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Design and Implementation of Portable Visual Stimulator for BCI

Visual stimulator is one of the key factors that affect the steady-state visual evoked potential (SSVEP). Research and development of brain-computer interface (BCI) system based on SSVEP have priority to consider the design and implementation of visual stimulation. Compare with visual stimulators for particular applications, this paper presents a visual stimulator that is portable and easy to modify apparatus, which is suitable for expanding the application of SSVEP based BCI system. This article induces a visual stimulator based on ARM microcontroller for BCI. The stimulator uses a common USB interface, achieving multiple selective stimulus methods. The system features include visual stimulation, parameter setting and display, the experimental results feedback display. Experimental data prove that this stimulator can be used for almost all types of brain-computer interface based on visual stimulation experiments, and have a portable operating mode, flexible parameter settings , and easy operation.