Electromagnetic flapping shutters for phone camera applications

We present the small-size, low-power, and high-speed electromagnetic flapping shutters, composed of the butterfly-wing shaped twin blades suspended by H-type torsional springs for phone camera applications. The present electromagnetic flapping shutters are designed to use the low-inertia trapezoidal twin blades, each suspended by the low-stiffness H-type torsional springs. In the experimental study, the electromagnetic flapping shutters generate the steady-state rotational angles of 53.9 ± 1.6° and 70.3 ± 1.6° in the magnetic fields of 0.15 T and 0.30 T, respectively, for the input current of 80 mA, while achieving the maximum overshoot angles of 84.5 ± 3.8° and 90.0 ± 1.0° in the magnetic fields of 0.15 T and 0.30 T, respectively. The shutter shows the rising/settling times of 1.0 ms/20.0 ms for opening, while showing those of 1.7 ms/10.3 ms for closing. Therefore, we experimentally demonstrated that the small size (4 × 6 × 0.5 mm
³
), low power (<80 mA), and high speed (~1/370 s) electromagnetic flapping shutters are suitable for phone camera applications.