Ultraviolet Lasers?

[tehfrr]

As of 2020, is there anything useful I'm missing here with respect to small UV lasers?

So far the only thing Ive seen on a small UV laser is that they are uncommon and the only diode is super expensive ($4,758 USD for a 375nm 70mW at Thorlabs). I also saw a YouTube video of a guy who scavenged one from a broken part on eBay and made a laser pointer with it.

I'd like something light and portable that can put UV on an object 500' (150m) to 3,300' (1,000m). Considering looking on eBay for broken parts like the guy on YouTube did, or working the cost of the diode into my budget at some point. But then I'd also have to deal with finding someone trustworthy to assemble it - I would not risk an 4.7k mistake because my soldering skills are so-so.

So whats up, most of the info I read was 5+ years old, is there anything I'm missing that would be worth a look?

 

[Jim H]

I had recently wondered about using a nonlinear crystal as a frequency doubler with a 532, which would give 266, or with a 445 or 405, giving 222.5 or 202.5. I don't know much about them though, to know if it would work or not. But if it would, that might be much cheaper

 

[WizardG]

Well, it's nice to hear that diode @ Thorlabs has come down a bit. But yeah, there's no common consumer product that uses a UV laser so there's no demand for that diode outside of a very small niche. Diodes they make 10,000,000 of.......dirt cheap. Diodes they make hundreds of.....very expensive. Supply and demand.

If you want an ultraviolet pointer at a reasonable price then invent something everyone in the world will want to buy that requires an ultraviolet laser. With a huge consumer base the diodes themselves will drop to 10s (or at most a hundred or so) of dollars and we will all thank you for your gift of affordable UV pointers for the world!

 

[Mattronium]

Even for 405nm, the only recent development is the Sharp GH04W10A2GC.
Otherwise you have to get UV from excimer, tripled/quadrupled YAG, HeCd, etc.

 

[Encap]

Well, it's nice to hear that diode @ Thorlabs has come down a bit. But yeah, there's no common consumer product that uses a UV laser so there's no demand for that diode outside of a very small niche. Diodes they make 10,000,000 of.......dirt cheap. Diodes they make hundreds of.....very expensive. Supply and demand.

If you want an ultraviolet pointer at a reasonable price then invent something everyone in the world will want to buy that requires an ultraviolet laser. With a huge consumer base the diodes themselves will drop to 10s (or at most a hundred or so) of dollars and we will all thank you for your gift of affordable UV pointers for the world!

Exactly --no technical capability or production capability that is not in use already to make them + no large scale demonstrated need $s or demand $s, is just that.
Maybe someone will get/find funding to look into lower cost UV diodes for virus mitigation in light of Covid19 would not bet on it though.

CNI makes a large range from 213nm to 400nm for the market that needs and can pay for them, however all are lab type.

http://www.cnilaser.com/Ultraviolet_laser.htm

There was an announcement of a new/first deep ultraviolet laser diode on 29 Jan 2020 see: https://phys.org/news/2020-01-laser-diode-emits-deep-uv.html " "Our laser diode emits the world's shortest lasing wavelength, at 271.8 nanometers (nm), under pulsed [electric] current injection at room temperature," says Professor Chiaki Sasaoka of Nagoya University's Center for Integrated Research of Future Electronics " Also see https://www.eurekalert.org/pub_releases/2020-01/nu-lde011720.php

 

[Alaskan]

You can buy nitrogen gas UV lasers on ebay fairly cheap, how much power do you need?

 

[RedCowboy]

Here's 70mw of 375nm for 5 grand > https://www.thorlabs.com/newgrouppa...Zq28gVtkeeHL0K9Ny1V9BVjaJcxvPqEhoCg_QQAvD_BwE


Now this is interesting and could prove a harvestable source especially 2nd hand >
https://www.keyence.com/products/ma...z-vwaLE7QzN1MWFMobWEL1osY6a7jjtBoCrpAQAvD_BwE


Also interesting > https://spectrum.ieee.org/tech-talk...ics/diode-lasers-jump-to-the-deep-ultraviolet

 

[Alaskan]

Good finds.

Re the possible harvest source web site:



Seems bass-awkward when the wavlengths are displayed this way, to me, the shorter higher energy UV photon wavelengths should be on the far right side, the lower frequency, lower energy per photon longer CO2 wavelength on the far left. I'm from the RF world, we show frequencies on graphs, not wavelengths (for the most part, always exceptions, re: hams).

 

[Encap]

Seems bass-awkward when the wavlengths are displayed this way, to me, the shorter higher energy UV photon wavelengths should be on the far right side, the lower frequency, lower energy per photon longer CO2 wavelength on the far left. I'm from the RF world, we show frequencies on graphs, not wavelengths (for the most part, always exceptions, re: hams).

That always intuatively doesn't "feel" correct, I agree, nevertheless:
Wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a vacuum at the same speed, the number of wave crests passing by a given point in one second depends on the wavelength. That number, also known as the frequency, will be larger for a short-wavelength wave than for a long-wavelength wave.

The energy of a wave is directly proportional to its frequency, but inversely proportional to its wavelength. In other words, the greater the energy, the larger the frequency and the shorter (smaller) the wavelength. Given the relationship between wavelength and frequency described above, it follows that short wavelengths are more energetic than long wavelengths

• Frequency defines the total number of occurrence of oscillations in a unit time. While wavelength is defined as the length of a wave.
• Frequency measures the time whereas wavelength measures the distance.
• Hertz is the measuring unit of frequency. While meter is the measuring unit of wavelength.
• In relation to speed, frequency is the ratio of speed and wavelength. As against wavelength is the ratio of speed and frequency

 

[Alaskan]

What you said, but as far as scales go, the lower frequency longer wavelengths should be on the left, the shorter wavelength higher freq. on the right, just don't seem right any other way, to express in poor English. Why, because my orientation early on is in relation to frequency, not wavelengt.

(Edit: Just so you understand, I'm not at all lost to your understanding on all of that, I work with RF in my career field as an engineer, RF uses wavelength and frequency too, it's just light at a much lower frequency than UV... ).

 

[Encap]

What you said, but as far as scales go, the lower frequency longer wavelengths should be on the left, the shorter wavelength higher freq. on the right, just don't seem right any other way, to express in poor English. Why, because my orientation early on is in relation to frequency, not wavelengt.

(Edit: Just so you understand, I'm not at all lost to your understanding on all of that, I work with RF in my career field as an engineer, RF uses wavelength and frequency too, it's just light at a much lower frequency than UV... ).

(Edit: I know you are not lost--was just providing some info for people not familiar)

I agree--doesn't seem/feel right but is a "numbers" thing, done like reading--left to right, lower to higher wavelength numbers the reverse for freq and energy-- done to show wavelength and frequency directly across from each other-- 2 charts side by side at same time to easily relate one to the other on a line directly across both, so charts decreasing wavelength to the left and increasing energy and frequency to the left.
Energy is done same as freq. higher on left to lower on right--

 

[WizardG]

You can buy nitrogen gas UV lasers on ebay fairly cheap, how much power do you need?

Now there's an idea: a handheld nitrogen laser. Perhaps powered by one of those 'tesla coil' lighters.

 

[Alaskan]

If I were Qatari, the sides of the scale they used would fit me must fine, they start writing on the right side of a page and go left, I have to use a VPN when filling in web forms, or they automatically force me to enter information that way.

I was wondering if it would be possible to make a UV gas laser portable too, something to run off batteries, hmmm... That's one I won't go chasing after though, too many other things I need to finish first.

 

[WizardG]

I was wondering if it would be possible to make a UV gas laser portable too, something to run off batteries, hmmm... That's one I won't go chasing after though, too many other things I need to finish first.

A portable HeCd? Ooof, thassa lotta batteries

 

[hakzaw1]

TY encap your post answered a few questions.. mucho grabass! amigo..

 

[Buffo]

Equally impractical for your application, but Argon Ion lasers can also output UV (351 nm and 364 nm), albeit at ridiculously low gain levels.

Adam