It’s 11:37 p.m. You finally push out the final paragraph of your essay due at midnight. Your eyes flicker across the bright glare of your laptop screen. With a triumphant sigh, you submit your assignment and shut your laptop. You turn off the lights. Before your eyes can take comfort in any respite, you jump into bed and immediately grab your phone. You scroll through your social media platform of choice, your face illuminated in the dark.
We are staring at screens now more than ever. A 2018 Nielsen study found that adults spent over 11 hours a day looking at screens. Screen time often continues late into the night. Software developers are racing to provide the latest trendy solution to satisfy consumer demand for this behavior: dark mode. Students are switching to the dark side.
“I use it for all devices, but mainly for email and reading long bouts of text,” said fourth-year mechanical engineering major Gavin Anderson. “I just feel like it is easier on my eyes and also kinda makes me less fatigued over time. It also kinda makes me feel like a secret agent and I like that vibe.”
Others simply prefer a refreshed look for their devices.
“I just like that it’s different from what it has been for the past 10 years,” fourth-year business major Emma Kanchanawat said. “It makes the interface sleeker. It’s kind of like how they now have space gray laptops. A lot of people are buying them because it’s different from just the silver. People are leaning toward the minimalist, darker look.”
MacOS Mojave and Catalina, iOS13, Windows 10, Android 10, and many individual apps all offer dark mode options, which shifts the overall look of the interface from traditional light backgrounds with dark text to the inverse. Many love the modern, high-contrast look. But software providers often pitch this option as a battery saver as well as an ideal setting for “low-light environments” (such as scrolling through Instagram in bed with the lights off). But does any of this stand? Yes and no.
Dark mode does notably increase battery life, but only for OLED (organic light-emitting diode) screens, according to Forbes. In dark mode, certain pixels actually turn off in OLEDs in dark mode, greatly reducing power needs. However, for LCD (liquid crystal display) screens, all pixels are always lit, so the power consumption remains the same. Check to see what type of display your phone or laptop has. The iPhone 11 Pro, iPhone X, iPhone Xs, Samsung Galaxy S series, and new Google Pixel phones have OLEDs. Note that the iPhone 11 and iPhone Xr and the vast majority of laptops have LCDs. Right now, most devices are unable to support the battery benefits of dark mode, but as OLEDs become more common, this will change.
Screens emit a lot of blue light. Contrary to popular belief, blue light itself has not been proven to actually cause eye damage. Computer vision syndrome, which causes eye strain, stems from the tendency to not blink enough while looking at screens, reflections and glares off of monitors, and screen “flickering” due to monitor refresh rate — not because of the screens’ blue light itself.
However, Harvard Health states that too much exposure to blue light at night does impact circadian rhythms and worsens quality of sleep. There has long been a tool to mitigate this effect, often called “night mode” or “night shift.” This feature is offered in most smartphones and computers. When enabled, it automatically shifts the screen display to a warmer tone at night in order to reduce blue light. Some dark mode critics argue that because of the existence of night mode, dark mode is an extraneous and unnecessary solution to the blue light problem.
There’s another issue: A common user interface design principle is to avoid white text on a black background, which is the norm for dark mode. An Android Authority article breaks down why: Our irises do not need to absorb more light to read standard dark text on a white background. This means they don’t widen. However, “When you see light text on a dark screen, the edges of it seem to bleed into the black background.” Our irises need to widen, increasing effort to distinguish and read the words.
Additionally, Gizmodo reports (citing the Sensory Perception and Interaction Research Group at University of British Columbia) that if you have astigmatism — irregular shape of one or both eyes that half the population suffers from — it will be even more difficult to read white on dark text. When the iris widens, the eye’s irregular shape exacerbates troubles with focusing.
Should you use dark mode? If you have astigmatism, probably not. Unless you have an OLED screen, dark mode likely won’t be saving precious battery life. It probably won’t single-handedly save your eyes from the strain of staring at a screen all day. It may be fair to say that dark mode is a bit overhyped. However, if you do think it’s easier on your eyes, or you just want to feel like a secret agent when scrolling through your Husky mail, then go ahead and switch it on.