Power Meter Calibration and Comparison

[Zom-B]

[Updated list]

Participant	Location	Has lasorz?	Paid?
Kenom	Montana	Yes, r u kiddin'?	Builder
IgorT	Slovenia	Yes, r u kiddin'?	Yes
jayrob	California	Yes, see sig	Yes
rckstr	Ohio	Yes, r u kiddin'?
DanQ	Davis, California (northern)​	more damn LAZORS than I can count​	Yes
Zom-B	Netherlands	See my sig	Yes
hydro	Sothern California	?	Yes
daguin	California	Yes, r u kiddin'?	Yes
pullbangdead	California	has lazors, too
GooeyGus	Washington st	Yes
scopeguy20	California	Yes, see sig	Yes
drlava	Cleveland	has lasorez	Yes
happytomato	Uk.	?
pseudonomen137	Texas	no Lasorz but lasers? :
muledeer	-	not participating	Yes

[edit]swapped places so this is on the new page

 

[Kenom]

As far as payments are concerned, there's only gooey and pseudo left to pay.  I got my bluray and red diodes in the mail today (hopefully the bluray diodes work since they had to be decanned because of those blasted loose windows.)  I'll be throwing these diodes into the hosts tonight and doing some preliminary tests on the diodes to see if they are going to be up to par (I had one 803t putting out 40mw at 120ma. ) and will add the drivers and psu once that's done.

rckstr, did we decide upon who was going to provide the box and such for this? I've recently come upon a flat box that is not necessarily big, but big enough to affix any customs forms (the larger is needed if shipping priority) to the box. It's roughly 6"W x 4"H x 3"D

 

[rkcstr]

I'm shipping the stuff to you (in about 15 min when I go to the PO  ) in this box, which is appx 9.75" long x 6.5" wide x 2.5" high.  The label sticking area is just under 9" long and 6.5" wide.

It has low compression foam padding with cutouts for the PSU and cables (which I was hoping would also fit the laser housing along with them).  I also drew in cutout regions according to the dimensions of the tripod pieces as well, but figured I could leave them in for you to do in case I didn't get them right.

To cut out the foam, I just cut criss-cross 1cm spaced lines in the area and then ripped it out with my fingers, which worked pretty well.

EDIT: For the pieces you have left, you may need to just cut out those traced places all the way through, make a hole, and using some of the egg-crate foam you said you had on top and bottom. The laser housing/wire holes may need cut all the way through as well to properly fit them.

Here's a pic:

 

[jayrob]

Hoping to have a better meter soon! If I get one in time, I'll just record the testing for both meters.

Help a builder get a better meter!

If anybody knows of a fair deal on a good thermal meter with digital read out, please let me know!
Jay

Never mind! Just bought this:
http://cgi.ebay.com/Coherent-Molect...ryZ73164QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Patience is not a virtue of mine.... Besides, I wanted to get one for using and calibrating during this experiment of ours!

 

[IgorT]

I got my bluray and red diodes in the mail today (hopefully the bluray diodes work since they had to be decanned because of those blasted loose windows.)

You'll be using decanned diodes for the calibration blu ray?

How do PHRs behave in the long term, when decanned? I'm asking, because i read something about inert atmosphere in the can once.

 

[pullbangdead]

It has been mentioned on here that exposing the diodes to atmosphere (oxygen, water, etc.) will "degrade" the gallium nitride in the diode. Upon asking one of the staff Ph.D researchers I work with, it is certainly not a given that that will happen, but it's not completely excluded either.

His opinion, based on previous knowledge, reading of academic literature, etc., suggests that many believe that the facet mirrors can oxidize and degrade over time, which will definitely affect the performance of the whole laser, even if the aluminum/indium/gallium nitride itself does not degrade or oxidize in any appreciable way.

I know the red diodes come with open cans and they don't see any performance degradation, but this is a completely different materials system. I think it's too new to fully know what will happen after hours of running the diode with it exposed to an oxidizing environment, but I can try to do some literature searching for the effects of atmosphere on the performance of gallium nitride lasers (it's a fairly narrow/specific topic, but maybe someone has published something).

If we're using broken can/open can, it definitely needs a thorough vetting to make sure the laser is not degrading/changing with time or with usage.

 

[Kenom]

No, I'm not using decanned diodes. they were both doa! I do have another diode here that I can use I'll just have to replace it. but given the number of diodes around it should be very easy to do. I like having them in the cans as they make them easier to insert.

 

[muledeer]

[Updated list]

Participant	Location	Has lasorz?	Paid?
Kenom	Montana	Yes, r u kiddin'?	Builder
IgorT	Slovenia	Yes, r u kiddin'?	Yes
jayrob	California	Yes, see sig	Yes
rckstr	Ohio	Yes, r u kiddin'?
DanQ	Davis, California (northern)​	more damn LAZORS than I can count​	Yes
Zom-B	Netherlands	See my sig	Yes
hydro	Sothern California	?	Yes
daguin	California	Yes, r u kiddin'?	Yes
pullbangdead	California	has lazors, too
GooeyGus	Washington st	Yes
scopeguy20	California	Yes, see sig	Yes
drlava	Cleveland	has lasorez	Yes
happytomato	Uk.	?
pseudonomen137	Texas	no Lasorz but lasers? :
muledeer	?	?

[edit]swapped places so this is on the new page

I've paid, no laser or measurement device but contributing to overall cost - money sent to Kenom

Mule

 

[daguin]

No, I'm not using decanned diodes. they were both doa! I do have another diode here that I can use I'll just have to replace it. but given the number of diodes around it should be very easy to do. I like having them in the cans as they make them easier to insert.

If you need anything. let me know.

Peace,
dave

P.S. Thanks Mule

 

[Kenom]

Well, I've made a trade with ndrew for some sleds for krytons and am waiting for him to ship them to me. he may have already but have no clue. I can't in good concience use this 803t without replacing it. So, I'll either be ordering a 803t from daedal or someone else as replacement for the diode. I really hate killing diodes.

 

[rkcstr]

Sorry to hear about the diodes... i've killed so many as well :-/

But, if you need some, I have ~6 or 7 extra 803T diodes.

Also, some pics of the PSU and driver/cables:

Kenom, notice on the heatsinks, I added some "bumpers" on the fins to avoid any shorting on the grounded case. You can remove these if you want, but I thought I'd add them just in case.

 

[rangedunits]

I want some

 

[pseudonomen137]

It has been mentioned on here that exposing the diodes to atmosphere (oxygen, water, etc.) will "degrade" the gallium nitride in the diode.  Upon asking one of the staff Ph.D researchers I work with, it is certainly not a given that that will happen, but it's not completely excluded either.  

His opinion, based on previous knowledge, reading of academic literature, etc., suggests that many believe that the facet mirrors can oxidize and degrade over time, which will definitely affect the performance of the whole laser, even if the aluminum/indium/gallium nitride itself does not degrade or oxidize in any appreciable way.

I know the red diodes come with open cans and they don't see any performance degradation, but this is a completely different materials system.  I think it's too new to fully know what will happen after hours of running the diode with it exposed to an oxidizing environment, but I can try to do some literature searching for the effects of atmosphere on the performance of gallium nitride lasers (it's a fairly narrow/specific topic, but maybe someone has published something).  

If we're using broken can/open can, it definitely needs a thorough vetting to make sure the laser is not degrading/changing with time or with usage.

Red diodes suffer the same. In AlGaS, the aluminum degrades over time, eventually causing COD - hence the 5-10k MTTF of these diodes. You'll actually see output drop over that time, but the drop is not a particularly significant amount as I recall. It only takes a small defect to start absorbing light to cause COD, so its not like it can degrade significantly before the diode dies completely. That's why InGaS 808nm pumps are more like 50-100k MTTF as they help decrease that problem.

I'm definitely no expert on the subject, but from what I've read it doesn't seem the GaN oxidation will be anything to worry about as our tests are concerned (as long as no jerk decides to leave the laser on for long periods of time for no reason)

 

[pseudonomen137]

Sure Ken, if you want I'm up for being first to verify it. I'd also like to get to see it closer towards the end of its journey though! So how bout you take $20 off of what you owe me ( ) and I get to see it and the beginning and later on in its trip. Lemme know what y'all think

 

[Kenom]

that sounds good to me pseudo.

 

[Kenom]

rckstr send me a diode if you have one extracted and I'll pay you when I get the last payment from gooey.