2017 top 10 professional UV flashlight

Yeah, just found this on Google, UV used to detect fakes basically: “Polymer-treated jadeite jade (known as ‘B’ jade) is first bleached to remove unwanted brown, yellow, and black stains and then polymer-impregnated to improve transparency. Structural damage occurs with this treatment, making the jadeite brittle. A chalky blue reaction under long-wave UV light is a good indication that jadeite has been polymer-impregnated, but the definitive test is infrared spectroscopy, which shows polymer peaks around 2900 cm –1 (wavenumbers).

Dyed jadeite jade is known as ‘C’ jade. It has additional amounts of chromium when dyed green, so the absorption band at 670 nm will be wide and strong, while natural-coloured jadeite has fine absorption lines of about 690 nm (Figure 7). The colour is unstable and fades under high heat and over time. The dye can be added to the polymer during the impregnation process, and the result is a chemically bleached, dyed, and polymer-impregnated jade (‘B+C’ jade). Dyed cracks may be visible with the use of a microscope (Figure 8, page 4). In addition, dyed jade fluoresces medium to strong greenish yellow, while natural-coloured jade usually does not exhibit any fluorescence.”

Jade special crystal structure basically makes it unbreakable, you cant split or crack jade, and if 2 different parts are glued together you can see it when looking on it closely

Normally only sawing, grinding and sanding can be used to bring jade into shape, splitting it as other mineraly is not possible

UV can be used to detect fake jade

Jaxman U1 365nm and some jade and stones identification etc.
Pictures inside, for those who are interested.

https://item.taobao.com/item.htm?spm=a230r.1.14.64.51af49faNxQhXE&id=40385473100&ns=1&abbucket=12#detail

Holy , is this for home use? And i thought my 2 x 55W is powerful. :smiley:

Hm, the best surprise is yet to come. I filed a patent for mobilising contraptions added to carriages, so you don’t need a horse anymore. Also applicable to carts for donkeys, goats an dogs. $1 per pop ain’t that bad?
The patent covers the transforming of any form of external energy into a forward (and/or backward) motion. For that I have identified and described nano sized worm holes. To say it in layman terms: there is no fluent motion, but the carriage jumps from hole to hole.
Ever freeze framed a movie with a speeding car(t)? QED. A car(t) can jump many feet before it re-appears.

Here a picture of my more than 25years old 125W UV Bulp. The choke coil is still somewhere in my not opend moving boxes in the basement.
I got this light from a electrician while i did a traineeship during my school time. They used it to delete old EPROMs. It puts out a lot of UV light.

Is there a low-pressure mercury CFL type in there? Without the phosphor of coz. Then the typical blackbulb coating for the external glass?

Nowadays it’d be like this for BLBs that are not long tube T12, T8 or T5.

Left or right?

Its like the HSW (left Bulp at the beginning of the clip). Takes a few minutes to get to full brightness.
The bulp still workes and we used it for years when we get back from party for long afterhours :sunglasses:
A few years back i put some new solder on the bottom contact because the original was getting thin.

I’m trying to get my head around this and am looking for feedback.

Looking at Simon’s Convoy store I see:

  • Convoy S2+, w/ Nichia 365UV, w/o ZWB2 filter
  • Convoy S2, w/ LG UV 365nm LED, w/ ZWB2 filter - not shipping to US

You could of course add your own ZWB2 filter later. (I won’t tell anyone.)

Now my questions -

  • Looking at djozz’s 365nm LED comparison chart, it looks like the LG UV 365nm produces more output at 1A than the Nichia (1300 vs 750). Am I reading things correctly.
  • A number of people have commented about the S2+ w/ Nichia being a little over driven, and perhaps damaging the LED after extended use. Is the LG UV 365nm any better with regards to 1amp and heat?

I also see that Simon sells the LG UV 365nm on a 16mm DTP board. I’m pondering buying the LG, plus an S2+ host, driver, and ZWB2 filter.

Would this be any better/worse than the off-the-shelf S2+?

(I am of course thinking why not buy both.)

Mr. Scott - the problem is that the Convoy S2 simply cannot efficiently handle the heat produced by either LED. The LG part is even worse than the overdriven Nichia, higher current, more heat. But from a performance viewpoint, depends on what you are looking for. The smaller Nichia die seems to produce a tighter, more intense spot. The LG part results in a larger, less intense spot even though it is higher power. With the different spot sizes they are about equal in intensity (measured with a UVA meter).
The Convoy S3 host seems to be better at heat handling I think - if you’re into rolling your own with a copper board.
Of course the ZWB2 filter is a must for serious use (i.e. - fluorescent minerals, the only thing serious to me :wink: )
Some offer LG Convoys @ 5watts (but really under 4W); they get hot, quick. But I haven’t had one go bad on me yet - (have probably up to 8 different flavors by now). I did build an LG light at true 5 watts (1050ma drive) - gets real hot, but so far ok (Convoy S3 host).

For performance of the different leds, you can check my test from March this year: 4 more 365nm UV-leds tested

@Mark, as a Nichia alternative, you can also check the Seoul Viosys led sold at Kaidomain, it has a smaller die than the LG led and is way less sensitive to overcurrent than the N.276A.

Funny that in actual use in lighting up minerals, overheating of the flashlight becomes a real problem even though the led can can handle that heat, it is something generally not regarded as a problem here on BLF where extended use usually does not occur. :slight_smile:

Djozz - the CUN66A1B LED starts derating at 35c while the others start quite a bit higher. That’s why I have not tried that LED. Perhaps I will give it a look. I noticed a “triple” using that LED (I think) on the Kaidomain website. It included optics for the three LEDs in a 20mm package. Interesting, but in my research I have found that plastic optics reduce the UVA output by 20% to 40%. Even the silicon domes directly on the LEDs reduce the UVA output. That’s one reason the Convoy with aluminum reflector is better for our hobby.

Very true that we use these lights with a much longer duty cycle. Our goal is to hunt for rocks at night, and requires scanning lots of ground. Which brings up another shortcoming of the Convoy. The 7135 drivers work fine for the first half hour when the battery is fully charged. But as the battery slowly discharges it drops below 3.7v and affects the output of the LED.

But for $20 (now higher due to market strangulation here in the USA) it’s still a no-brainer for us.

Incidentally, here’s a pic of one of my high-power lights used in our displays - 15 watt (4ea LG LEDs, or one LED higher voltage, depending on my mood)

Not sure you you mean (degrees Celsius?), it may be my limited knowledge of english. But in that case yes, my led tests tell nothing about how stable the led is at extended use, and with UV leds this is important knowledge.

KD just sells the triple without much knowledge of the losses that the optic causes, a bit silly.

Yes, 35 degree celsius. Wish there was a way to insert a pic of the graph without having to upload to an ftp site…

I understand how the challenge here is to overdrive and get every drop of light out of an LED. But from a production standpoint, where the LEDs could be on all day long, I simply cannot drive them to that point. I don’t ever exceed absolute max ratings, but I do push to the limit. But am very aware of cooling since this is critical for UV LEDs.

20 watter 365nm Jaxman X1S?

https://item.taobao.com/item.htm?spm=2013.1.20141002.6.5aac2c23g17poA&scm=1007.10009.70205.100200300000001&id=570480508974&pvid=0248de9b-ddad-4130-8b3d-aee1fb0b6590

25 metres

I remember seeing a 50 watter custom DIY one (multi emitter?) but i can’t seem to find it now.

Yes, I have examined your data before - very helpful, and I thank you for that. Side question - UVA meters are available for a reasonable price. Is there a reason you do not use that for output measurements?
One concern I have is saturation of the fluorescent object. Bleaching is another concern which you noticed on the white paper. UV does some really strange things. It can cause an object to change its natural color (tenebrescence), or to fade (bleaching), sometimes by very small amounts - almost undetectable. I photograph a lot of fluorescent minerals and have noticed that there is an upper limit to the amount of “glow” regardless of the amount of UV applied. Not sure about U glass as I have not photographed that.

Is this a standard product or custom modded? I can’t find it on the Jaxman store. Uses the Nichia NVSU333A chip?
Edit - just found it (followed your link - duh!). I found the text on the website very interesting - LOL. Kind of refreshing to see a company advising folks not to buy it! 20 watts of UV LEDs in that host is certainly pushing the envelope. In our use (on for an hour or more) will likely have a limited life.

“This powerful UV lamp is powerful (maximum 20 watts, for safety and comprehensive balance, we set it to work at 18 watts), which is hugely hot and costly.

We don’t want users who just follow the wenwan banknotes to choose this product. We are just special products that are pursued after chasing the latest optoelectronic technology. If it is not necessary, we strongly recommend that you do not buy it”

I did not find saturation of the U-glass: with a UV-led at max I did readings at different distances from the glass, so illuminating a smaller and larger area, and I found the same reading.

Yes, a UVAmeter would be nice. They are available for around 150 euro’s which is not cheap for me but I have bought more expensive equipment too. My UV-led measuring method sort of developed from my former methods so I never looked into special UV-meters, but perhaps I should at some point, at least to validate the way I measure it now. Do you have experience with which UVA meter performs well for the price?