Most consumer-grade security cameras are equipped with infrared LEDs that allow them to record in the dark. If you are afraid someone might be spying on you, then it is important to know whether you are safe from any spying during the night and whether infrared cameras can see through your curtains.
In this article, we are going to explain to you how infrared cameras work and whether you are at risk of being recorded through curtains.
How infrared cameras work
Before we can know whether infrared cameras are able to see through curtains, we need to understand how they work.
Even though we cannot see infrared light, every object emits waves in the infrared spectrum. Most consumer-grade CCTV cameras are equipped with infrared LEDs that douse the surrounding environment with infrared beams. When those beams hit an object, the object is reflected back to the camera lens, which captures its infrared image and translates it into an image we can actually see.
The problems with infrared cameras
While infrared works just fine for recordings when there is little to no ambient light, infrared cameras are not without their problems. One of the main drawbacks of infrared cameras is that these types of cameras have a limited range, meaning they are not excellent for keeping large areas under surveillance in the dark.
The other problem is that they are also prone to infrared reflections, or IR glare. If the infrared beam gets reflected into the lens, then the image will have bright white spots in certain places or even become entirely unusable.
This happens, for example, when you place an infrared camera at a certain distance from glass. Glass does not let the IR beam pass through. Instead, it reflects it straight back into the camera, resulting in a spotty image.
Can infrared cameras see through curtains?
Most curtains are behind a window, and since infrared beams usually do not pass through glass, it would be impossible for an infrared camera to see through a curtain behind a closed window.
But would it be different if the window was open?
Well, it depends. The short answer is no. Curtains are usually thick enough to stop IR beams. However, it is possible to imagine a scenario where a very light curtain was the only thing keeping you from your neighbors’ watchful eyes. In that case, although it would be very unlikely, it would be possible for an infrared camera to see through the curtains.
Still, you have to keep in mind that, even in our hypothetical scenario, the camera would not have a very large field of view. Even if it could see through your curtains, chances are the camera would not be able to see very far into your house.
Is it possible to use night vision cameras to look through curtains?
While most consumer-grade cameras are not very good at recording through curtains, that does not mean that it is impossible to know what’s going on behind the curtains. Sure, IR beams will not work to see through curtains, but there are other types of night vision that you need to keep in mind.
Types of night vision
There are three main types of night vision: active infrared, image intensification and thermal imaging.
The technology used in most consumer-grade surveillance cameras is active infrared, which we’ve already discussed. As we have seen, active infrared doesn’t work to see through curtains. But what about the other night vision types?
Image intensification is the technology you would find in night-vision goggles. Devices that use this technology have vacuum tubes that amplify existing light thousands of times, allowing users to see in the dark. While this technology is great for pitch-black scenarios, it’s also not great at seeing through curtains.
But thermal imaging could be a problem. Let’s find out why.
Using thermal imaging to see through curtains
Thermal imaging detects the differences in temperature between objects in the foreground and the background. It does not need any type of illumination, and it can even spot temperature differences through walls, assuming the walls aren’t thick enough.
Unless we are talking about very thick curtains, a camera capable of thermal imaging should be able to easily see any human activity going on behind the curtains.
However, this could be prevented by increasing the temperature in the room. While you would need a very hot room for this, you could prevent the camera from spotting any temperature differences inside the room.
An effective way of keeping your privacy
If you are worried about someone potentially spying on you through your curtains, you should be happy to know that the solution is relatively simple. Most camera spying methods can be easily avoided with a closed window and a thick curtain.
If the curtain is thick enough, you can also open your windows. IR beams will not pass through thick curtains, and even thermal imaging sensors might have problems discerning temperature differences behind relatively thick curtains.
Wrap up
By producing infrared beams and recording the reflected light, infrared cameras use infrared LED lights to capture images in dim lighting. These cameras have a narrow field of view and are susceptible to infrared reflections, yet they are helpful for nighttime surveillance (IR glare).
In particular, if the curtains are covering a closed window, it is doubtful that infrared cameras will be able to see through them. In most cases, curtains are thick enough to block infrared radiation.
However, a device known as thermal imaging that measures temperature changes could be able to see through curtains.
It is important to remember that consumer-grade security cameras rarely use thermal imaging cameras because they are often more expensive.