We've previously shared many black wallpaper series. Here, let me explain why there's such a strong preference for black, along with the scientific principles and design considerations behind it.
Phone screens are mainly divided into OLED (Organic Light-Emitting Diode) and LCD (Liquid Crystal Display).
1️⃣ Display Principles OLED: Each pixel consists of organic light-emitting diodes (OLEDs), which emit light at different colors and brightness levels to create images. OLED pixels only light up when current passes through them, so displaying black consumes no power.
LCD: LCDs use liquid crystals to control light transmission. They require a backlight to illuminate the liquid crystal layer, and the LCD molecules control the light transmission degree via an electric field, so displaying black still consumes power.
2️⃣ Contrast and Color Performance OLED: OLEDs can achieve very high contrast because black pixels can be completely turned off while other colors can be very bright.
LCD: LCDs typically have lower contrast because even when the liquid crystals are fully off, the backlight still passes through the liquid crystal layer. Additionally, LCD displays have relatively poor color performance, especially in black and dark color displays.
3️⃣ Dark Mode Apple first used OLED screens on the iPhone X released in 2018, and since then, the 11 to 15 series have adopted OLED screens. (Except for iPhone XR, iPhone 11, and SE series, which use LCD screens.)
Therefore, it is recommended for iPhone users to enable the "Dark Mode" in the iOS system by going to "Settings-Display & Brightness-Appearance." Many apps have also adapted to this mode, turning UI interfaces into dark colors, which along with black wallpapers, achieves even greater power savings and is more eye-friendly in low-light environments.
