Luis Rojas Estudio/Shutterstock With smartphones, computers, and TVs being ubiquitous in modern life, digital eye strain (DES) has become a real concern. Symptoms of DES include irritated eyes, blurry vision, and light sensitivity, and they are likely to show up after staring at screens continuously for two or more hours. Activities that can lead to excessive screen time include doom scrolling, high-intensity gaming sessions, remote work, and reading books using e-readers . Ophthalmologists and other eye experts have long recommended a simple eye care technique called the 20-20-20 rule as an effective way to prevent or ease eye strain. The rule is simple: For every 20 minutes of screen time, look at an object 20 feet away for 20 seconds. Since screens are usually placed at a close viewing distance, this causes the eye muscles to contract to keep things in focus (they relax when looking at distant objects).…