WHY ? What made that Diode look this way?

mark-in-dallas said:

The 445nm's do not produce round beams to begin with, so the rectangular shape is normal, and the blotchiness (is that a word?) of the pattern is something that you see in all 445's, and all look slightly different, which is probably just due to how the emitter heats up and/or dissapates the light.

I could be way off base, and that's far from an educated guess, but that's what we settled on anyway. Here's a pic of the diode pattern, with a secomd diode pattern for comparison above the one that produces the blotchy characteristics.

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That's very true I was certainly taking a stab in the dark. I don't think either of use could really explain it. I certainly don't understand the material physics at the emitter level.

I've seen four or five different pattern distinctions from 445s. I've seen some similar to Mark's before, but not Dawinzi's.

FWIW, I think Mark was trying to be kind in not mentioning this, but the diode in his photo is actually from a Mosquito module I sold him. The upside, is that I know the origin, and it's nothing unique. Just a typical A145. That said, it was the most efficient diode of 24. I believe it was nearly a 1-to-1 ratio with a basic 3-element lens. Does a higher level of efficiency have the ability to change beam dynamics? (I can't say that it does in my experience)

GBD said:

InGan dies oxidize over time when exposed to oxygen (which what a window-less 445nm diode will do). Its possible this is simply corrosion and slow death of the diode and its facet.

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Nah, not really.

As far as the output pattern: I does change a bit when you vary the current, the light distributes over 3 main stripes, with the middle being the brightest by far. At higher power levels the other stripes become relatively more powerful. People have observed that the beam quality of these 445s is better at lower currents.

Mine did this as well... I was able to clean it up a little bit but it never fully went.

I had one of these blurry dots as well. Turned out that optics were plastic. Once I changed to a glass lens the output was clean multimode.

Do you live near a big transformer station or under high voltage power lines or something? And was your last post a way of informing us that the diode gave up and died?

I LPM'd mine when it was like that.. and it only reported a loss of about 60mW.

No, no powerlines at all. Right now the Beam pass a glas Lens and is looking like this. Big fat, not a thin nice shape anymore.

BShanahan14rulz said:

Do you live near a big transformer station or under high voltage power lines or something? And was your last post a way of informing us that the diode gave up and died?

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