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IR goggles
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RichD
Feb 9, 2012, 8:44:45 PM2/9/12
to
How do IR, night vision gogglles work? I'll guess, much like digital
cameras - lenses, sensor, viewscreen, amplifiers and necessary
electronics. My question is, could a unit be designed to operate
completely passively, just lenses and filters, i.e. no battery
required,
like hand held binoculars?
I had assumed these devices were regulated, limited to Big
Brother's storm troopers, can't let the peons have access to
dangerous toys! But then I saw an ad for one at a sporting
goods shop (aimed at hunters) (deer, not man hunters,
presumably). This is a case where I'm glad to be wrong.
--
Rich
cameras - lenses, sensor, viewscreen, amplifiers and necessary
electronics. My question is, could a unit be designed to operate
completely passively, just lenses and filters, i.e. no battery
required,
like hand held binoculars?
I had assumed these devices were regulated, limited to Big
Brother's storm troopers, can't let the peons have access to
dangerous toys! But then I saw an ad for one at a sporting
goods shop (aimed at hunters) (deer, not man hunters,
presumably). This is a case where I'm glad to be wrong.
--
Rich
miso
Feb 9, 2012, 9:07:30 PM2/9/12
to
amplification. It will also work with IR illumination, but spewing out
IR gives away your location. NV is not passive, but it is actually more
efficient power wise to use NV goggles than a flashlight. Cost wise,
well.....
Note that CCDs also respond to IR, or more correctly near IR, say 800n
to 1.2um] That is why some so called night vision gear is just a CCD
with IR illuminator.
There is plenty of Russian NV out there. It is hardly regulated. The
better US stuff is regulated, but gear just as good, say EMCCD, is sold
without regulation.
gregz
Feb 9, 2012, 9:46:03 PM2/9/12
to
It uses a vacuum tube and a high voltage source. The tube is all in one.
Light enters the front, and the light is amplified inside by electron
collision, and hits the back screen illuminating it in a green color.
I also have an older Sony camcorder. It has a night vision mode, and super
night vision which appears to slow the scan speed down to get further
enhancement.
Greg
Benj
Feb 9, 2012, 11:20:15 PM2/9/12
to
freshman textbook" who has to answer everyone's practical questions? I
take it you and Freddi are not experimentalists.
You are talking about two different devices here. An IR viewer sees in
the "dark" only because to you (or deer) IR is invisible. So the area
appears dark, but through the "viewer" the scene is actually brightly
lit (usually with an IR LED these days). Many standard camera devices
have response into the IR. Silicon chips often do as do many vidicon
tubes. unless steps were taken to block IR. Here we are talking NEAR
IR which is just out of visible range. Longer wavelengths (like
military FLIR) are usually scanners. Many video cams today have built-
in IR LEDS for "night vision".
A "real" IR viewer (like say used by a "real" physicist in a "real"
lab) is built a bit differently. It is similar in many ways to an
electron microscope. Except the front of the tube has a photoelectric
coating on a window where IR shakes loose electrons. The electrons are
then focused on a fluorescent screen with electron optics. Hence one
can "see" the IR light.
True "night vision" is different. It is similar to the IR viewer, only
the principles of a photomultiplier tube are incorporated so that when
even a single electron (one photon) is kicked out it gets amplified
enough you can see the spot. Obviously these cannot see in NO light,
but can see in VERY low light. They are regulated only by PRICE! :-)
For military use you can see the disadvantage of IR LEDS on your
viewer. Makes you light up into a dandy target!
Whew! OK, finally can you see IR with only optics? Yes you can! You
have to use something known as a "doubling crystal" GREAT physics
there. Go look it up! Hence one can input an IR laser and it doubles
the frequency to green light that comes out the other end. I do not
recommend doing this for a viewer, however, as light intensity must be
VERY high.
I now return you to the folks "smarter than Einstein"....
Say, wait a minute! Why am I explaining all this when I can just rip a
page out of Wormley's playbook?
http://en.wikipedia.org/wiki/Night_vision
Sam Wormley
Feb 10, 2012, 12:02:52 AM2/10/12
to
On 2/9/12 7:44 PM, RichD wrote:
> How do IR, night vision gogglles work?
See: http://www.google.com/search?q=how+does+nigh+vision+work
> How do IR, night vision gogglles work?
Jos Bergervoet
Feb 10, 2012, 3:55:25 AM2/10/12
to
...
well.. important things! (You wouldn't understand.)
--
Jos
>> dangerous toys! But then I saw an ad for one at a sporting
>> goods shop (aimed at hunters) (deer, not man hunters,
>> presumably). This is a case where I'm glad to be wrong.
>
>> goods shop (aimed at hunters) (deer, not man hunters,
>> presumably). This is a case where I'm glad to be wrong.
>
> Why is it always the official "crackpot" who needs to "go read a
> freshman textbook" who has to answer everyone's practical questions?
Others are extremely busy with important things like,
> freshman textbook" who has to answer everyone's practical questions?
well.. important things! (You wouldn't understand.)
--
Jos
Oppie
Feb 10, 2012, 8:36:33 AM2/10/12
to
"gregz" <ze...@comcast.net> wrote in message
news:195147656350533891.72...@news.eternal-september.org...
analogous to a photomultiplier - actually LOTS of photomultipliers in
parallel. Lens focuses light on the front photocathode of the MCP,
generating electrons which are amplified in the channels and then hit a
phosphor screen (instead of the traditional Anode of the photomultiplier).
http://www.morovision.com/hownightvisionworks.htm
news:195147656350533891.72...@news.eternal-september.org...
> I have a Russian nv.
> It uses a vacuum tube and a high voltage source. The tube is all in one.
> Light enters the front, and the light is amplified inside by electron
> collision, and hits the back screen illuminating it in a green color.
>
> I also have an older Sony camcorder. It has a night vision mode, and super
> night vision which appears to slow the scan speed down to get further
> enhancement.
>
I believe that the night vision goggles employ a microchannel plate. This is
> It uses a vacuum tube and a high voltage source. The tube is all in one.
> Light enters the front, and the light is amplified inside by electron
> collision, and hits the back screen illuminating it in a green color.
>
> I also have an older Sony camcorder. It has a night vision mode, and super
> night vision which appears to slow the scan speed down to get further
> enhancement.
>
analogous to a photomultiplier - actually LOTS of photomultipliers in
parallel. Lens focuses light on the front photocathode of the MCP,
generating electrons which are amplified in the channels and then hit a
phosphor screen (instead of the traditional Anode of the photomultiplier).
http://www.morovision.com/hownightvisionworks.htm
alie...@gmail.com
Feb 10, 2012, 9:29:47 AM2/10/12
to
On Feb 9, 5:44 pm, RichD <r_delaney2...@yahoo.com> wrote:
> How do IR, night vision gogglles work? I'll guess, much like digital
> cameras - lenses, sensor, viewscreen, amplifiers and necessary
> electronics. My question is, could a unit be designed to operate
> completely passively, just lenses and filters, i.e. no battery
> required,
> like hand held binoculars?
http://amasci.com/amateur/irgoggl.html
> How do IR, night vision gogglles work? I'll guess, much like digital
> cameras - lenses, sensor, viewscreen, amplifiers and necessary
> electronics. My question is, could a unit be designed to operate
> completely passively, just lenses and filters, i.e. no battery
> required,
> like hand held binoculars?
Mark L. Fergerson
Androcles
Feb 10, 2012, 9:44:22 AM2/10/12
to
"RichD" <r_dela...@yahoo.com> wrote in message
news:c52752ae-11af-4338...@vh10g2000pbc.googlegroups.com...
and a clockwork train set and a pony and a phone I can play
"Angry Birds" on, and NO batteries on any of them.
be...@iwaynet.net
Feb 10, 2012, 5:41:15 PM2/10/12
to
> My question is, could a unit be designed to operate
> | completely passively, just lenses and filters, i.e. no battery
> | required,
> | like hand held binoculars?
> | completely passively, just lenses and filters, i.e. no battery
> | required,
> | like hand held binoculars?
> And I want a ray gun and a Beano Annual and a cowboy outfit
> and a clockwork train set and a pony and a phone I can play
> "Angry Birds" on, and NO batteries on any of them.
Sorry Andro. You destroyed all the last toys we gave you so you aren't
> and a clockwork train set and a pony and a phone I can play
> "Angry Birds" on, and NO batteries on any of them.
going to get any more!
Sam Wormley
Feb 12, 2012, 7:51:25 PM2/12/12
to
Land and See: Infrared and 3-D Vision Systems Combine to Help Pilots
Avoid Crash Landings [Video]
> http://www.scientificamerican.com/article.cfm?id=3d-pilot-vision-air-safety
> Synthetic vision
> The new technology, which this writer observed firsthand during a recent test flight (see video below), actually combines and leapfrogs two earlier technologies only recently being installed on smaller commercial craft. Synthetic vision systems (SVSs) use terrain data culled from actual flights and stored in a database to create a 3-D graphical interface (think Windows or Mac OS) on a screen in front of the pilot and co-pilot, enabling them to see a digital model of their surroundings even when their vision is obscured by darkness or clouds. SVSs also include information about the location of airports and runways, to help guide pilots until they can establish visual contact with their landing destination.
> http://www.scientificamerican.com/article.cfm?id=3d-pilot-vision-air-safety
Avoid Crash Landings [Video]
> http://www.scientificamerican.com/article.cfm?id=3d-pilot-vision-air-safety
> Synthetic vision
> The new technology, which this writer observed firsthand during a recent test flight (see video below), actually combines and leapfrogs two earlier technologies only recently being installed on smaller commercial craft. Synthetic vision systems (SVSs) use terrain data culled from actual flights and stored in a database to create a 3-D graphical interface (think Windows or Mac OS) on a screen in front of the pilot and co-pilot, enabling them to see a digital model of their surroundings even when their vision is obscured by darkness or clouds. SVSs also include information about the location of airports and runways, to help guide pilots until they can establish visual contact with their landing destination.
> http://www.scientificamerican.com/article.cfm?id=3d-pilot-vision-air-safety
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