Ambient light sensor An ambient light sensor measures the amount of light in your surroundings and tweaks your phone's brightness based on that (if it's set to automatic brightness).

If you’re curious about how traffic light sensors work, or just want to keep the flow of green lights and good vibes rolling, here’s what to know.

Outdoor light motion sensors can add a healthy level of security to your home. Here's how to set them up.

It just uses an IR LED and some fancy optics. How it Works The simple explanation for how these sensors work is that they bounce light off a target and measure how long it takes to see the reflection.

Ambient light sensors can reveal your device activity. How big a threat is it? For now, there's no reason for concern, but that could change in coming years.

Commercial hydrogen sensors only work at temperatures of 150C or higher, but the prototype developed by researchers at RMIT University in Melbourne, Australia, is powered by light instead of heat.