Question about night vision technology

[Ben321]

My question is about light intensifier tube based NV monoculars. I know that Gen0 is just an image converter tube, converting near-IR light into visible light. And I know that Gen2 (and higher) produces significant light amplification, of hundreds or even thousands of times. However, Gen1 is a bit of a mystery to me. I've often read that it has some light intensification properties, but I also know that Gen1 uses an external IR illuminator, and this suggests that it may have no light amplification (just like Gen0).

Can anybody here tell me if Gen1 night vision monoculars actually amplify light? And if so, by how much? And if not, then how does Gen1 differ from Gen0?

[tautech]

You might get faster answers if you move this to the Thermal Imagery sub forum.
https://www.eevblog.com/forum/thermal-imaging/

Use the Move button at the bottom left of the page that only you, the OP can see.

[Ben321]

You might get faster answers if you move this to the Thermal Imagery sub forum.
https://www.eevblog.com/forum/thermal-imaging/

Use the Move button at the bottom left of the page that only you, the OP can see.

Thermal imaging is not the same as light intensifier night vision. Light intensifier night vision works with visible and near-IR wavelengths. Thermal imager works with longwave-IR wavelengths. It would be out of place in that section.

[PointyOintment]

https://en.wikipedia.org/wiki/Night_vision_device#Generation_1_(GEN_I)

Generation 1 (GEN I)

First generation passive devices, introduced during the Vietnam War and patented by the US Army, were an adaptation of earlier active GEN 0 technology, and rely on ambient light instead of an infrared light source. Using an S-20 photocathode, their image intensifiers produce a light amplification of around 1,000×,[10] but are quite bulky and require moonlight to function properly.

Citation [10] links to https://www.globalsecurity.org/military/systems/ground/nvg.htm, which says

Generation I
Amplification: 1,000x

The early 1960's was witness to the beginning of passive night vision. Technological improvements included vacuum tight fused fiber optics for good center resolution and improved gain, multi-alkali photocathodes and fiber optic input & output windows. GEN I devices lacked the sensitivity and light amplification necessary to see below full moonlight, and were often staged or cascaded to improve gain. As a result, GEN I systems were large and cumbersome, less reliable, and relatively poor low light imagers. They were also characterized by streaking and distortion.

That page doesn't mention Generation 0, though Wikipedia does.