6 ms·
This is good, the usage for UV is huge and anything that reduces costs will only help. Whilst many don't need it, I'm sure having a UV filter of your water wou
by Zenst 7y ago
This is good, the usage for UV is huge and anything that reduces costs will only help.
Whilst many don't need it, I'm sure having a UV filter of your water would not go amiss.
- m-p-3 7y agoOr maybe for photolithography hobbyist.
- pressurefree 7y agoor super lo-po phosphorescent LEDs
- jjoonathan 7y agoYeah, especially because that hinges on having coherent light, whereas sterilization does not AFAIK. As for incoherent UV light, I wonder how this laser compares in efficiency to arc lamps. Is that still how incoherent UV is generated? Deuterium and mercury vapor? Or have LEDs taken over?
- Zenst 7y agoA solution that does not use mercury, then that will make for cheaper and equally safer production and dispose.
- fsh 7y agoDUV for lithography is usually produced with excimer lasers at 248 or 193 nm. While they are technically lasers, they are barely coherent and have horrible beam quality. For other applications such as sterilization or curing adhesives, mercury vapor lamps and LEDs are popular.
- anonymfus 7y agoIs photolithography at home limited by laser'd wavelength?
- deleted 7y ago[deleted]
- fsh 7y agoDUV LEDs have existed for quite a while and produce a lot more power.
- lightedman 7y agoUVB/UVC LEDs barely touch 2% efficiency converting energy into photons. When they can hit 30%, I'll have the perfect mineral hunting lamp designed and built.
- mrpeanutbutter 7y agoHandheld UV water purifiers are already common. A lot of backpackers use them. I'm not sure how they work. Presumably they're not using LEDs.
- analog31 7y agoThey use mercury lamps. I took one apart to use the lamp as a wavelength standard. Don't try that at home, the sterilizers have interlocks to prevent accidental eye and skin exposure.
- DoctorOetker 7y agoI have been considering doing this too. Do you have any specific advice, you would have loved to give your prior self?
- analog31 7y agoYes. Don't do it. Buy the nice little mercury-argon lamp from Ocean Optics. First of all, the mercury lamp is dangerous, for real. Second, the newer sterilizer pens contain complicated interlock circuitry, making it impossible to figure out how to actually get the lamp to turn on by itself. I got one lamp to light up from an external power supply, then set it aside and bought a few of the Ocean Optics boxes. As a wavelength standard, it was also a poor configuration -- most of the light can't be directed where you need it, whereas the Ocean Optics produces a nice compact beam and has a fiber optic connector.
- DoctorOetker 7y agothank you very much for the swift reply, I actually don't need it as a wavelength standard, but as a small source for entangled photons. I'm well aware of the dangers of deep UV and ozone (and of mercury if I would accidentally break the lamp by opening the sterilizer pen). I'm unable to identify what Ocean Optics box you are referring to? If I do have resort to the sterilizer pens, any advice regarding opening up and analyzing the interlock circuitry? I have an oscilloscope...
- ruslan 7y agoEven more, they are getting pretty close to x-ray now which begins at 10nm. The laser structure was grown on the (0001) face of a single-crystal aluminum nitride substrate. The measured lasing wavelength was 271.8 nm with a pulsed duration of 50 ns and a repetition frequency of 2 kHz.
- thechao 7y agoI know this is a pipe-dream, but a 2.5Å x-ray laser would be a scientific revolution for protein crystallography. Instead of ~2-10(!) years to find the structure of a protein, we’d be limited by the chemistry.
- robocat 7y ago> I'm sure having a UV filter of your water would not go amiss You don't need lased light for that (and using a low efficiency, high cost device also not ideal?!).
- amluto 7y agoUV LEDs seem to be in development. The problem with UV fluorescent tubes is that they have horrible cycle life.
- pg_is_a_butt 7y agoMore like in production for years. What do you think powers those "instant curing glue" lights that have been helping old ladies glue together their purse straps for over a decade.
- dbtx 7y agoI guess everyone means UVC here. A UVA flashlight is cheaper than lunch ;) edit: my facts were scrambled. C is the nasty one... maybe my favorite (unsafe) language will help me remember that from now on.
- hanniabu 7y agoWould be very useful for vitiligo treatment.
- cies 7y ago> I'm sure having a UV filter of your water would not go amiss. UV "filter"? I thought the UV thing in water treatment was merely to kill most (if not all) of what micro-life would otherwise still live in yr water. Filters are needed to actually get some (dissolved) solids --possibly UV-zapped micro org corpses-- out of yr water. Most places add chlorine/chloramine to the tap water to prevent micro orgs becoming so prevalent "at the faucet" that you can get "cannot go to work tomorrow" sick.
- zdragnar 7y agoYes, if you live in an area with municipal water treatment, but if you rely on a private well, accessible and inexpensive UV treatment would be great. Of course, you also (generally) need a water softener and perhaps more expensive filtering equipment depending on the what metals and minerals might be present.
- cies 7y agoWhy would one need a UV if there's also going to me actual filters after that? (honest question) Only thing I can think of is to prevent contamination of the filters.
- tsomctl 7y agoBecause if you have an actual filter that is a small enough micron to capture pathogens, it's also going to capture all of the really fine sediment and plug up quickly.
- cies 7y agoThat why most water filter systems have "stages", every stage "covers" for the next.
- zdragnar 7y agoIt is entirely site specific. I don't have any filters, just a water conditioner (since I don't want to deal with a softener). Adding UV would probably be unnecessary but would provide some nice peace of mind.
- fyfy18 7y agoBit of a tangent, but do the blue LEDs that hand driers often have now do anything? Or is it just marketing buzz?