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PLPM4L 656

gazer101

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Oh yeah? I've got a CO2, a flashlamp-pumped YAG, a couple argon ion, and a couple helium neon, and even ostensibly several dozen DPSS lasers that emphatically disagree with you.

Moreover, if you use LED interchangeably with "laser diode", you're not being clever, you're obfuscating your message.
Some people define LED as "light emitting device," so anything that emits photons could technically be considered an LED XD (including all lasers)
 



RedCowboy

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Some people define LED as "light emitting device," so anything that emits photons could technically be considered an LED XD (including all lasers)
So a 100w incandescent tungsten filament light bulb is now a LED ?

If I fill a mason jar with June bugs and shake it until they glow is a June bug a LED ?

If I light a fart is my anal sphincter now a LED ?
 

Light superglue

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656 - this was the number that made me wonder in the first thread about this chip. If by this wavelength was meant like in Osram PLPM 450, then this thing should be red. But deep red and not as bright to human eye as multi-die 637nm package from Necsel in the link above.

Another bad thing about red lasers - they do not like temperatures above rt.
So I would not power all rows without ice-cooled set up similar to one which I made for testing NUBM31 and Osram chip in my earlier topics.

EDIT: is the lens made of glass or plastic here? Regarding the cheap price of chips you got it could be plastic. Unlike for blue lasers plastic (acrylic) lenses can be OK for reds.
 

kecked

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So a 100w incandescent tungsten filament light bulb is now a LED ?

If I fill a mason jar with June bugs and shake it until they glow is a June bug a LED ?

If I light a fart is my anal sphincter now a LED ?
You have it wrong. Light emitting DIODE not device. Tech yes a diode laser is a type of diode that emits light but no one except a deceptive eBay seller would use LED like that.
 

RedCowboy

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Are you pretending not to understand that I am making fun of " light emitting device " ?
I never actually thought my butt hole was an LED......that was a " with tongue in cheek " attempt at levity towards what gazer101 had said.
Some people define LED as "light emitting device," so anything that emits photons could technically be considered an LED XD (including all lasers)
 
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kecked

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Are you pretending not to understand that I am making fun of " light emitting device " ?
I never actually thought my butt hole was an LED......that was a " with tongue in cheek " attempt at levity towards what gazer101 had said.
Yes I fully understand you are making fun of the comment. As was I... sort of. I can see how someone might misunderstand LED on purpose to take advantage of someone. For example selling yellow leds as lasers. I see it in eBay all the time. I suppose I should have zoomed back to the original comment and tagged that.
 

styropyro

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I bought some of the arrays off of AquaticHarpy and I'm finally getting around to running some tests. These are indeed legit red laser diode arrays. It's pretty wild that AquaticHarpy was able to buy these so cheaply from an eBay auction as I haven't yet been able to find anything like this, other than paying several grand for an engineering sample.

The pinout is different than what I encountered with the nichia blue arrays, and you can see it marked in the attached picture. The first array I tested has a dead string of diodes (open circuit) but this may be my fault since I accidentally hit a couple strings with reverse polarity as I assumed the pinout was identical to the blue arrays. Looking inside at the emitter layout explains the differing pinout though.

A quick power up shows each string draws 1A at a hair above 11V. The beam is quite divergent and probably hard to tame. These are certainly a novelty but they can make an enormous amount of red light for their size.

More testing to come soon.
 

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styropyro

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Beam at 11ft gives a divergence of very roughly 25mRad. Beams are not aligned with each other well. Both the beam alignment and divergence are worse than the nichia blue LDAs
redLDA3.jpg
 

styropyro

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I measured a center wavelength of 656.3nm when ran for a quick burst at 1.5A. It's crazy how much red light this thing produces! I'm not used to so much 650nm+ light. :D Power tests will have to wait for the time being. Even though the beam is messy and divergent, the novelty of so much red laser light is a lot of fun.

redLDA2.jpg
 

kecked

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Pretty color. Be a nice torch light. Mix with blue one for tropical flamingo pink! Or to drive a beam table!
 

AquaticHarpy

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Do you think it's possible to try and collimate one of these into a more beam shape? That could make for some really, really strong red lasers
 

Light superglue

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Yes, the blue Osram MDP chip also has a similar polarity (I wrote it in the corresponding thread) but unlike in Nichia the distance bw wires is 5mm what makes it easier to do a solderless 2S2P connection of rows.

I doubt that this beams pack could be collimated as a whole, maybe each beam one by one after expansion in order to separate beams more than the diameter of collimating lenses?
Another option is what I suggested in the NUBM34 topic...maybe. But it would sure not be 13usd per piece.
 




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