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ArcticMyst Security by Avery

Diode better than LPC-815

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Thanks to all answers. Very comprehensive and full of ideas.
From what you tell me, not the red lasers are evolving towards 400mW. Therefore, the solution is to use a lens Meredith, perhaps modified forms Aixiz. A question about http://laserpointerforums.com/f64/f...fication-fit-aixiz-25-increase-red-46332.html ,this lens is also mounted on modular O-like? Like this? 5.6mm diode housing w/red laser glass lens [OL1845-RL] - $6.99 : Welcome to O-Like.com, Your source for laser products
Can you give me more information on using more diodes combined? What is BPS-Cube? There are affordable, I guess is an optical bench for laser diodes.
Some details about the "tech coolers" are around $ 10-20. Do you refer to cells peltier? Thanks to all, a very good input to my update.
My opinion, based on tests I have performed, using TEC's with 5.6mm diodes are as follows;
TEC's are not needed on anything under 1W.
A heat-sink with the proper mass and surface area (finned), and with good module-to-heatsink contact, (.002 under, press fit) will do an excellent job of keeping an LOC or LCC cool. Add a small fan to the enclosure if needed.
I have both an LOC and a LCC, running at 520mA and 510mA respectively.
I ran a test, using a thermocouple probe inserted through a 1mm hole in the H/S and Aixis, touching the LD, the highest rise in temperature I have recorded is 23º F, used in combination with a 4.5 CFM fan.
TEC's have a few drawbacks. Unless you are using a hermetically sealed enclosure (or a TEC designed especially for LD's IE: 10X10mm) you are going to have condensation problems. Especially using the standard "mini-fridge" ones.
A TEC designed to cool down 3-6 cubic feet, inside a 4"X6" project box will have very little heat to dissipate in comparison. The project box becomes like a ice cold Coke bottle taken into a hot room.
My early attempts at using one, ended up producing a project box dripping water like a leaky faucet.
This was in Florida,(80-90% humidity), in dryer climates this might not be problematic.
Using 5.6mm LD's, under 1W, with the proper H/S and ventilation, the use of a TEC is more troublesome due to condensation, more current draw, and up to 185º "hot" side that will melt plastic and burn the he!! out of your fingers, and seems to provide no added benefit vs. proper H/S'ing
I am sure they are exceptions and this may not apply in all applications.
 





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Well as far as tec you can regulate temp with it you only need to run it at low powers for this. i am putting one in my scanner and its going to be hooked to a small thermal probe so if the scanner starts to warm due to the encloses small size it will turn on.
Its not attachted to anything its just to cool the air in the scanner so i don't have to worry about dust or air filters.
As for a over driven red i would advise the small 1in coolers and run it at a low power. just enough to counter the 23º change. if you have an old graphics card that has one of those small heatsinks with a fan use that on the other side of the tec.
You will need to make a current driver for the tec, just like the ddl driver very simple and cheap.
 
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There are some new flat plastic red diodes with a higher rated power (f.ex from the bluray 8x and 12x drives), but little is known about them. Other than that there are red DPSS systems.

Red DPSS!?!?!

Those little plastic things are DPSS? Naw, I've never heard of that! Really? Huh...

-Tony
 
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grix was saying that those diodes with heat spreader encapsulated in plastic may have higher efficiency, efficacy, power, what-have-you. We don't know yet, forum members are testing them.

He then went on to say that other than those, your best bet would be a red DPSS system for a high-power red.
 
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I know that red DPSS lasers exist, I was just questioning that that little plastic diode has a pump diode and a crystal array. It makes no sense when diodes are cheaper to produce and are more stable than DPSS. It just seems kind of odd for a DVD drive.

-Tony
 

Grix

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Nono, the plastic one is a regular semiconductor diode.
 
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How do you know they are DPSS? There's no point if diode is available.
 

Grix

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They are DPSS; they use a Nd:YVO4 crystal lasing at 1342 nm, which is then frequency doubled.

I believe they are much cheaper and has better beam quality than red diodes at the same power?
 
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DPSS beam quality is amazing. I love my green not because it's green, but because it is a small round dot. Look ma, no wings!

edit: oops, didn't realize grix said the same thing on p2
 
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DPSS beam quality is amazing. I love my green not because it's green, but because it is a small round dot. Look ma, no wings!

edit: oops, didn't realize grix said the same thing on p2

The beam quality is excellent when it's running efficiently. However, DPSS is susceptible to mode hopping and unstable output. Take 473nm DPSS systems for example. Unstable output is normal for them. But I agree, when it works, it works beautifully. The beam diameter on my PGL-III-A is like 1.5mm at aperture. In the dark it looks like a nice clean thread of light. It amazing. My favorite wavelength is green too.

-Tony
 




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