rina-chan board
The sketchbook or digital mask used by Tennoji Rina from Love Live! Nijigasaki High School Idol Club.
Rina is not good at conveying emotions on her face. Because of this, she makes use of the "Rina-chan Board", a sketchbook that she draws her emotions on.
Another variation is the "Auto Emotion Convert Rina-chan Board", a digital pixel mask that uses a dot-matrix display that instantaneously reacts to her emotions on the fly without having to read her face, and is capable of emulating lip movements accurately, useful on stage and other activities that require both hands.