In an interpolation device that is used for driving a liquid crystal display (LCD), a memory stores an image signal representing a previously displayed image frame. A look-up table (LUT) stores plural reference data corresponding to differences between values of high order bits of a present image signal and a previous image signal. An arithmetic unit receives low order bits of the present image signal, low order bits of the previous image signal, and the reference data from the LUT to output a corrected image signal. The arithmetic unit applies a first second-order interpolation equation when the high order bits of the present image signal are identical to the high order bits of the previous image signal and applies a second second-order interpolation equation, which is different from the first second-order interpolation equation, when the high order bits of the present image signal are different from the high order bits of the previous image signal.