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FrozenGate by Avery

Pioneer 12X Blu-Ray-- BDR-205

daguin said:
If that data for the BDR-203 was taken from the 8X thread, those readings were taken with an aiXiz acrylic. We need to compare them to the graph in the "mudrer" thread

http://laserpointerforums.com/f38/8x-diode-murder-fund-43993-16.html

Peace,
dave

**EDIT** I forgot about FrancoRob's graph of the 8X's. It is much better!

**EDIT** P.S. On FrancoRob's graph there are three putting out over 500mW. However, all of those are at 360mA or higher
Click to expand...

Perfect, that's a better graph,
it's showing 505mw out at 350ma.
if it had also the mw in that would be even better, but the data isn't there.

The reason is that the drivers are working at their voltage limit and the voltage could vary by a few decimal points. 1 thenth of a volt at 300ma is 30mw. IF the efficiency is 25% , that's a difference of 7 to 8mw of optical output for every thenth of a volt.

Still 505mw vs 519mw if both the current and voltage were the exactly the same, it would be a difference of 14mw which is about 2,7%

That isn't exactly statistically different, expecially if we take into account the "unknown" wattage in, or at least the voltage in.

Since different diodes have had pretty large differences in the past, like phr vs 6x vs 8x.

It's safe to assume that the diode is the same. I am the first one to hate the results but it's a fact.

Thank you Daguin for testing the diode, in the future I will be quiet. I hate breaking people's hopes and expectations.
 





Here are some more complete graphs (the "hump" on vf is due to excel's interpretation of a best-fit curve, it does not know about thresholds. I added point (0,0,0) as a common-sense point but this confuses excel somewhat... ;))

Eff = (power in over power out) against current
VF = Diode forward voltage against current
mw= Power out over current
 

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Last edited:
daguin said:
A package came toay


Opened up


Hmmmm Deja Vu
This looks very familiar . . . . . .



The sled


Now where have I seen that sled before?
Oh Yeah! In the Pioneer 8X Blu-Ray -- BDR-203!!!!!!!

The only difference I can see between the two sleds is that the beam circulaizer lens that is in front of the diode in the 203 is gone in the 205!!
Click to expand...

That COULD mean the 12x has a better aspect ratio ("rounder" beam) and does not require the circularizer!

A trait common to higher power diodes!



daguin said:
There are some differences in the drives but the sleds are the same **except for the lens right in front of the diode**
There are some VERY similar markings on the printed circuit as well.

The diodes are visually identical!!
The red diodes are the same as well.

Don't jump the gun on the 12X!!!! It may be the same diode as the one in the Pioneer 8X.

I do NOT know if I will get to testing the diode this weekend or not.

So how did the burning speed go up from the 8X to the 12X?
Click to expand...

In the 4x = 6x GB mess i explained there are TWO WAYS of reaching higher writing speeds:
1. Same sled/optics efficiency + higher power diode
2. Same diode/better sled/optics efficiency..

This was the argument i used back then, to convince Amkdeath that the diode in the 4x sled and the 6x sled CAN NOT be the same, because the sled IS.


If the sled is nearly identical, it's a GOOD indication the diode is not!
Even more so, since it's missing the beam circumsizer.. The beam circularizer is normally used to make better use of the diode's output - instead of cutting away what is not round, it is made rounder with a cube.


That does not mean that i guarantee this is a better diode, BUT!

Higher speed drives DO require higher power diodes... 12x drives say they need 300mW diodes, at least two manufacturers have a 300 or 320mW Pulsed diode which they say is for 12x drives...


Testing the diode with a PIV plot will tell much more of course.
Checking for aspect ratio and comparing it to an 8x even more.

Ith should be a bit higher and maybe the efficiency could be better...

Vf might be very important to distinguish between the two as well...



Unfortunatelly i only now saw your email, i was offline mostly, to get some important work done faster. :(



Oh, there is another option. The beam circularizer, while it is meant to make better use of the diode's output also wastes some power, due to reflective losses (present even with the best coatings) and the thickness of material the light has to pass..

IF they found a way to avoid having to use the cube, but still managed to make the beam more circular, like with an angled LCD window, it is theoretically possible they could reach higher powers with the same diode...

But if EVERYTHING in the sled is IDENTICAL, and the ONLY difference is the missing circularizer cube, chances are GOOD this diode is a higher power one!


Still, PIV testing will probably give the most answers. Since this happened 5 days ago, it was probably done already?
 
Last edited:
pullbangdead said:
Or maybe it's exactly the same, and the drive company was leaving the power turned down on the 8x so they could use the same product all the way through 2 cycles, thereby maximizing profits.
Click to expand...

If that were true, then the 8x's would have the 300mW diode turned down, which would explain how they can survive 400-500mW!

But then why use the beam correction cube in the 8x, and not in the 12x, when the cube is meant to make better use of the diode's output?
 
luxignis, i appreciate your analysis!
..of course i have to try to find faults! :-P

first, what does the voltage by itself have to do with it? i expect everyone who installed an expensive 8x diode to have measured the current with a dummy, maybe with the diode itself too. or have drlava set the current, which is pretty stable with different loads. even if the voltage would have been measured wrong, doesnt matter? we dont compare power-efficiency (electrical power in vs optical power out) here, do we?

even if the characteristics are the same (within normal variation, that is), there *must* be another reason for the wait between 8x and 12x drives. i cant believe its simple market-strategy only. one of the several drive-producers would surely have started earler to be the first, now at least two manufacturers start at the same time?

hmm, what does the manufacture-date say, dave?
i bet its pretty fresh!

then the (almost) identical sled. for me its a hint that the diode is different.. (but then theres an answer i try to see, try hard! heh)

but then, even if the diodes all came from the same box: at last they have to be cherry-picked? (ok, by now i sound whiny)
how to find out? obviously, the comprehensive 8x test has to be done.. but then, what then?

ah, igor, come on! you cant be offline or asleep now, can you? quick, someone call and alarm him! :-)

manuel
 
I am pretty convinced now that they achieved the higher burn speed by having a machine select hotter diodes (2-3%) to put in these 12Xs, combined with an innovative "vibration dampening system thus more precise burning " . What they did was pretty smart, maximize what you have, limit the losses, all of these things put together.....
 
..yes, the "turned down 12x diode in 8x sled".. they could have turned the diode up, to, say, 12x power, to save the circularizer.. then, with the losses due to the wide beam, power maybe would have been too little for actual 12x burning. then they would have used a circularizer, in the 12x sled!

if possible at all, measuring the current through the diode at actual burning 8x and 12x would give some hints. giving the diode that current outside in CW would easily tell the power. good data for comparing the two, as well as answering that question once and for all.. soldering two tiny wires between the cutted diode-wiring shouldnt be too hard? i would try that myself right now if i had a full drive here!

hmm, perhaps we should all wish that the 12x diode is all the same? 12x diodes for the price of "mislabeled" 8x drives!
hmm, maybe we should recruit some of those amazing hackers which re-write writer firmwares.. they could test and answer a lot of things, i bet!

manuel
 
LuxIgnis said:
Perfect, that's a better graph,
it's showing 505mw out at 350ma.
if it had also the mw in that would be even better, but the data isn't there.

The reason is that the drivers are working at their voltage limit and the voltage could vary by a few decimal points. 1 thenth of a volt at 300ma is 30mw. IF the efficiency is 25% , that's a difference of 7 to 8mw of optical output for every thenth of a volt.

Still 505mw vs 519mw if both the current and voltage were the exactly the same, it would be a difference of 14mw which is about 2,7%

That isn't exactly statistically different, expecially if we take into account the "unknown" wattage in, or at least the voltage in.

Since different diodes have had pretty large differences in the past, like phr vs 6x vs 8x.

It's safe to assume that the diode is the same. I am the first one to hate the results but it's a fact.

Thank you Daguin for testing the diode, in the future I will be quiet. I hate breaking people's hopes and expectations.
Click to expand...

NOT NECESSARILY.

Seriously people, let's slow down for at least a few minutes, and at least 1 more test.

Think about how these violet diodes fail, what's their failure mode? Is it COD? I seem to remember that these diodes don't roll over in power, and that they go pop at the same output power no matter the cooling/heatsinking/whatever, right? So that's COD.

So how do you fix COD, if COD is the factor that is limiting you from going higher in power in production diodes? You make hardier facets. The diode already works well, the facets are already very highly reflective (that's easy), how do you fix COD to get higher power? You do things like that AlON article that got linked a few weeks ago, you do things to make your facets more resistant to COD. You don't make the diode work any better, you make it able to withstand its own power!

Think of it like a powerful racecar. Every weekend, you go to the track, and your car always breaks down, and it always breaks down by tearing up the transmission. Now if you want to make a faster, tougher car, are you going to bother with improving the engine and getting more power? No! you're going to put a tougher transmission into it, so that the car can withstand its own power! The car won't accelerate any faster, it won't have any more torque, but it won't break when it gets to high speed/high torque.

That's what they're doing here. They didn't need to add power, because the mirrors already couldn't handle the power output. They needed tougher mirrors!

And you can easily make tougher mirrors without doing anything else to the diode.

I'm not saying anything for certain, this is just a theory. But if every single 8x diode was dying due to COD, then it makes perfect sense to simply reduce COD, and thereby increase max output power without changing anything else about the diode. Look at the charts, If you can never do above a max current, what good is it to make you differential efficiency slope steeper? It's useless. But better/tougher mirrors can increase the ceiling, without changing the slope the diode takes to get to that ceiling.

Just a theory, and my long-ass-winded way of saying to step back from the ledge, and wait until we have more data. Or heck, go buy a drive and add some more data yourself!
 
Krutz said:
luxignis, i appreciate your analysis!
..of course i have to try to find faults! :-P

first, what does the voltage by itself have to do with it? i expect everyone who installed an expensive 8x diode to have measured the current with a dummy, maybe with the diode itself too. or have drlava set the current, which is pretty stable with different loads. even if the voltage would have been measured wrong, doesnt matter? we dont compare power-efficiency (electrical power in vs optical power out) here, do we?

even if the characteristics are the same (within normal variation, that is), there *must* be another reason for the wait between 8x and 12x drives. i cant believe its simple market-strategy only. one of the several drive-producers would surely have started earler to be the first, now at least two manufacturers start at the same time?

hmm, what does the manufacture-date say, dave?
i bet its pretty fresh!

then the (almost) identical sled. for me its a hint that the diode is different.. (but then theres an answer i try to see, try hard! heh)

but then, even if the diodes all came from the same box: at last they have to be cherry-picked? (ok, by now i sound whiny)
how to find out? obviously, the comprehensive 8x test has to be done.. but then, what then?

ah, igor, come on! you cant be offline or asleep now, can you? quick, someone call and alarm him! :-)

manuel
Click to expand...

... actually my way of thinking is different from yours.
Why did only Pioneer come up with this?
if the diode was different the supplier of the diode would make it available to all manufacturers to sell more, so we'd have LGs 12x, we'd have Sony 12x etc etc.
We only have Pioneer's 12x. Plus Pioneer stated that the innovative feature of this drive was a low vibration system which made the burning more precise, minimizing power losses, therefore they could up the turning speed while burning.
If you take this information and also realyze that a 2-3% power difference can only come by "cherry-picking" these diodes (with a robot of course, not by hand), you'd come up with my same conclusion.
Why would a manufacturer spend tens of millions in research to produce a better diode, to get a 2% gain at 200mw??
It would be a terrible failure.
Just doesn't add up
 
You guys are funny LOL. Why dont you wait till more testing is done before shoving each others opinions down each others throats LOL.
 
Tech_Junkie said:
You guys are funny LOL. Why dont you wait till more testing is done before shoving each others opinions down each others throats LOL.
Click to expand...

Absolutely, more testing is needed... will buy a 8x and contribute to the testing. Now it's midnight in old Italy, I'd better get to sleep.
Arrivederci.:beer:
 
haha, i agree to all of you! techjunkie is right, slow down everyone, a bit?
lux, there are other 12x drives, i think? one other at least? the pioneer is the first one, yes. the others are not out yet, and may take a year, we cant be sure about their releasing date.. but 12x showed up in the news almost at the same time for at least two manufaturers.. (hope i'm not all off here)

pullbangdead, thats a clever idea! it would explain about everything, with no new big questions! reworking the facets would give higher power to the same die, would take quite some time after the original die/diode is out, would not change the electrical characteristics (too much). heck, perhaps it even influenced the output's beamshape, for dropping the circulizer?

*takes deep breath, pries finger from the F5 key, goes to do some kitchen-cleanup*

manuel
 
daguin said:
Who wants some data?

I use a Rkcstr driver so the lowest current is ~57mA. The test was done with a 405-G-1 lens (from Jayrob)

Pioneer BDR-205BK (12X) blu-ray

mA - mW - VF
57 --- 48 -- 4.1
100 - 125 - 4.49
150 - 198 - 4.95
200 - 281 - 5.24
250 - 356 - 5.48
300 - 443 - 5.64
350 - 519 - 5.76

That's all the farther I pushed it (utill maybe we know more?). Maybe someone with more computer savvy than me can graph this and then set a comparison to the 8X graphs

http://laserpointerforums.com/f51/pioneer-8x-blu-ray-bdr-203-a-36790-3.html

http://laserpointerforums.com/f38/8x-diode-murder-fund-43993-16.html

Peace,
dave
Click to expand...

dave did you take any temp readings??
 
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