What is an IR-cut Filter

IR-cut filter is an essential feature in modern security cameras. But what exactly does it do, and why is it so important for clear, accurate images day and night?

Put simply, an IR-cut filter helps a camera capture true-to-life colors during the day and switch to effective night vision when it’s dark. This article explores the purpose and functionality of IR-cut filters in easy-to-understand terms, explaining how they adapt based on lighting conditions to ensure clear and accurate footage.

 

How does it work?

An IR-cut filter is a moving component inside the camera, distinct from the color filters used on smartphones for photos or videos. This filter plays a crucial role in helping the camera accurately capture the colors in front of it.

• During the day, there’s plenty of light to illuminate the surroundings, but camera sensors can detect a broader range of colors, including infrared light than the human eye can. To ensure accurate color reproduction, the IR-cut filter is activated to correct the colors before the camera processes them.
• At night, the IR-cut filter is disabled. However, this alone isn't sufficient for the camera to see in the dark. That’s where infrared LEDs come into play. These lights turn on when dark, thanks to a light sensor that detects low light conditions. The camera also switches to black-and-white mode, enhancing its ability to see objects illuminated by the infrared LEDs.

Below is a demonstration of how IR-cut filter works during day and night. You can toggle the switches to see the effect they can have on the image. Here's what normally happens:

• Day: Infrared LEDs OFF | Color mode
• Night: Infrared LEDs ON | Black and White mode

NOTE: Cameras with Spotlight / Floodlight, when turned activated, will turn off the infrared lights and be on color mode since the spotlights / floodlights helps illuminate the area; just like during daytime.

If the IR-cut filter get stuck resulting to discolored image during the day and dark image at night (despite seeing that the infrared lights are turned on), check this article to help you resolve it: Why Is My Camera Feed Turning Pink or Purple (Discolouration)

 

Why is it getting stuck?

Here are some reasons why IR-cut filter gets stuck:

1. Dust and Debris Buildup: If the camera loses its ingress protection over time, dust and dirt particles can accumulate inside the camera or around the IR-cut filter mechanism, interfering with its movement.

2. Humidity and Moisture Exposure: Cameras placed in high-humidity environments or exposed to moisture may suffer from condensation buildup inside the unit, which can cause components to stick or corrode.

3. Temperature Fluctuations: Extreme temperatures, especially sudden changes, can impact the delicate mechanics of an IR-cut filter. Cold weather can cause components to contract, and heat can warp or expand them, potentially leading to sticking.

4. Mechanical Wear and Tear: Regular wear from continuous use may gradually wear down the internal mechanisms of the filter, especially if the camera switches frequently between day and night mode.

5. Electronic Malfunctions: Electrical faults or software issues can disrupt the communication between the camera's sensors and the IR-cut filter, preventing it from moving smoothly.

 

How can it be prevented?

1. Regular Cleaning and Maintenance
   • Periodically clean the camera exterior, particularly any moving parts, using a soft brush or compressed air to remove dust and debris.
   • Check for signs of dirt buildup around the lens area, as this can be an indicator that the interior may also need cleaning by a professional.
2. Control the Environment
   • Avoid installing cameras in locations prone to high humidity or direct moisture exposure unless the camera is rated for outdoor or all-weather use.
3. Protect Against Extreme Temperatures
   • Install cameras in shaded areas to minimize direct sun exposure, which can prevent overheating.
   • Use weatherproof housings designed to maintain a stable internal temperature if the camera is placed in an area with extreme heat or cold.
4. Update Firmware Regularly
   • Ensure your camera firmware is up-to-date. Manufacturers often release firmware updates that can improve performance and resolve issues related to filter mechanics and other electronic components.
5. Limit Frequent Switching
   • Position the camera to minimize rapid light changes that may cause it to switch frequently between day and night mode, as excessive switching can increase wear on the filter.

 

Conclusion

An IR-cut filter is a small but crucial component in any security camera that needs to perform well both day and night. By automatically adjusting to different lighting conditions, it allows cameras to show true colors during the day and enhance visibility at night. Understanding how this filter works can empower users to make better choices for their security needs, ensuring reliable, around-the-clock protection.