GB: 1W 520nm diode information/giveaway

[CDBEAM777]

I had a similar idea, but with cylindrical lens'. The anamorphics would be hard to align to get the beam coming out the center of the host.

OK...We can go with Cylinderical lenses. No Problem...See the attached drawing.." Green Extreme CL 1 "

As I have had no experience with the optical characteristics of the NDG-7475...I do not know the distances from LD =====> Cylinderial Lenses...or the separation from lens to lens. I DO know that these distances MUST be spot on for the lenses to do good correction....so in this regard...using Cylinderical lenses will be more demanding.

SOoooo...yes...the beam output using the Anamorphic Prism's will be a bit off center from the HH centerline. To me....that is not an issue....as long as the beam is parallel with the HH centerline...that is what I demand. The alignment of the Anamorphic Prisms is MUCH easier than Cylinderical lenses !!!

Anyway....If correction is needed....we have a few ways to go....and both these options will correct a line into a spot ( Square )....so that is good !! Now....we wait for mass production to drive the unit cost down !!

CDBEAM=======>:beer:

 

[shokkunlasers]

ARG, how low can you go with temperature for temp testing?

I want to get super cool, down to the negative Celsius. If we can get under 515, or even under 510, that'd be spectacular.

The colorshift could be interesting but IMO that's not sth I want to test a new expensive diode
If you want to see some cool 510 nm try the single mode osram.
It's much easier to cool than such a powerful diode and in case of death It's 70$ not 700 $:beer:

 

[DJNY]

The colorshift could be interesting but IMO that's not sth I want to test a new expensive diode
If you want to see some cool 510 nm try the single mode osram.
It's much easier to cool than such a powerful diode and in case of death It's 70$ not 700 $:beer:

It isn´t risky to cool down a diode equipped with the right tools :can:

I´m too very interested in the possible wavelength shift (with a TEC setup f.e.). The closer to 500nm, the better :beer:

 

[ZRaffleticket]

^ Agreed.

Typically its heat that kills diodes. Or water.

 

[Smeerworst]

liquid nitrogen anyone ?

 

[ARG]

ARG, how low can you go with temperature for temp testing?

I can get it to 0, but at 10C condensation becomes an issue.

 

[Shakenawake]

the solution is clear. perform the test in a vacuum, where no moisture can condense:na:

 

[bloompyle]

liquid nitrogen anyone ?

Don't tempt me, this thought has come to my mind several times now. LN2 hose cooled Cu heatsink.

It isn´t risky to cool down a diode equipped with the right tools :can:

I´m too very interested in the possible wavelength shift (with a TEC setup f.e.). The closer to 500nm, the better :beer:

Personally, I plan to take one of the 120mW diodes down to -60C with a couple of 400W TECs. I don't have a fancy spectro though, just my monochromater, and before I use that, I'll need to pick up a 1% optical pick off.

the solution is clear. perform the test in a vacuum, where no moisture can condense:na:

Or you could use a desiccant to absorb moisture, and seal the laser up with said desiccant. That's basically what I plan to do.

 

[shokkunlasers]

It isn´t risky to cool down a diode equipped with the right tools :can:

I´m too very interested in the possible wavelength shift (with a TEC setup f.e.). The closer to 500nm, the better :beer:

Driving it outside of the datasheet temperature ranges is IMO also dangerous.

Just because red laser diodes lase even at 100K
and shift up to 30 nm you can't apply that for all other diodes!:thinking:

Our famous 9mm 450nm diode for example doesn't shift much and randomly dies below 200K

Ok generally they don't die just because you cool them but you need a sealed dry chamber and at least 200W TEC to reach 260K if ARG has all this we could try it.

I would still say that anybody should try a cheaper 520nm diode first which is also easier to cool.
When you have tested that you can more or less predict what will happen with a more powerful diode with roughly the same chemistry

That's how I think about this but of course it's not my diode so if you all are interested in cryogenic tests atm I'll agree to that.

p.s. If anybody already tested the pl520 or even the plp520 please share your results with us

 

[DJNY]

No one was taking about such extreme operating temperatures like the 100K / -170°C or the 200K / -70°C you mentioned.

But even cooling them down to 5°C should give a nice shift in wavelength according to the datasheet.

 

[bloompyle]

I guess I'm the only one here crazy enough to be completely comfortable with taking a 520 down to -60C, and lower if I can find a TEC that'll do it.

Also, nobody is saying that the diode will go down to 500, just trying to get as close to it as possible. It'll likely only go down to ~515 at 5C, if the PL520 is anything like this one. From 20C, to 5C, it only dropped about 0.5-1.0nm at the same current. That's the only reason why I am going so far down.

Also, Shokkun, for someone so concerned about staying within parameters, it's a bit ironic that you didn't want to be conservative with the current testing, but temperature well within the datasheet specs, is "dangerous".

No we won't do a "kill test" but also we won't be as conservative as the guy on PL he just sticked to the datasheet current ARG will make an efficiency graph and a power graph beyond those currents and will stop when he's at the highest point of that curve or becomes unstable.
Maybe it dies during that but if so it's not that hard.

Care to explain this logic? As I am having difficulty following.

As far as testing of the PL520, ARG did some very conclusive tests on two diodes, we all funded a "murder fund". See here.

 

[shokkunlasers]

No one was taking about such extreme operating temperatures like the 100K / -170°C or the 200K / -70°C you mentioned.

But even cooling them down to 5°C should give a nice shift in wavelength according to the datasheet.

Sorry than I misunderstood you guys 5C is in the datasheet range and so safe to do.
I would also like to see such a test
But a sealed or constantly N2 pumped is still needed to avoid condensation. :beer:

Just thought about lower temps because that liquid nitrogen discusion

I'm also looking forward to your tests bloompyle

 

[ARG]

Sent the money to DTR, diode should be on the way soon

 

[NightExplorer96]

Sent the money to DTR, diode should be on the way soon

Sooo...I see the diode is now on the way huh?

I hope for all that donated the best of luck, and hope it arrives soon and ready to go, it sure will be amazing to see it in action :wave:

-Alex

 

[ZRaffleticket]

op:

 

[ricktrent4]

has DTR not done a test or video yet on a LPM if so I have not seen one.
Is there a video out?

Sent the money to DTR, diode should be on the way soon