Abstract: The knob screen device includes a glass touch cover plate, a display screen, a screen support frame, a semi-transparent turning structure, an annular light-leading friction shim, at least one battery, a mainboard and a magnetic attraction assembly. The knob screen device further comprises: at least one Hall sensor provided on the mainboard; at least one multicolor LED ambient light provided on the mainboard; and at least one annular multipolar flexible magnet provided in the semi-transparent turning structure. The semi-transparent turning structure is connected to external component by means of the magnetic attraction assembly. In this way, the knob screen device is simple in structure, low in cost, easy to process and install and more flexible in application circumferences.