IMAGE INTENSIFIER OPTICS

WWII-era British “Tabby” active-infra-red night-vision viewer – essentially the ancestor of modern image-intensifier goggles.
Right-hand unit (glass section + braided HV lead)
Image-converter tube assembly (EMI type CV147/CV148 family) with its eyepiece lens and a single-core, screened high-voltage lead.
The photo cathode on the front window converts incoming IR light (reflected from an IR spotlight) into electrons; the 3-electrode stack focuses them onto a phosphor screen at the rear, which the eyepiece magnifies for the user. It needs ~3 kV supplied through that ceramic-tipped plug.
Left-hand unit (all-black, bigger front lens)
Matched objective/relay lens module. Screws onto the converter tube so the whole assembly is ~160 mm long – the design length for this first-generation night sight. The side connector is a test socket for the Zamboni-pile (dry-cell) HV stack that lived in the mounting bracket.
How it worked.
1. A vehicle- or weapon-mounted IR spotlight (invisible to the naked eye) illuminated the scene.
2. The objective lens sent that light into the image-converter tube.
3. Inside the evacuated glass cylinder, the photo cathode/electrode/phosphor stack amplified the signal by several hundred times.
4. The green-glowing screen was viewed through the eyepiece, giving the operator a bright monochrome picture out to roughly 150 m.
A bit of history.
Britain codenamed its early IR kit “Tabby” (after the cat that sees in the dark). First issued in 1943, it equipped SOE teams, commandos and tank drivers on D-Day convoys. Roughly 3,000 sets were built before war’s end. They were heavy, power-hungry and needed the external lamp, but they let operators see without giving away visible light – a huge tactical leap at the time.
So, the two tubes in the picture aren’t a microscope or camera part – they’re the heart of a pioneering night-vision scope that let Allied soldiers drive and fight after dark three-quarters of a century ago.

Identified by Joshua Jones, Kansas City, Kansas, U.S.A., 30th of April 2025

Donated by Ken Willis

Your comments:

• WWII-era British “Tabby” active-infra-red night-vision viewer – essentially the ancestor of modern image-intensifier goggles.
  
  Right-hand unit (glass section + braided HV lead)
  Image-converter tube assembly (EMI type CV147/CV148 family) with its eyepiece lens and a single-core, screened high-voltage lead
  
  The photocathode on the front window converts incoming IR light (reflected from an IR spotlight) into electrons; the 3-electrode stack focuses them onto a phosphor screen at the rear, which the eyepiece magnifies for the user. It needs ~3 kV supplied through that ceramic-tipped plug
  
  --
  
  Left-hand unit (all-black, bigger front lens)
  Matched objective/relay lens module
  
  Screws onto the converter tube so the whole assembly is ~160 mm long – the design length for this first-generation night sight. The side connector is a test socket for the Zamboni-pile (dry-cell) HV stack that lived in the mounting bracket.
  
  How it worked
  1. A vehicle- or weapon-mounted IR spotlight (invisible to the naked eye) illuminated the scene.
  2. The objective lens sent that light into the image-converter tube.
  3. Inside the evacuated glass cylinder, the photocathode/electrode/phosphor stack amplified the signal by several hundred times.
  4. The green-glowing screen was viewed through the eyepiece, giving the operator a bright monochrome picture out to roughly 150 m.
  
  A bit of history
  
  Britain codenamed its early IR kit “Tabby” (after the cat that sees in the dark). First issued in 1943, it equipped SOE teams, commandos and tank drivers on D-Day convoys. Roughly 3,000 sets were built before war’s end. They were heavy, power-hungry and needed the external lamp, but they let operators see without giving away visible light – a huge tactical leap at the time.
  
  So, the two tubes in the picture aren’t a microscope or camera part – they’re the heart of a pioneering night-vision scope that let Allied soldiers drive and fight after dark three-quarters of a century ago.
  
  .......... Joshua Jones, Kansas City, Kansas, U.S.A., 30th of April 2025
  
  

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