Night Vision Devices

[nbk2000]

I ran across a PDF at a defense contractors association website ( http://www.dtic.mil/ndia/ ) that showed the new Gen 5 NVG.

Don't remember the name of the file since I just copied out the pictures and deleted it since it was boring MIL-speak about fiscal schedules and such.

The item shown (no designation yet) has 4 tubes.

http://server3001.freeyellow.com/nbk2000/NVG_GEN5.jpg

Two to the front for normal stero vision, and one on each side for peripheral vision.

It has a 100 degree field of view with 33 degree in stereo.

http://server3001.freeyellow.com/nbk2000/NVG_GEN5_%20FOV.jpg

And best (worst?) of all? Integrated FLIR using an integrated uncooled thermal detector that shows up in the very center (the square part).

How'd you like to get a pair of these off a JBT? :)

Oh, and flares and bright lights won't really bother the intensifer part because of the improved gain control, and even if it washed out, the FLIR is unaffected.


------------------
"I have begun evil, I shall end evil. That is the end that awaits me."

Go here (http://briefcase.yahoo.com/nbk2ooo) to download the NBK2000 files and videos.

[This message has been edited by nbk2000 (edited 11-28-2001).]

[vulture]

Wouldn't that thing require a huge battery because of the massive energy need?
Aside of that, i would want to have one of those...

You would be able to set off your explosives at night without attracting suspicion by using a flashlight...
And with the flir you could nicely see heat variations in the explosion...

[This message has been edited by vulture (edited 11-29-2001).]

[nbk2000]

Digital Nightvision Headset:

http://www.tekgear.com/index.cfm?pageID=90&prodid=66&section=83&nodelist=1,83

Only $900. :)

[Jacks Complete]

But are they any good? There's precious little info on there, and it's a mono set.

If I ever get over to the US, I'll be buying some of this stuff. It's all legal over here, but you can't get anyone to either ship it or supply it for less than 200% mark-up...

I want two of the Weaver digital scopes to mod into a set of stereo goggles. $199 from binoculars.com, last I looked. £400 ($650) over here!

[sprocket]

There is indeed very little information about these and merely a hint of its specs.

From what I can read the unit doesn't have a thermographic (FLIR) camera and can merely see shortwave IR like all CCDs. You can plug in a thermographic camera, but then you're looking at an additional $5000 in cost and some added weight.

I guess we'll have to wait a little longer until thermographic cameras are light enough to be head-mounted and integrated into night vision goggles.

BTW, why is this thread in chemistry related? :)

[c.Tech]

You would be able to set off your explosives at night without attracting suspicion by using a flashlight...

Doesn't the lenses at the front light up making it look more obvious that your up to mischief, or is this just another one of those things that only exists in the movies?

[nbk2000]

Nightvision devices emit no light from the front that is visible to the naked eye.

The glowing green you see in the movies is just a special effect used so you can see the actors movements. In real life, that'd get you shot.

The digital visor uses IR LEDs and a CCD imaging chip, rather than a amplifier tube like true NVD's use.

Thing I've always wondered about, and never been able to find an answer to, is: What's the shortest duration pulse of light visible to the human eye? A millisecond, microsecond, femtosecond?

There must be a lower limit to it.

By making a device that emitted full spectrum light in pulses too short for the human eye to see, but not too fast for a digital viewer, you could have full-color vision in total darkness, without giving away your position.

And, because of the extremely short duration of the light pulses, range-gating could be applied to provide depth perception/ranging, as it'd be acting like LIDAR. :)

[c.Tech]

By making a device that emitted full spectrum light in pulses too short for the human eye to see, but not too fast for a digital viewer, you could have full-color vision in total darkness, without giving away your position.

Would the short clicks work as a strobe light effect or would they all seem to join together, like the ways old films were made?

If they cause a strobe effect it would cause disorientation and possible seizures/fits, which wouldn’t be very useful at times that you need to be undetected.

Wouldn’t constantly turning on and off at a fast rate cause overheating in the LED's?

[sprocket]

I think the minimum perceivable pulse duration is highly dependant on the intensity (and wavelength) of it. In other words, the energy of the pulse. At least the eye will detect light in this manner. The real question is if the brain can interpret this information or if it's simply overwhelmed and filters it out.

If there was a lower limit it'd probably be on the scale of microseconds to nanoseconds. Photographic flashes are on the millisecond range, and they're quite visible.

[nbk2000]

Wow, I didn't have time to edit my last post before getting two replies. :)

Since the human eye sees 30FPS as a continous stream, and if you used 30 nano-second pulses per second for your imaging, than that means the emitters are dark for 99.999997% of the time. Hardly a dazzling beacon. ;)

A very detailed explaination of the types and uses of range-gating for imagingv(8mb):

www2.foi.se/rapp/foir0856.pdf

Surveillance camera that uses active imaging and range-gating:

http://www.obzerv.com/techno/core-expertise.html#range

The video demos are quite fascinating to watch, too. :)

[nbk2000]

http://camouflage.com/colornightvision.php

By using mechanical filters, with a single monochrome tube, they can produce color images using dim full-spectrum moonlight.

An old idea (to me) that someone with the money finally made real.

[Jacks Complete]

NBK, your first link is now dead, it 404's. Hacking the URL works, though. http://www.obzerv.com/EN/video/jeanPassVSact_large.html shows us that this isn't a great idea, though. Sending a 900nm IR beam at the enemy is going to get you shot very rapidly if they have NVG, range gating or not. It is very smart, though, and the snow demo gives a good indication of the uses for it. (For anyone not familar, range gating is the process of only taking a reading at the point you are expecting a reading. Liken it to the way you look though the chainlink fence at the inmates, but using a fast shutter rather than focus.)

The second one (colour) is interesting, but it isn't really much use, since it only works down to 1/4 moon, and things like the Sony nightshot CCD are already as good or better than that. You can try this at home if you want, take your NVGs and fit a set of rotating wheels to it with matched colour filters. Rotation at 10+RPM should work.

As regards fast laser pulses, it won't work. The eye is an aggregator system, it simply adds up the incoming photons. Add more photons, they get counted. You could go for a system where very few photons extra are thrown out, however. If you look at a short laser pulse, these are often down in the nanosecond range, but they are totally visible. At really low powers (total numbers of photons), it might work, however.

Note that a lot of modern systems using LEDs pulse the LEDs really fast to save power, due to the way the eye works, they can be off for 90+% of the time, yet are still perfectly bright. You can test this by scanning the lights really fast, and you will see them strobe.

[nbk2000]

http://www.rulli.lanl.gov/

A fascinating technology that can image objects into 3D, such as trees, showing their interior layout, as well as defeating camofluage, using nearly zero ambient light (single photons! :eek: ).

[Alexires]

Shit on me batman!

That RULLI is pretty scary stuff. The timing function gives it the ability to gauge distance which is pretty dangerous too, but remember, its just light. There is a maximum range that the RULLI can "see" at, but still, very scary.

Depending on what wavelength they use for the laser, it MIGHT be possible to interfere with it using some kind of non-visible gas for example, if the laser was a IR laser, then CO2 may be used to interfere with it.

Think Nitrogen grenades or CO2 grenades for use in changing the density of the air as well as the way the photons interact with the medium.

Expanding on that, you may be able to make grenades that are either hot or cold, depending on the air temperature around. If it is a hot night and you are in a field and scared of being picked up by RULLI, a compressed N2 grenade will shoot off cold N2 gas which will cause a kind of ripple in the imaging and confuse the sensor.

Think looking above a fire and seeing all the ripples. Same deal if it is cold and you use a hot grenade.

Also, remember they are just pictures. Imagine trying to see an experienced person in ghillie suit hiding in shrubbery. Doesn't matter if you have 360 photos from all around and collate it into a 3D image, the person is still hidden.

[Jacks Complete]

Alexires, I seriously doubt that using a cold gas would do anything at all. It might wobble the range readings a bit, but it wouldn't acheive much, and nor would a little distortion change much - the image through a fire is still fairly recognisable.

What you could do is detect the precisely timed laser pulses. Given a total reflectivity (after scattering) of 50%, half the photons will never go back to the detector, and you can easily pick those up. You could blind the sensor easily, since detectors designed to trap a single event photon with a multiplier are easily overwhelmed by a few billion, which is still a dim light. You would need the source to be bright at the right wavelength, however.

The reason this can see through camo is because it sees the gaps in the netting and the solid object behind. It is almost the same as the way a person can see a thing behind a hedge, like a car, and work out it is a car, from the many small bits of light that get through the myriad gaps. In this case, however, they are moving the camera, rather than the target moving.

However, this is quite neat. I'm sure someone will think of a neat imaging application for this that can't be done with a stereo pair of photomultiplier tubes, 2 webcams and a small PC.

[simply RED]

Do sb know the range night vision models work (in nanometers). It should be IR anyway...

[Alexires]

Your typical shitty outside IR camera is about 850 nm.

This (http://www.gamma-sci.com/PDFs/ANVIS.pdf) pdf puts Gen3 at about 650nm.

These digital cameras have the range of


Silver220S (http://www.electrophysics.com/Browse/Brw_ProductLineCategory.asp?CategoryID=157&Area=IS) - 850nm to 2500nm

Silver420M (http://www.electrophysics.com/Browse/Brw_ProductLineCategory.asp?CategoryID=156&Area=IS) - 3600nm to 5100nm

Jade590L (http://www.electrophysics.com/Browse/Brw_ProductLineCategory.asp?CategoryID=161&Area=IS) - 7700nm to 11000nm

and this (http://www.electrophysics.com/Browse/Brw_ProductLineCategory.asp?CategoryID=91&Area=IS) camera is a multi spectrum camera. I'm assuming that it covers the whole IR spectrum.

Interesting site (http://www.hownightvisionworks.com/)

Another one (http://www.nightvisionweb.com/ir_illuminators.htm) with various IR illuminators possibly to be used in your home defence.

[nbk2000]

650nm is bright visible red, like a laser point.

[Jacks Complete]

NBK is right, shine 650nm light about and it's pretty bright. 635 is where most modern laser pointers are at, and 650 out to 670 are the older gen laser pointers, which are not as bright to the human eye for the power output. I have a 5mW at 670, and it is really dim, a 635 at 1mW appears far brighter.

Either way, 650 is not even IR.

[Mr Science]

2 Things I have found:
http://www.unitednuclear.com/novairext.htm
^After reading this, I discovered it is only the cheaper quality IR led's that produce red light, and higher quality produce no visible light whatsoever. And judging by the graph on the page, it looks safe to say most IR energy comes from 390nm. Or am I reading this wrong.
http://www.glowproducts.com/glowsticks/infraredglowsticks/
^Do these light up an area with IR, or are these only markers? I am curious.
Sorry if this isnt contributing much, but I just thought it would be helpful to bring to people's attention.

[Jacks Complete]

390nm is far violet verging towards UV. http://ledmuseum.candlepower.us/seventh/3902aa.htm

That graph you link to is completely wrong - the text all talks about 940nm (IR) - I guess they just put the wrong picture in there. In fact, if you look at the UV lamp, it uses the same graph!

As for the IR cyalumes, they are just like regular lightsticks. If you look at them, they are quite bright, but they are terrible for actual throw. Most likely markers only, unless you are using NVG up close (due to the high gain)

[captain clay]

This is my first post,so I hope my interjection is helpful.
You can now buy infra-red lenses for sure-fire and streamlight brand flashlights, I wonder about how much theoretical gain these would have mounted on a rifle in conjunction with the night vision goggles.

[Jacks Complete]

Incandescent lights give out about 80% of the input power as IR, from memory. Using an IR filter gives you a lot of light, and you get further gains from the NVG. So you can see for miles. But, as ever, you are a beacon to those with NVG's looking for you.

[plutobound]

This is a comparitive review of 4 IR illuminators

http://www.ar15.com/content/products/lights/irIlluminatorShootOut.html

[nbk2000]

While NVD's are great to have, it may occur that you don't have any, but your opponent does.

How do you see in the dark, without giving yourself away to your better-equiped enemies?

White-light is out of the question, and putting a red filter over the light doesn't impede detection by NVD's, since it'll let through far more in IR than visible red.

Ah...but there is an answer!

Electroluminescent panels. :)

Better known as the glowing green light called 'Indi-Glo', as used in Timex watches.

Well, the green light is for shit for stealth, since that is still visible to NVD's, though much less than incandescent light sources.

What you are looking for is a battery-powered device that uses a blue EL panel, as blue is invisible to NVD's on reflection (still visible directly), giving you enough light to move around and bright enough for detail work at extremely close range.

I got mine as a travel alarm-clock for $6.

Because of the very deep blue light, it's difficult to keep your eyes focused on things, and you can't see anything dark-on-dark (not enough contrast), but for navigating in buildings or where the surface is light enough (sand/snow), it's useable.

And even to the naked eye, to anyone looking from more than 50 yards, the reflected light is invisible, though direct is still quite visible.

[nbk2000]

Found a patent, US6611200, for a "Tint Buster".

This is a surveillance device that uses an infrared light source, like a filtered spotlight, coupled to an IR sensitive videocamera, to see through standard window tinting, on either cars or building windows.

[Cobalt.45]

Has anyone had a chance to try the "EyeClops" night vision toy? Ad says "see up to 50 feet" but I'm guessing the IR source that's supplied might be the limiting factor. Not cheap, either (~ $80 US).

If you used a portable IR source, these might be useful...:cool:

Another interesting toy is an up to 400X magnifier that displays on a TV.
http://jakks.com/construct.php?section=toys&subsection=ces2008&page=ces2008

[iHME]

I found these plans for a homemade nightvision device on some random forum.
Compiled the original jpeg's to a pdf for you people.

It is technically similar to that Jakks toy that Cobalt posted.
It uses a low lux ccd camera module, some ir leds and a viewfinder from a camcorder.

Considering that I have one old sony video8 camcorder with a dead battery and conveniently removable viewfinder I might even try this, some day.


Edit:
Damn, it did not include my attachment.
Oh bloody hell, how did abiword make four jpeg's that have the combined size of 650kb to a 12mb pdf?

Well here, grab some rapidshit of the original jpeg's:
http://rapidshare.com/files/145013138/diy_nv_gear.zip

[Jacks Complete]

You can buy these commercially. Or use a Sony with the Nightshot hooked up so it works daytime.

The Weaver digital NVG scope works like this - it's a low lux camera and a fairly powerful IR thrower, with a good eyepeice and a video out jack. They are <$200 or around £400 (Yes, $800 nearly - the UK gets ripped off for that sort of stuff!)

[Cobalt.45]

They are <$200 or around £400 (Yes, $800 nearly - the UK gets ripped off for that sort of stuff!)If you want one, just say the word and I will be glad to purchase it here in the US (with your funds, obviously;)) and send it across the pond to you, no problem.

That kind of a rip makes me pissed!:mad:

In my fit of pique, I didn't stop to think that this was better PM'ed. My bad.

[waveguider]

Is the ''Weaver digital NVG scope'' this device?

http://cgi.ebay.com/Weaver-NightView-Digital-Night-Vision-Scope-_W0QQitemZ320304136005QQcmdZViewItemQQimsxZ2008092 6?IMSfp=TL080926155009r18789

http://www.optics4birding.com/nightview-digital-nightvision-3850.html

If so then that's a good price!
I also have this in my bookmarks which you guys might like, it's a DIY project similar to what is mentioned above.
http://geektechnique.org/index.php?id=254

If I were to get one myself I would go with the following because of it's 36 lines/mm which is as said one of the best gen 1 one out there.

[Jacks Complete]

Yes, that's the one.

The video output is a nice touch, plug it into a recorder or monitor!

[iHME]

I'd suggest backing up the article from geektechnique.org. The author has died recently from heart attack and I don't know if anyone is paying for the connection that keeps his servers up.

[-=HeX=-]

Cobalt .45: once I get a new laptop I am buying the eyeclops device, I saw it in popular science. 80 dollars is extremely cheap for night vision devices, and I will be adding on my own infra red light source. Once I buy it I will write a review of it.

[waveguider]

I'd suggest backing up the article from geektechnique.org. The author has died recently from heart attack and I don't know if anyone is paying for the connection that keeps his servers up.

Poor guy, and I will do, thanks!
I have to apologise, my above post ended without me entering the link to the scope I would puchase (silly me).
Yukon Advanced Optics 3x42 Night Vision Waterproof Monocular:

http://www.amazon.com/Yukon-Advanced-Optics-Waterproof-Monocular/dp/B0002HBOPQ/ref=pd_sim_dbs_p_1

[MinorFunctionary]

Just a fast and dirty pdf of the geektechnique article, for those that want it.

http://rapidshare.com/files/155733687/__geektec_254.pdf.html