G71 vs P73

[planters]

There are long threads on each of these diodes. However, as the price of of both drops with the G71 @ $40 and the P73 now at $90, is there a consensus on the relative power output and just as importantly the divergence through identical optics?

I am finishing a quad with the G71s and because I will be running it rather hard I'm thinking about phasing in the P73 diodes as replacements are needed, but this could take some time(hopefully).

[CDBEAM]

Optically....the P73 is equal to the G71. NO trade-off there.

Slope efficiency wise.....P73- .89mW/1mA..........G71- .72mW/1mA

in my experience the P73 will output 715mW at 800mA ( Max rated current ) with no TE.

We need MANY data points to establish any meaningful profile. Good Luck....But...CAN YOU EAT IT ??????

BEAM

[planters]

Optically....the P73 is equal to the G71. NO trade-off there.

Do you have a source for this? It's my understanding that theP73's emitter is 50% wider; 100um vs mid 60's for the G71. I can't find the reference (hence the post) that someone had mentioned that the P73's divergence was "somewhat" worse. This makes sense. Also, if you look at the spec sheet the raw divergence of the P73 is higher.

Slope efficiency wise.....P73- .89mW/1mA..........G71- .72mW/1mA

The improved slope efficiency is also good and if the P73 is simply a wider clone of the G71 this could derive from the lower heat rise at the junction (wider and so lower current density). As I showed before these things are very heat sensitive.

[polishedball]

The emitter is wider on a P73.

LPF has some good raw measurements if you wanna go searching.

[CDBEAM]

The source....well..... "Le eyeballs du le CDBEAM"....See pic for new product being considered by TLabs !!! haha

The corrected P73 can acheive less than 1mRad... with a nearfield of approx 4mm....I measure the same for the G71.....so...as far as I have compared the two...side by side...when corrected with a 2.0mm fL collimination lens and 6X cylinderical lenses....they are equal !!

Yes....I know the emitter geometry of the P73 has been measured to be greater than that of the G71 !!! But if they BOTH can be corrected....then....to me....the P73 is the clear choice !!

Le BEAM

[andy_con]

remember this thread chaps

http://www.photonlexicon.com/forums/...Quantification

[planters]

The corrected P73 can acheive less than 1mRad... with a nearfield of approx 4mm....I measure the same for the G71

That's good enough for me. If you see the same divergence then maybe the higher raw divergence seen with the diode is removed by a slightly different lens spacing. Whatever... Then I have every reason to drive these hard because as they die there are better ones waiting. This is another good reason for these individually driven diodes rather than series or parallel installations where this upgrade by attrition would be less convenient.

remember this thread chaps

Yes I do and I had checked it out, but the statement by CDBEAM is the additional piece missing. Now that I believe that the P73 is going to be worth it, I am going to go ahead and order a couple and do one of my cryo tests to see how it compares on this front as well.

[CDBEAM]

See pic....Another BEAMTOON....no extra charge !!! Fire those G71's up !!!

Errr...yes...it seems as though the optics used can correct both the G71 and the P73.....and I really do not care if the geometry of the lattice is in the shape/size of a dog turd....the optics correct it !!

Any others have imput on this topic !!! Verification iz a goo D ting !!!

BEAM OUT

[swamidog]

ahh.. forbidden planet. one of my favorite movies.

See pic....Another BEAMTOON....no extra charge !!! Fire those G71's up !!!

Errr...yes...it seems as though the optics used can correct both the G71 and the P73.....and I really do not care if the geometry of the lattice is in the shape/size of a dog turd....the optics correct it !!

Any others have imput on this topic !!! Verification iz a goo D ting !!!

BEAM OUT

[CDBEAM]

Ah YES...Mr SD !!! Forbidden Planet was and remains the BEST CLASSIC SF EVER MADE....It has ALL the classic elements.....and was decades ahead of it's time !!!! And yet....so many know NOTHING of it....You just get that " Deer in da headlights " look when you reference the movie !!! Yikes..." Rome rots from within "

Ah well BEAM OUT