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FrozenGate by Avery

445nm diode MURDER thread

  • Thread starter Thread starter Deleted member 8382
  • Start date Start date
Dont hold your breath. No word from Wicked for quite a while now. They have a habit of reneging on there promises.
 





Tech_Junkie said:
Dont hold your breath. No word from Wicked for quite a while now. They have a habit of reneging on there promises.
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Oh right I forgot it, I´m interested if I ever get my 250mW greenie in the silver Sonar host.

Ok got it, I will definitely notify you once its ready.

Steve
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:toilet:
 
Those have already read it on the vets section. I made the thread there to avoid spam. You'll get into the vets section as soon as you reach 1000 posts, no need to spam to get there.
 
DJNY said:
I know Albert, it was just a joke.
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oh, okay.

Sorry then. You know, without smilies sometimes it's hard to get the sarcasm, especially when English is not your native language ;)
 
i for one am really looking forward to see the results of this murder experiment. I hope WL doesn't back out from the supplying of the diodes...
 
It would be awesome if you could get an output of 1500mw and a lifespan of 1000hours.
I'd rather have that than 950mw 5000hours.
 
daguin said:
You missed my main point. You will NEVER get the kind of "confident" knowledge you are requiring, from only two or even four diodes. This is the "false" sense of confidence I talked about. Diodes are too inconsistent for that to work.

The following is going to be a MAJOR over-simplification

To discover where they will run a certain diode, manufacturers/researchers run MANY diodes at the same current. They look for the point where 50% of the diodes fail after the desired lifetime. When they reach that point (50% fail) they record it. Since the diodes in the projector were running at ~650mW and the projector is "rated" for 10,000 hours, it is probable that at 650mW about half of the diodes will be dead at 10,000 hours of use.

Understanding the way diodes are rated and the sometimes exgtreme variability in them, how can seeing that two diodes ran at any length of time at any current will assure you that any other diode will run for that time at that current. What if yours were ones that would run longer than "rated"? What if they were ones that would run shorter than "rated"? What if you got one of each?

Even IgorT's 12X experiment exposes the problems inherent in this kind of "research." Before IgorT got a 12X to run at the desired current, TWO OF THEM FAILED AT LOWER CURRENTS! However, instead of accepting this limit, we and he kept trying. We finally got one that acted the way we wanted and all breathed a sigh of relief that we had finally gotten a diode that was not defective. People now jumped on the higher "safe" current as proven by IgorT's testing. This despite the "fact" that 2/3 of the diodes tested failed well below the succesful one.

So how many diodes do we need to kill? At what current should we run them? How many hours of life at a given current will be acceptable? What good is "killing them" at all? We will know at what current those particular diodes failed after a given number of hours. However, what will that tell me about MY diode?

Peace,
dave
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I think CASIO has a 3yr, 6K HOUR warranty on the "lamp"
see warranty.

also diode manufacturers use a TEC set to X.XX deg C and monitor the current of the diodes at XXXmW. They look at trends in increases of current to make the Weibel plots, and predict lieftimes.
I have some reflections on using diodes at 2X power rating (2X current), and increases in temperate from on reliable Japan manufacturer. I can review that an makle a post.

Dave has many valid points. I have sold diodes to industrial users for 13 years, and used them for even longer. Now granted, my customers don't push diodes to 2X the CW ratings, they are utilized in a conservative way. I usually say forum members use a diode in CW mode at the pulsed rating (about 2X the data sheet rated power).
I have some data for low powered red diodes where operating current is monitored, and commented on right on the MTTF data page.
If you see the data sheet at my web site for the SANYO DL-LS5017 it is 11 pages long. It has previosuly Confidential information from the 405nm Japan factory. About 6 years ago, one needed an NDA signed and approved from SANYO just to get the data sheet!
It does have valuable information on production of 405nm for anyone who wants to look at it, although it's years old and only for a 60mW CW diode. It does have some plots that are still relevant. Anyway, it also shows that the tests for lifetime, and distribution data (results from actual diode measurements, as oppaosed to data "typical" data sheet numbers), uses an number of diodes at N=355.
So who will step in so we can test 300+ diodes??
LOL

Will
 
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