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8x BR DIODES

LarryDFW

LarryDFW

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yobresal;

The Blu-Ray diodes project an asymmetrical pattern.

It would take two lenses to correct that pattern,

and two lenses would double the losses of the lens.

Not justified for the increased investment (about 50% for AR coated).

The Aixiz 405 lens has ~20% loss ..

vs. Hi-Power lens ~3.5% loss.

LarryDFW
 
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bryce007

bryce007

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yobresal said:
I do enjoy the additional output that your and Jayrob's lenses provide but at the same time I really wish they appearance of the spot would be as nice as the Aixiz 405 glass lens. Do you think there is any possibilty of a similar high efficiency lens with a nice clean spot coming out soon? or is that something that is inherent with the process of achieving high efficeincy output?
Click to expand...

Igor's lens is a little less efficient, but has a nicer projection. Hopefully we'll see a GB for them soon. I feel the same way you do.
 
MISTERWILLING

MISTERWILLING

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Add me back up, I have a LG 8x at 400mA in custom host using flexv4 with larrydfw lens at 505mW
 
X

x101xtreme

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I've increased the current on mine from 330mA to 400mA. It is now 500mW. Please update the chart when you get the chance.
 
pseudolobster

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I think I've finally encountered the mythical "8x degradation" :cryyy:

I swear my whitefusion kit is cursed.

Has anyone had any luck fixing this? I'm not sure decanning it will help, I've looked at the diode window under magnification and I see no dirt or anything.

Bah! That's it! I'm not buying a replacement until 16x BR drives are available and cheap.

 
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buster7467

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I just had a new PHR diode look like that after only 15 minutes of use. Thanks for posting the pic. Now i know what degradation of a diode looks like. When mine did it, I really did not know what i was seeing. With this being my first laser and all. How many hours of use is on that diode?
 
pseudolobster

pseudolobster

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MISTERWILLING said:
Yeah I saw the same thing, heres my thread with pics of the same dark ring http://laserpointerforums.com/f38/8x-diode-degradation-42088.html
Click to expand...

I was looking for that thread... couldn't find it for some reason.

Poo. I don't suppose there's any fix for this, is there?

I just can't get a break with this whitefusion kit... So far it's taken out two LOC's, a PHR, a SF-AW210, a rayfoss 150mW green, and now this.... Not to mention I've gone through a half dozen regulators and two square feet of acrylic.

Never before has milled aluminum caused me so much grief. I'm not a superstitious person, but I swear this object is cursed.
 
Meatball

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Degradation means the die is changing... chemically. There is no reversing it unless you know how to grow your own Gallium Nitride crystals...
 
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Slipstream

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Larry

How does the acrylic lens do it without the 2 lenses ?



LarryDFW said:
yobresal;

The Blu-Ray diodes project an asymmetrical pattern.

It would take two lenses to correct that pattern,

and two lenses would double the losses of the lens.

Not justified for the increased investment (about 50% for AR coated).

The Aixiz 405 lens has ~20% loss ..

vs. Hi-Power lens ~3.5% loss.

LarryDFW
Click to expand...
 
pullbangdead

pullbangdead

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Slipstream said:
Larry

How does the acrylic lens do it without the 2 lenses ?
Click to expand...

If a single element is projecting a completely round beam from an elliptical laser diode far field pattern, then it is most likely just chopping off part of the light via an aperture, eg a smaller hole that chops off the ends of the ellipse.
 
LarryDFW

LarryDFW

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Slipstream;

pullbangdead is correct.

It just chops off everything but the center beam.

That is why it also loses so much power.

Larry
 
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Slipstream

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OH , but it doesnt do that with a opened back..

or is that not even the point. the actual lens is doing the chopping ??
 
pullbangdead

pullbangdead

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The lens isn't big enough (or isn't close enough, if you want to look at it that way) to collect all the light. It's just the shape of the housing/lens nut. The light diverges really fast from a diode because the optical mode in the vertical direction (and in the horizontal direction, but not as bad as in the vertical direction) is so small, so the light as already spread out larger than the size of the lens before it gets to the lens.

The hole in the back of the nut is one aperture, but the lens nut as a whole it still an aperture in this case, because the divergence is so fast and the lens is so far from the diode. It's not a function or property of the lens per say, other than that the lens is too small or too far from the diode to collect all the light in the long direction of the ellipse.
 
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