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445nm De-canning, Macro-shooting target practise

Eudaimonium

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Hi all'ya folks, well some of you may know that my very first 445nm diode died on me at 1A (it was written in the stars, I guess :( ), so today I tried to decann it and take some pics while I'm at it.

So, starting off with razor knife cuttings on the side, followed by side-cutter rimming, and finally, the can was cut... but...





Damn! Guts every where! (Traveller, I seem to have found my glue holding the diode window... )

Some close ups:









Pics were taken without any additional lens between camera and diode.

These had one small magnifier lens placed, to better get the "zoom" effect, but they lack proper focusing and quality because, as mentioned, camera lens cast shadow on the diode and all together with additional lens has very small space (of diode) that is properly focused, the rest of image is very much distorted...
















So as you can see, I managed to totally ruin the poor diode, you can see on pics that the crystal is missing as well as a portion of it's base...



Best pic of the crystal that I could take , manual focusing used, and it's really hard to see in such small parts if it's properly focused or not.

This is the diode next to crystal and a portion of the base:


These last two photos are not exactly even worth posting, but heck, just for future reference - don't decan 445nm diodes ;D

Next, I'll what can it be done with some artificial light source and a bit longer exposure with lower ISO, maybe I can get better quality shots with that, but , without any aditional tricks and workarounds I believe this is the apsolute best I can achieve with my current equipement...
Could be wrong though.

Let me know what you guys think and what pic do you think turned out best.
 

Byrnz93

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The laserist in me was cringing when I saw the first picture :(

Anyway, nice pictures, it's interesting to see what is actually in these diodes.
 

Autist

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I am sorry for your loss. :(

Good pictures.

Does it have three emitters, and that is why it is multimode ?

best regards

David
 

Eudaimonium

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The laserist in me was cringing when I saw the first picture :(

Anyway, nice pictures, it's interesting to see what is actually in these diodes.
LOL, well it died on me on 1A, and it shouldn't ... Might as well give it back to her!

@Autist, no, it is a single emitter but the output is very elongated, resembles a line and not a dot, I think ReNNo had a very good pic of raw output from the diode.

@TTerbo, don't worry about it ;)
 

Prototype

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@Autist, no, it is a single emitter but the output is very elongated, resembles a line and not a dot, I think ReNNo had a very good pic of raw output from the diode.
It's elongated because it is multimode, I don't know of any single emitter laser die capable of creating >500mW of power.

Ontopic: Nice macro pics with no external lens...my camera doesn't even come close to that quality. Oddly enough my 2mp cellphone camera with a small external lens takes incredible closeups. Also, good decanning job, I've got more than a few smashed diodes here that met an untimely demise from my attempts.
 
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Anyone has the guts to decan a working unit so see if there's any raw power improvement? ;)
- Robert
 

Eudaimonium

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It's elongated because it is multimode, I don't know of any single emitter laser die capable of creating >500mW of power.

Ontopic: Nice macro pics with no external lens...my camera doesn't even come close to that quality. Oddly enough my 2mp cellphone camera with a small external lens takes incredible closeups. Also, good decanning job, I've got more than a few smashed diodes here that met an untimely demise from my attempts.
It is multimode, but single emitter - I believe there was a discussion about it somewhere.
IR 808nm emitters can go to about 1.3W each, 10 of them forming very powerful diode bars. And this is not too far away.

Good decanning? You are kidding me, I managed to completely destroy the emitter and it's base, otherwise I would MAYBE be able to push the severed wires against the brass case and MAYBE even get a few photons from the diode.

Not exactly a good decanning , if you ask me :cryyy:

Anyone has the guts to decan a working unit so see if there's any raw power improvement? ;)
- Robert
For unmeasureable increase in power, risking to utterly destroy a beautiful diode is simply not worth it, the little window is designed for apsolute maximum transmissivness, at these power levels and densities, it would melt if it blocked only a few percent of light, so ... :D No I don't think you gonna find andybody that crazy :crackup:

EDIT: @ Trevor, thanks! You can even see how the crystal is hanging on the remains of wires, with it's blue facet... ahh cr*p now I'm depressed again :crackup:
 
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Benm

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Its interesting to see that they used 3 bond wires on each side - these things were obviously built to take some serious currents. The number of bond wires doenst have anything to do with singlemode vs multimode, they are just required to carry the current. A few thin ones provide lower impedance then one big one, which is a good thing for fast modulation (as in scanning TV projection).

As for decanning it to gain power: It will not be worth the effort. By the looks of it, the output window is AR coated for 445, and you wouldn't gain more than one percent for a very dangerous procedure. Running it 1% harder would be a safer choice ;)
 

Hemlock_Mike

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Good photos in spite of your lens!! Thanks.
Several of us have exceeded 1 Amp and the diode survived. Extra bonding wires help explain that.
My big question is "Why do I seem to see several facits across this die? This may be the first insight to this diode's wide output.

Good work.... Sorry for your diode.

HMike
 
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The one in my labby shown on youtube has a decanned diode, it was decanned because some crap fried on the window. I used a professional decanning tool made by Thor labs to do the procedure. using the tool is as streightforward as using a pipe cutter, set it and cut. The only other reason to decan a diode is to remove the window's inter-modulation type effects for holographic use.

It had two sets of 3x .2 thou gold wire bonds, each bond is good for about 700ma to 1A depending on composition, so 2A is the max electrical loading for long term reliability FOR THE BONDS. The diode is mounted on a polycrystaline diamond heat spreader on a tungsten copper planchet that was bonded to an invar baseplate. Why they didn't use copper for the baseplate is beyond me, these diodes should had the absolute best heat sinking possible.

The AR windows on these diodes are very well made, you only get about 8mw loss at a full watt of power. So unless something burns on the window don't decan it.
 

DJZ

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Hi all, I had one of these diodes fail on me as well, at about 950mA. In talking with some folks about it, we suspect the failure was due to back reflection, I guess we'll never really know for sure. Anyway, I "decanned" the diode and took some close up pics. The diode would still lase if I cranked the current up to around 1.5 to 2A, but it would only put out about 10-15mW.
 

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