld device!
There are some important differences between the first and the second video? (heatsink, cells, drivers, and so on?)
Click to expand...

It says 3 element in the 1st and G2 in the 2nd. My bet is the 3 element is getting hot as it's sucking up 30% of the output and probably adding heat to the diode. Just my guess anyway.
 
Sorry, now I see the difference in the video titles :beer:
Yes, Your theory could be right: 1.3W of power loss means 1.3W transformed in heat added to an already hot barrel ...
 
The second video is beyond the resolution of the meter so it is only telling you it is above 6.6W for the first minute. It probably starts around 7.2W.:beer:
 
Minamoto Kobayashi said:
Sorry, now I see the difference in the video titles :beer:
Yes, Your theory could be right: 1.3W of power loss means 1.3W transformed in heat added to an already hot barrel ...
Click to expand...

There's no need to be sorry my friend, we are all here to share knowledge and learn.:D
 
Having deep heat sink fins is more important for high power laser diodes like the NUBM44, unless you want to live with short duty cycles. I keep seeing laser pointer heat sinks with about 1/10 the fin depth they need to have to be effective, or no fins at all, just a round chunk of metal. It is good to have a fair amount of mass to soak up the heat, but unless you have lots of surface area, the aluminum or copper cannot efficiently transfer that heat to the air. Because of this, your heat sink will continue to get hotter and hotter as you continue to use the laser.

Here's a photo showing a good ratio of mass to heat sink fin area, this is a RF 50 ohm dummy load, I have been looking into modifying one to use as a laser pointer heat sink. Most heat sink fins I see on pointers these days are mere art, just a hint of heat sink fins to make the host look cool, but they will not do much more to keep the diode cool.

100W_50_Ohm_DC_3GHz_DIN_Female.jpg

The above dummy load heat sink is an engineered heat transfer device, copy it and save yourself the trouble of the complex math involved to design an efficient heat sink, or buy a dummy load like it cheap on ebay and have it machined to fit your module and host. Heat sinks radiate heat better when black, that's why high power heat sinks are often that color.
 
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Yes You are right, but You must consider also how heavy is the "chunck of metal" You're talking about.
For example, Cypreus II XL is not so big and it has not fins, but it is all copper made and it is very long. When I power it after 1 minute the head is warm and after 2 all the item is warm with almost the same temperature distributed in all the lenght. This means that all the heat migrate rapidly from the head to the back part of the host, keeping the upper part almost cool.
 
Yes, true. That host has enough mass that it won't heat up too much for that period of time, being so long, that gives it more surface area to transfer heat to the air too, if the heat can efficiently migrate throughout the whole host, handle and all, but not all hosts are made that way. It's when the mass is distributed in more of a block shape and no fins where they can store more heat than they exchange to the air and thus have a steady temperature rise. This is all moot for those who don't operate them a long time, I tend to run my lasers a long time when I use them, so for myself I much prefer deep heat sink fins. I like a 100% duty cycle, that's the cats meow and bee's knees for me, but of course I'd never do that, batteries won't support an infinite duty cycle either, unreasonable period of time to have an unlimited duty cycle for a laser pointer, yet, then no fear of overheating your laser if your driver will take it too :)
 
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planters said:
The beam was better as well. With a 5x cylinder pair the beam at 30cm from the collimator was 7mm high and 3mm wide and at 14M the beam was 16mm high and 6mm wide.

As I posted above, my power meter is very similar to DTR's or around 5% conservative. In addition, I examined the lens he sent and it was pretty clean but, not perfect. It was in about the same condition as the G-9 that I installed for the first test.

The high power is a great finding, but the better beam is more important to me. Three of these could be knife edged to produce a 7x9mm beam with 20W of power and a PBS would allow you to produce the same beam with 40 watts!

Nice.
Click to expand...

Yes...I am pleased your optical tests agree with my results.....and actually your divergence works out to about 1.1mRad....where as my quick test gave a reading of 1.28mRad.

The take away is that this LD can be corrected....and with correction ...both the Hand Held and Projector application will benefit !!!

40 Watts of Blue ...in a 6 LD unit !!! WOW !!! :drool::drool:
 
I have just completed a 180min. continuous run with the diode DTR sent to me. The diode was driven @ 4.5 A and the output power remained stable @ 6.34 watts.

The beam size and divergence were also better than the first diode I tested.

Now my question for the members here who focus on laser pointers. I have no issue with these. I am not one of those " you only want to point it at airpl###s" or cut electrical tape. But, what about the thrill in building an incredibly powerful, desktop sized module that without 3 phase power or a water source will produce 40W of blue light? You can generate patterns with a simple scanner or effects with lumia. With this kind of power you could scan an image and burn it into a 4x8 sheet of plywood. Only a small number of the laser-show professionals around the world deploy 40 W projectors. That would hold my interest for some time.
 
That's right DTR, now I remember seeing it in I think my own thread when I was asking about them:crackup: Someone named Pman needs to cut back on his pain meds.
Did you try a comparison to running that or any other diode in that same sink and also in the 12mm one? Would be really interesting to know the actual % of improvement. So great to see such stability.
 
planters said:
I have just completed a 180min. continuous run with the diode DTR sent to me. The diode was driven @ 4.5 A and the output power remained stable @ 6.34 watts.

The beam size and divergence were also better than the first diode I tested.

Now my question for the members here who focus on laser pointers. I have no issue with these. I am not one of those " you only want to point it at airpl###s" or cut electrical tape. But, what about the thrill in building an incredibly powerful, desktop sized module that without 3 phase power or a water source will produce 40W of blue light? You can generate patterns with a simple scanner or effects with lumia. With this kind of power you could scan an image and burn it into a 4x8 sheet of plywood. Only a small number of the laser-show professionals around the world deploy 40 W projectors. That would hold my interest for some time.
Click to expand...

I have owned some of the low end lightshows with the dmx controller and the software for my laptop, but I had a lot more fun building my own gyro with 3 spinning front surface mirrors and 3 channels of speed control with pulse rate and pulse width control. In addition to all the geometric shapes, stars, flowers I also made some really wild expanding/contracting patterns when I added a 4th channel. I wish I had the means and where with all to do more, I would love to get into holography. But as my disposable funds are limited I also enjoy the simple things like burning leaves on my property and creating my own liquid sky against the trees by hand on a foggy night. My point is that some of us enjoy all aspects of this hobby, or at least as much as we can afford, and what I can't devote the time and money to doing I do enjoy learning about. I think the main thing that the pointer only people need to remember at all times is the safety of others and having respect for other people who enjoy this hobby by not becoming complacent and doing something terribly stupid.
 
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