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ArcticMyst Security by Avery

405nm Pen from Etimeshop (Ebay)

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I think he expected the bottom to screw off for the battery, instead of the entire thing screwing in half (as all of the Newwishes do).
 





jbtm

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Yep...I never seen lasers screw apart at the middle. This is my first. I wish the front metal cap came off to adjust the lens. Comparing to my 5mw red pens, the laser dot is a bit larger on my violet laser. Almost by twice the size. I'm going by a guess but at 2" the dot is about 3.5 - 3.9mm, going off the dots reflection with a caliper. My red laser, The cap comes off and you can easily adjust the lens. I'm guessing the violet laser is glued in, or pressed.

I noticed if you look into the aperature (hands off the laser) the lens inside looks yellow'ish...None of my lasers do this :p
 
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It could look yellow because it uses an AR lens for 405nm, but I highly doubt that would be included in such a cheap laser. As for the beam, I must have gotten a good one... I have seriously never seen divergence this good. Are you observing the dot size from a distance? As you probably know by now, this wavelength is really hard to focus on, even for cameras. PS... You can change your signature now.

EDIT: Well, I just went to do a divergence test. But is was difficult, because the beam is actually SMALLER at ~15 feet than it is at the aperture! Yes, I am sure of this. I guess these lasers are pre-focused around 15 feet. I'll do a bigger test after it gets dark.
 
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jbtm

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No, from 2" away it was estimated 4" diameter using glasses that diffuse it to look whitish. So no glare. At about....20ft (by a guess!) the diameter is 3.46mm I redid a measurement for 2" and it's actually ALMOST the exact same. My point was just the fact that my 200mw green and 5mw red laser has a smaller diameter dot...As my bluray i felt was wider. Must just be the lens they used. As you stated, these have VERY good divergence, as I almost want to say it was the exact same from 2" to 20ft.
 
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Usually fat beam = good divergence. Mine's probably about 3.5mm also. Do you have a GITD board yet?
 

jbtm

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I'm sorry but I dont know what a GITD board even is ;) So id have to say no...No way to measure the beam mw output either
 
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Glow in the dark?

IMG_4500.jpg


They are so much fun.
grin.gif
I picked up a can of glow in the dark spray paint for $7, and just sprayed a wooden board with it. It's a necessary piece of equipment for any blu-ray owner!
 

jbtm

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Oh...I must get one. I only have a 3" wide star! I'll remember to get some...Maybe use that foam poster board for cheap 3x4ft glow board :) Willl do!!!! Glow spray is that good i take it? To hobbyworld!!! If only they had a material that glowed for 5 mins or more...Etch-A-Sketch laser style...
 
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If your eyes are totally adjusted to the darkness, this stuff will still be glowing faintly about 3-4 minutes later. I use the paint made by Valspar.
 
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This laser has a boost driver (obviously) that is very respectable looking. I hope to have some pics and specs of it soon. They might be a good source of drivers for diodes needing a lower current.

I'll post pics tomorrow :D
 
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...because the beam is actually SMALLER at ~15 feet than it is at the aperture! Yes, I am sure of this. I guess these lasers are pre-focused around 15 feet...

Thanks for the tip. I did all my divergence tests from 5 ft away... i'll try this from 15ft to see if I get a tighter beam at that distance. I have two BR pen from two different chinese resellers. I'll have to see if there's a difference between the two.
- Robert
 
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This laser has a boost driver (obviously) that is very respectable looking. I hope to have some pics and specs of it soon. They might be a good source of drivers for diodes needing a lower current.

I'll post pics tomorrow :D

Wait, wouldn't you not want a boost driver for lower current diodes? I'm confused, it seems to me that they would need less current, not a boost... But then again I'm not a DIY guy.
tongue.gif
 
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Wait, wouldn't you not want a boost driver for lower current diodes? I'm confused, it seems to me that they would need less current, not a boost... But then again I'm not a DIY guy.
tongue.gif
Boosting voltage, not current, is what we are talking in boost drivers, which are also commonly called DC/DC converters,
Basically, all bluray type diodes work on around 5 V, but you might have noticed we use 2x AAA to power these.
There is a driver which performs the conversion of two values, Current and Voltage, for suitable applications.

For instance, my boost driver in my GGW build, uses 350mA from 3.7 V battery, to get 190mA at 5 V on the output (to the diode).
 

jbtm

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I did do a 2 sec exposure to increase the brightness...But I got it from hobby lobby. Lemme tell you that personally I felt this was the worst spray paint I ever bought. I held it for over 5 mins to do small areas because it came out so horrible, I was getting more air than paint and I even got sick of it, shook it a lot for 3 mins, and it still sucked. Next time I'll try my local hardware store, Gemmens...

Hobby lobby sells it in a ~6 x 2 inch mini'ish can. I spray painted foam board, with a paper matt...So it did bend a bit.
 




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