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gonna try a 375nm pointer build...

Alaskan

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Rare as hens teeth, I agree, I bet there isn't another one. Good find on ebay!
 



styropyro

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The flexdrive just can't quite crank the voltage high enough. :( Options now include a microboost with a host that doesn't complete the circuit, a linear driver and Li-ions (yuck!), or a homemade boost driver. I have the parts around to make a step up driver, but I don't have a scope to see if the output is super noisy or not. Guess I'll start off by seeing if I have some casing isolated hosts that aren't giant flashlights.

Edit: Maybe I can get it to work with a minisabre v2?? I love those hosts, but the thread with pics on the construction got wiped with the photobucket BS, so I'll have to find out myself if I can get it to work.

That will be one exceptionally rare pointer---probably the only one.
Good luck--looking forward to it happening---be careful.
I'm nearly certain this will be the first UV laser pointer ever built! I only have one shot though, and every time I have to solder to that laser diode I get very uneasy!!
 
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WizardG

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...every time I have to solder to that laser diode I get very uneasy!!

Conductive epoxy then?

Good luck! We'll be watching :pop:
 
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ElectricPlasma

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Nicely done Styro, nice score on that diode. Makes for a unique pointer. Excited to see the final product of your efforts :D

BTW - best to save the alcohol for the optics :p
 

Alaskan

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Now I'm looking on ebay for a UV diode too!
 

Hap

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Is 375nm long enough of a wavelength not to cause any health concerns to us? This question is for the future, when these diodes will cost $5 on eBay lol.

Seriously though, I know 375nm is UV-A but still....

-Alex
 

diachi

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Is 375nm long enough of a wavelength not to cause any health concerns to us? This question is for the future, when these diodes will cost $5 on eBay lol.

Seriously though, I know 375nm is UV-A but still....

-Alex
Long term exposure to high intensity UV-A light probably wouldn't be great for your eyes, but otherwise it should be fine. UV-A is non-ionizing and as a result non-carcinogenic.
 

Hap

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Long term exposure to high intensity UV-A light probably wouldn't be great for your eyes, but otherwise it should be fine. UV-A is non-ionizing and as a result non-carcinogenic.
Thank you diachi :thanks:

-Alex
 

styropyro

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You can't ionize any atoms in tne ground state till a bit over 300nm. So 375nm is not ionizing radiation which is the most harmful. Still though, 375nm is in a range where it has the very real ability of promoting electrons to high energy molecular orbitals, which can initiate chemical reactions that wouldn't occur on their own. So in theory there still is a risk, but IMO you would be much dumber to step into a tanning booth than pointing this at your arm.
 

Hap

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You can't ionize any atoms in tne ground state till a bit over 300nm. So 375nm is not ionizing radiation which is the most harmful. Still though, 375nm is in a range where it has the very real ability of promoting electrons to high energy molecular orbitals, which can initiate chemical reactions that wouldn't occur on their own. So in theory there still is a risk, but IMO you would be much dumber to step into a tanning booth than pointing this at your arm.
Got it! Anything <300nm though is uber-dangerous territory then, right?

-Alex
 

diachi

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Got it! Anything <300nm though is uber-dangerous territory then, right?

-Alex

Depends on how much exposure you receive. :beer: X-rays are <300nm (0.01nm-10nm), but you can have them shot directly at your head during a dentists visit. Just depends on the intensity/duration of exposure.

Edit: Added typical wavelength range for X-rays. I should also add, area of exposure makes a difference too, some tissues are more sensitive to ionizing radiation than others or absorb them differently. See: Absorbed Dose/Equivalent Dose.
 
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Hap

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Depends on how much exposure you receive. :beer: X-rays are <300nm, but you can have them shot directly at your head during a dentists visit. Just depends on the intensity/duration of exposure.
Touche. :thinking:

-Alex
 

styropyro

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I've sacrificed two of my handheld lasers so far (one for no reason actually) but I think I have a host that will work. I'm going to have to electrically isolate the module with electrical tape or possibly thermal pads. Not an ideal method, but this is a low power diode so I don't see heat becoming an issue.
 

Encap

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Got it! Anything <300nm though is uber-dangerous territory then, right?

-Alex
"The electromagnetic spectrum of ultraviolet radiation (UVR), defined most broadly as 10–400 nanometers, can be subdivided into a number of ranges recommended by the ISO standard ISO-21348"
UV A, UV B, UV C and several more all the way to Extreme UV/10nm
See chart here: https://en.wikipedia.org/wiki/Ultraviolet

375nm diodes will never be $5 on ebay probably the current price is as good as it will get--time is never a price determining/driving factor for laser diodes beyond an initial 6 months to a year of production ramp up for a customer. Large scale use and demand is a lower price determining factor --as in laser projectors. If there is little or no use/demand then cost will be $$$$.

Styo lucked out at $80 even for a used one with a chance that it would be DOA

*ichia appears to be the first company to announce the commercial availability of 375nm UV laser diodes back in 2002--15 years ago see: https://compoundsemiconductor.net/article/82022/Nichia_Introduces_UV_Laser_And_365_Nm_LED%7BfeatureExtra%7D

"Direct UV-emitting laser diodes are available at 375 nm. UV diode lasers have been demonstrated using Ce:LiSAF crystals (cerium-doped lithium strontium aluminum fluoride), a process developed in the 1990s at Lawrence Livermore National Laboratory. Wavelengths shorter than 325 nm are commercially generated in diode-pumped solid-state lasers. Ultraviolet lasers can also be made by applying frequency conversion to lower-frequency lasers."
See: Simple reliable HV laser https://str.llnl.gov/str/Marshall.html
 
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joeybab3

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This thread was an interesting read, and congrats! Can't wait to see what you do with it!
 




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