A first substrate includes a coil assembly and an integrated circuit mounted thereon. The display medium is included in an electrophoretic display device by including the medium in a multiplicity of individual reservoirs of a display layer or layers that is located between conductive substrates. By the arrangement, optically assisted magnetic recording can be performed, small size and light weight are achieved, and higher transfer rate can be implemented. The compounds have formula :wherein R1, R2, n, and m have the meanings given in the specification. The driving transistor is also configured to drive the outputting transistor according to the control signal.