84b7a5d0   
   XPost: sci.electronics.design   
   From: miso@sushi.com   
      
   On 2/9/2012 5:44 PM, RichD 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?   
   >   
   > 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   
   Night vision and IR are different. Night vision uses light   
   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.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)