If you’ve ever watched an old war movie or seen footage from decades past, you might have a distinct memory: soldiers using night vision goggles that cast the world in a strange, glowing red hue. This leads many to ask, did night vision goggles used to be red? The answer is a fascinating look at the evolution of a critical technology.
Early night vision devices did indeed produce a red image, but this was due to the specific type of technology they used. Understanding why they were red, and why they changed, helps explain how night vision works. Let’s look at the history and science behind these iconic devices.
Did Night Vision Goggles Used To Be Red
The signature red glow of old night vision goggles is a hallmark of what’s called “Generation 0” (Gen 0) technology. Developed and used around the time of World War II and the Korean War, these devices relied on a method called active infrared illumination. They didn’t just amplify light; they actually projected it.
Here’s how the old red systems worked:
- An infrared light projector, essentially a big flashlight emitting light invisible to the human eye, was mounted on the goggle or device.
- This light would shine on the scene ahead, like a spotlight.
- The goggles’ lens would then capture the reflected infrared light.
- This light hit a photocathode tube, which converted the infrared photons into electrons.
- Those electrons were then accelerated and smashed onto a phosphor screen—the same type of screen found in old television sets.
- The phosphor screen used in these early tubes was the type that glowed red when excited by electrons, creating the final image the soldier saw.
So, the red image wasn’t a stylistic choice; it was a direct result of the phosphor chemical chosen for the screen. The entire system was bulky, required a large power source for the IR illuminator, and had a major tactical flaw: anyone else with an IR detector could see the illuminator shining, revealing the user’s position.
The Shift to Green: Later Generations
By the 1960s, “Generation 1” (Gen 1) passive night vision emerged. This was a revolutionary change. Instead of projecting their own light, these devices amplified the existing ambient light (starlight, moonlight). This made them much more stealthy. With this new image intensifier tube technology came a new phosphor screen: P43.
The P43 phosphor emits a greenish-yellow light. This color was chosen for very practical, human-factor reasons:
- The human eye is more sensitive to green light and can discern more shades of green than any other color, including red. This allows for better detail recognition and less eye strain.
- Looking at a green screen for extended periods causes less fatigue than staring at a bright red one. Soldiers needed to use these devices for hours on end.
- Green light also appears less bright to potential enemies glancing in your direction, offering a slight tactical advantage.
This green display became the universal standard for all subsequent generations (Gen 2, Gen 3, Gen 4) of night vision goggles and scopes. So, while red night vision is a relic of the earliest technology, the green “night vision” look is a deliberate improvement that has stood the test of time.
Common Misconceptions About Night Vision Colors
It’s easy to get confused about the colors associated with night vision. Let’s clear up a few common points.
Are There Any Modern Red Night Vision Goggles?
True image-intensifying night vision devices (the kind that use tubes) for military or serious civilian use are almost exclusively green. However, you might encounter two things that cause confusion:
- Digital Night Vision: Some consumer digital night vision scopes and goggles let you choose different color palettes (black & white, green, red, etc.) on an LCD screen. This is a software choice, not a phosphor one. The red setting on these is sometimes used to preserve night adaptation.
- Low-End or Toy Devices: Very cheap devices might use a simple infrared LED and a red display screen, mimicking the look of Gen 0 but without the complex tube technology.
What About Thermal Imaging?
This is a crucial distinction. Thermal cameras detect heat, not light. They are a completely different technology. The color schemes on thermal scopes (like black-hot or white-hot) are arbitrary color palettes applied by the computer. A common palette uses red, yellow, and blue to show temperature differences, but this is not “red night vision” in the historical sense at all.
Identifying Generations of Night Vision
If you’re looking at old equipment or footage, you can often guess the generation by its traits. Here’s a simplified guide:
- Gen 0 (Red): Large, bulky units, often with a separate IR spotlight. Distinct red output. Used pre-1960s.
- Gen 1 (Green): Still somewhat large, require some moonlight to work well. Image may be blurry around the edges. The start of the classic green glow.
- Gen 2 & 3 (Green): More compact, much clearer image, can work in very low light. Gen 3 is the current military standard and has superior performance and tube life.
Remember, the shift from red to green was one of the most visible signs of moving from Gen 0 to Gen 1 and beyond. It marked a leap in both stealth and usability.
Why This History Matters for Users Today
Knowing this history isn’t just trivia. It helps you understand the equipment you might be using or buying.
If someone tries to sell you a “military-style” night vision device that has a red output, it is almost certainly using outdated or digital technology. For serious applications, you’ll want a modern image-intensifier tube with a green phosphor screen (typically P43 or P45). The performance difference is night and day—literally.
Furthermore, understanding the active vs. passive distinction is key. Modern passive night vision keeps you hidden. The old active IR systems would give away your position, which is why they were abandoned for infantry use, though they still have some specialized vehicle-mounted applications.
Frequently Asked Questions
Q: Did all old night vision use a red screen?
A: Essentially, yes. All Generation 0 active infrared night vision devices used a red phosphor screen. Earlier models from that era are the ones you see in historical footage with the bright red display.
Q: Why is night vision green instead of red now?
A> Modern night vision uses a green phosphor (P43) because the human eye sees more shades of green, leading to better detail recognition and less eye strain during long periods of use. It’s a practical improvement over the older red phosphor.
Q: Can you get night vision goggles in other colors?
A: True tube-based night vision is almost always green. However, digital night vision devices often offer multiple color palettes on their screen, including black and white, red, or blue. These are software-generated colors.
Q: What generation of night vision is red?
A> The red image is specific to Generation 0 technology. All subsequent generations (Gen 1, 2, 3, 4) produce the familiar green image due to the use of different, more advanced phosphor screens in the image intensifier tube.
Q: Are red night vision goggles better for your eyes?
A: No, in fact the opposite is true. The green phosphor used in modern devices is specifically chosen because it causes less visual fatigue and allows you to see more detail. Red light can be harsh and makes it harder to discern textures and objects over time.
Q: Is the red light from old goggles the same as a red lens flashlight?
A: Not exactly. A red lens flashlight just filters white light to only let red wavelengths through, preserving some night vision. The red in old NVGs was a glowing screen inside the device itself, displaying an electronic image. The function and technology are completely different, though they share a similar color.
In summary, the iconic red night vision goggles are a piece of history. They represent the ambitious begining of a technology that has since evolved dramatically. The shift to the green glow was a direct response to the limitations of the early red systems, prioritizing both the human user’s vision and tactical stealth. So, when you see that green hue in movies or real life, you now know it’s not just a random choice—it’s the result of decades of innovation aimed at seeing clearly in the dark without being seen.