A rollable display device includes a display panel for displaying an image, a printed circuit board connected to an edge of the display panel, and a roller which the display panel is rolled onto or unrolled from. The roller has a cylindrical shape having an inner space, and the printed circuit board is disposed in the inner space.

An apparatus (1) for controlling the unwinding of a web (2) wound on a core is disclosed. The apparatus (1) includes a turnbar (10), an actuator (20), a sensor (30), and a controller (70). The turnbar (10) includes a target location to receive the web (2). The actuator (20) is coupled to the turnbar (10) and includes an axis of movement (29). The sensor (30) measures transverse placement of the web (2) relative to the target location and transmits an input signal to the controller (70) when transverse placement of the web (2) differs from the target location. The controller (70) provides an output signal to the actuator (20 to move the turnbar (10) along the axis of movement (29) such that the web (2) maintains substantial alignment with the target location.

An image forming apparatus is provided that is aimed to control adverse impacts on a printing quality caused by the meandering motion of a printing belt and changes of a feeding speed. The image forming apparatus includes: one or more printing portions that print a printing object on paper; a belt in a form of a loop, the belt serving to transport the paper to a printing position; a roller that feeds the belt; a phase detector that detects a phase of the belt; a behavior detector that detects a behavior of the belt; a controller that decides a paper setting position on the belt based on the behavior of the belt for each phase; and a paper feeder that transports the paper to the paper setting position.