hunter-larry@CS.Yale.EDU (Larry Hunter) (09/24/88)
Ok, let's talk about night vision for a bit. What is the
"$$$GEN III" image intensifier? Where is the technology these
days? I remember seeing some really small handheld gear for
people with nightvision problems, etc.
I think he means third generation light amplifier. The basic alternatives
in night vision gear are light amplifiers (aka image intensifiers,
starscopes) and infrared viewers (and light sources). Light amplifiers
are nice in that they are passive (no one can find you by your light
source) and can provide better images, but IR is much cheaper and pretty
effective for most applications. They're not as expensive as you might
think if you're smart about shopping around. First, if you're looking
for second hand stuff, avoid first generation (multi-tube or multi-stage)
light amplifiers -- they just don't work that well. Second generation
stuff is pretty impressive. I don't know what third generation means
exactly; they haven't made it into the markets I'm familiar with. Here
are some real products that might be of interest:
Light amplifiers:
SEC (Standard Equipment Company) / 9240 N. 107th St. PO Box 2360 / Milwaukee WI
53224 : NVS-80 75-1200mm monocular night scope (for mounting on a camera) $2795
Edmund Scientific (Great source, low prices!) 101 E. Gloucester Pike /Barrington
NJ 08007 : Night Vision System K31073 75mm including eyepiece $2495
InfraRed stuff:
ETCO Electronics / North County shopping center/ Rt 9 north/ Plattsburgh, NY
12901 : Excellent infrared viewer and source powered by 4 D batteries. Light
weight, possible to take excellent photos, field of view about 150 ft. Price
is $279, + $10 for a battery pack and $15 for a 10X objective. There may be
an even cheaper kit version available now. Great deal!
Edmund also has a variety of IR sources, conversion lenses and viewers. You
could add a high power IR source to the ETCO viewer and have a gadget that
the "surveillance retailers" sell for $4000+ for less than $500.
Happy viewing....
Larrycarl@aoa.UUCP (Carl Witthoft) (09/30/88)
[posters asked about image intensifiers, GenI,GenIII definition]
Take it from someone who regularly buys these things for industrial
use:
"light amplifiers" is a nontechnical term. It could just as easily
be applied to a laser amplifier stage as an image intensifier.
All image intensifier tubes (IIT) convert photons to electrons with
a photocathode (like a photomultiplier tube does), then amplifies
the electron (current) and excites a phosphor screen to generate
secondary photons (like a TV tube).
GenI : old device, still in use. Electrons are accelerated thru
focus electrodes, 5 to 30 kV, the high energy of the electron allows
a spray of photons to be emitted when the electron hits the phosphor.
GenII: uses a microchannel plate to provide for massive multiplication
of electrons. May or may not have electron focussing electrodes in
front of or behind the MCP. Same cathode & phosphor setup as GenI.
GenIII: like GenII but with GaAs (or other) cathode for extended
red- infrared response.
Get lots more info from ITT-Indiana or Varo Corp - Plano,TX.
--
Alix' Dad ( Carl Witthoft @ Adaptive Optics Associates)
" Axis-navigo, ergo sum."
{ll-xn,spdcc,...}!bbn!aoa!carl
54 CambridgePark Drive, Cambridge,MA 02140 617-864-0201
"disclaimer? I'm not a doctor, but I do have a Master's Degree in Science!"