How to See Infrared Light with Your Phone: 1 Minute to Uncover Hidden Light Sources

Many people are curious about the hidden world of infrared (IR) light, especially considering how crucial it is in remote controls, security cameras, and night vision technology. While our human eyes can't detect infrared light, most smartphone cameras are sensitive enough to pick it up. Here’s how you can use your phone to “see” infrared light, plus tips to ensure accurate results—and a designer's take on using this knowledge creatively in your living spaces.

How to See Infrared Light with Your Phone

1. Grab Any IR Remote: Find a device like a TV or AC remote control. These remotes use IR LEDs to send signals you can’t normally see.
2. Open Your Phone Camera: Open your phone’s default camera app. Note: Some newer phone cameras have stronger infrared filters on the main lens, so if this method doesn’t work, try the selfie (front-facing) camera, which often has a looser filter.
3. Point the Remote at the Camera: Hold the remote’s LED (usually at the tip) facing the camera lens. Make sure you can see the LED on your phone’s screen.
4. Press a Button: While watching through your phone screen, press any button on the remote. You’ll likely see a flashing white or pinkish light on your device’s display—this is infrared light being picked up by your camera sensor!
5. Test Other Devices: Try this technique with other unknown LEDs or small bulbs to see if they're IR-based. Some security sensors and smart home devices use IR, and this trick can help troubleshoot them.

Why This Works

Smartphone cameras, like most digital sensors, are sensitive to a range of wavelengths beyond the visible spectrum. Although many manufacturers add filters to cut down on infrared sensitivity (to improve color accuracy), some IR light still slips through.

Designer Perspective: Using Infrared Sensitivity Creatively

As a designer, understanding your environment’s lighting—including the invisible kind—can inspire unique design solutions. For example, if you want to integrate hidden smart sensors or accentuate artwork with selective lighting, testing with your phone camera helps ensure IR devices are invisible to the eye but "visible" for smart controls. Leveraging tools like a 3D Render Home helps you visualize natural and artificial lighting scenarios, guiding optimal sensor placement and achieving not just comfort but elegance in lighting design.

Tips 1:

- If you can’t see the IR light, try a different phone or the selfie camera. - For an even cooler experience, try filming IR remote flashes in a dark room for a more dramatic effect. - Use this trick to check if your remote controls need new batteries—the IR light might be faint or absent if the battery is low! - Be mindful that not all phone models respond equally well due to hardware differences.

FAQ

Q: Why can’t humans see infrared light but cameras can?

A: Human eyes are sensitive only to the visible light spectrum (about 400–700nm). Digital cameras can pick up slightly wider wavelengths, including some infrared, especially if there’s no strong IR filtering.

Q: Do all phone cameras detect infrared light?

A: Most do, but some newer models add strong IR filters to improve photo quality. If it doesn’t work with your main camera, try the selfie camera.

Q: Can this method damage my phone camera?

A: No, observing or photographing IR light from remotes or home devices won’t harm your camera.

Q: What other uses does IR detection have at home?

A: Beyond troubleshooting remotes, you can check IR-based smart home sensors or set up “invisible” lighting arrangements as part of your home’s functional decor.

Q: Can I see thermal imaging this way with my phone?

A: Standard phone cameras detect near-infrared, not the far-infrared spectrum used for heat (thermal) imaging. For that, you'd need a special thermal camera accessory.