Night Vision Image Intensifier Tubes
The image intensifier tube is the component at the heart of an analog night vision system. It collects available light and converts it into the intensified image viewed through the eyepiece, making tube selection one of the most important decisions when configuring or upgrading an NVG.
Quad Defense offers image intensifier tubes for monocular, binocular, and other compatible night vision systems, with options from manufacturers including L3Harris, Twenty Six Defense, Photonis, NVT, and other available suppliers.
Understanding Night Vision Tube Specifications
No single specification tells the entire story of an image intensifier. When comparing tubes, several specifications should be considered together to understand their overall performance.
- SNR (Signal-to-Noise Ratio) — describes the tube's ability to produce a usable image relative to image noise, particularly as available light decreases.
- Resolution — measured in line pairs per millimeter (lp/mm) and describes the tube's ability to resolve fine detail.
- FOM (Figure of Merit) — calculated by multiplying SNR by resolution. FOM is useful for comparison, but should not be used as the only measure of tube performance.
- EBI (Equivalent Background Illumination) — represents background output generated by the tube itself and can become more relevant in extremely low-light conditions.
- Halo — describes the size of the visible bloom surrounding bright light sources.
- Gain — describes the amount of amplification produced by the image intensifier.
FOM Isn't Everything
FOM is one of the most commonly advertised night vision specifications, but two tubes with similar FOM values can perform differently depending on their SNR, resolution, EBI, halo, gain, cosmetics, and overall characteristics.
For this reason, Quad Defense evaluates the complete specification set when selecting and pairing image intensifier tubes rather than relying on FOM alone.
White Phosphor Image Intensifiers
White phosphor image intensifiers produce the familiar monochromatic white-to-gray image used in many modern night vision systems. They are available across multiple performance levels and technologies depending on manufacturer and tube model.
Quad Defense carries available white phosphor image intensifiers from manufacturers including L3Harris, Twenty Six Defense, Photonis, and NVT, allowing systems to be configured around different performance requirements and budgets.
Matched Tubes for Binocular Night Vision
Binocular night vision systems require two image intensifier tubes operating simultaneously. While the tubes do not need identical specifications, properly pairing them helps create a more consistent image between the user's left and right eyes.
QDEF evaluates tube specifications and image characteristics when pairing intensifiers for complete binocular builds.
Upgrading Existing Night Vision Tubes
Replacing image intensifiers can significantly change the performance of an existing night vision system without requiring a completely new device. A quality housing and optics package can often be retained while the existing intensifier tube or tubes are replaced with a different performance level.
Quad Defense offers night vision service, tube installation, housing upgrades, inspection, purging, and related work through The Service Bench.
Build a Complete Night Vision System
If you're starting with a new system rather than upgrading an existing device, use our Dark Room configurator to select the housing, image intensifier tubes, and optics together.
Build Your NVG in The Dark Room →
Learn More About Image Intensifier Tubes
Understanding specifications is one of the most important parts of buying night vision. QDEF Technical covers image intensifier performance, specifications, housings, optics, and other night vision fundamentals in greater detail.
Read Night Vision 101 →
