DTR's Laser Shop: Diodes-Drivers-Lenses-LEDs & More

[andy_con]

this is an excellent thread DTR, keep up the good work

[absolom7691]

What is the visible difference between 515 vs 520? Can you even see a difference? It's cool that these are a bit closed to Ar range So far, I like the color of 520. If 515 is not too cyan, these will be pretty awesome.

[dkumpula]

What is the visible difference between 515 vs 520?

About 5nm. <Cough, Cough!>

Seriously, I just ordered a couple of these to test. I have some 520nm modules and a 532nm sitting on my bench currently, so I'll take some pictures side by side with the 515nm on the weekend. I can barely tell the difference between 520nm and 532nm unless I see them side-by-side, so I suspect I won't be able to tell the difference between 520nm and 515nm. My blue-green borderline perception isn't the best, but I'll try to get pictures that look reasonably accurate.

-David

[absolom7691]

[B]DTR's Laser Shop:

RGB Diode Bundle $99
BRD-209 16X 405nm Laser Diodes $45
M140 2W 445nm Laser Diodes $37
M140 1.8W 445nm Laser Diode $32
9mm 445nm Laser Diodes $54
Nichia NDB7A75 3.5W 445nm Laser Diodes $125
NUBM44 6W 445nm Laser Diode $140
Osram 1.6W PLTB450B 450nm Laser Diodes $35
Osram 120mW PL450B 450nm Laser Diodes $27
Osram 250mW PLP450 450nm Laser Diode $37
M462 462nm Laser Diode $65
Nichia NDB7675 1.4W 462nm Laser Diode $95
NUBM07E 2.9W 465nm Laser Diode $140
Osram 50mW 520nm Laser Diodes $37
Nichia NDG4216 100mW 520nm Laser Diode $60
Osram 120mW 520nm Laser Diodes $75
NDG700 700mW 520nm Laser Didoes $195
NUGM01T 1W 520nm Laser Diode $210
NDG7475 1W 520nm Laser Diodes $275
Oclaro 120mW 638 Laser Diodes $28
Oclaro 170mW 638nm Laser Diode $65
Mitsubishi 180mW 638nm Laser Diode $35
Oclaro 250mW 638nm Laser Diode $29
Mitsubishi 500mW 638 Laser Diodes $34
Oclaro 700mW 638nm Laser Diodes $32

I am loving how big this list is getting!

[dkumpula]

So I took some measurements for the new Nichia NDG4216 (100mW single mode 515nm) yesterday in comparison with the Osram PLP520-B1 (120mW multi-mode 520nm) and thought I'd share my findings.



The NDG4216 has a nearly identical beam profile to the PLP520 when corrected with the G-2 lenses that DTR sells. At 86 feet, I measured the NDG4216 at 12.5mm x 5mm with the PLP520-B1 at 13.5mm x 5mm. There was a tiny bit less noise surrounding the NDG4216, but I've seen variations from lens to lens that could easily account for that. Beam at aperture was the same 1.5mm x 4.5mm for both.

I can't tell any difference in color between 515nm and 520nm, but 532nm is obviously more yellow as we all know.

My experience with the PLP520-B1 has been less than great when pushing them beyond their stated limits, so a potentially more resilient alternative is most welcome. I've damaged 6 of the PLP520s thus far including one today.

I haven't pushed the NDG4216, but I easily got it to 150mw and stable with the G2 lens and plan to leave it there to see how it holds up under normal use.

DTR is selling the new Nichia NDG4216 for 20% less than the PLP520-B1, so baring any future bad experiences with the NDG4216, I'll start pairing these for 300mW of single mode green. In fact, the only downside I see with the NDG4216 so far is that its a 3.8mm as opposed to the 5.6mm. I find my aging eyes and clumsy monkey fingers challenged when soldering the tiny leads coming off these 3.8mm diodes.

Just my $0.02 . .

-David

[JohnYayas]

So I took some measurements for the new Nichia NDG4216 (100mW single mode 515nm) yesterday in comparison with the Osram PLP520-B1 (120mW multi-mode 520nm) and thought I'd share my findings.



The NDG4216 has a nearly identical beam profile to the PLP520 when corrected with the G-2 lenses that DTR sells. At 86 feet, I measured the NDG4216 at 12.5mm x 5mm with the PLP520-B1 at 13.5mm x 5mm. There was a tiny bit less noise surrounding the NDG4216, but I've seen variations from lens to lens that could easily account for that. Beam at aperture was the same 1.5mm x 4.5mm for both.

I can't tell any difference in color between 515nm and 520nm, but 532nm is obviously more yellow as we all know.

My experience with the PLP520-B1 has been less than great when pushing them beyond their stated limits, so a potentially more resilient alternative is most welcome. I've damaged 6 of the PLP520s thus far including one today.

I haven't pushed the NDG4216, but I easily got it to 150mw and stable with the G2 lens and plan to leave it there to see how it holds up under normal use.

DTR is selling the new Nichia NDG4216 for 20% less than the PLP520-B1, so baring any future bad experiences with the NDG4216, I'll start pairing these for 300mW of single mode green. In fact, the only downside I see with the NDG4216 so far is that its a 3.8mm as opposed to the 5.6mm. I find my aging eyes and clumsy monkey fingers challenged when soldering the tiny leads coming off these 3.8mm diodes.

Just my $0.02 . .

-David

I can't thank you enough for this post.

[absolom7691]

This is good information to have as it seems like the new Nichias are more robust, slightly better beam and cheaper. Thank you, David for being the guinea pig!

[dkumpula]

Happy to help, guys. Damaging the PLP520s was getting old. I don't recall making one of those an LED, but I've seen their outputs drop by more than half with the same current over time.

Interestingly, at least the older NDG4216 which was a 5.6mm 80mW rated diode advertised it had a zener diode with one of the data sheets noting that it was intended to help protect it from static electricity (not just reverse voltage). I can't seem to find that datasheet at the moment, but I don't see any such references on the 100mW 3.8mm can version.

Speaking of reverse voltage, the new NDG4216 datasheet does not tell you which pins are which. There are three, the middle-ish being the case. The case pin is attached to the base of the diode so its easy to identify. If you are looking at the bottom of the diode with the case bin oriented so it is at the bottom, the anode is the pin on the right and the cathode is the pin on the left. I would attach a picture, but mine are already installed. I believe this pin layout is fairly common, but thought I'd mention just in case . . .

[JohnYayas]

What were you doing to damage the diodes? Was it avoidable things like incorrect wiring and over current or are they just really sensitive to static, back reflections, etc?

[dkumpula]

What were you doing to damage the diodes? Was it avoidable things like incorrect wiring and over current or are they just really sensitive to static, back reflections, etc?

All I did was drive them above their spec'd maximum power. They'll handle more in the short term, but they lose power over time. At first I thought it was issues with the drivers spiking or static electricity, but I've seen it using several of our more trusted drivers and Lasorbs didn't help the issue. (Static isn't generally a problem in the Carolinas as the humidity levels are usually registering in the "swampy" range.)

Generally everything looks hunky-dory with the diode set to a level that stably produces 150-180mW and I come back to the projector after a 3-6 months (with little use) and its doing 80-120mW (or less) with most of the loss occurring on the bottom-end like it fried a bond wire or something. Although laser diodes typically degrade over time and take additional current to produce the same output, the PLP520s seem especially sensitive. In my case, increasing current did little to increase the output. Oh, and yes I believe cooling has always been what I would think to be as more than adequate considering how much (or little) I was pushing them, although increased use of TEC couldn't hurt.

I'm hoping the new NDG4216s are going to prove to be more resilient as losing $75 x 6+ is starting to smart a little.

-David