Bought a new monitor ? Worrying on backlight bleed ? lack screen to test your brand new monitor, laptop or phone, simply use our full screen dark background to diagnosis the display issues. Black screen is a seemless solution to test backlight bleed. A pure black screen can detect the dead pixels, screen burn-in, and color discolorization of your display panel. If you see the blank blank screen without any spots on the in AMOLED and OLED devices. You shall have the best viewing experience once you finish your pixel test easily .