The camouflage of a squid use a transformable skin which have a capability to switch from transparent to opaque skins and vice versa. The mechanism is known that the muscle of a suqid can control the size of light absorption dyes. In this presentation, we demonstrate a new concept of smart window by mimicking the squid skin. We use magnetic nanoparticles dispersed within pyramidal structures and modulate the area of light absorption by chaning the position of the magnetic field. We show the change of transparency difference (ON/OFF ratio) by controlling the concentration of magnetic nanoparticles and the dispersive liquid and provide a simple model to explain. In addition, we propose a better structure design for higher transmittance and demonstrate the performance by using 3D printing technology.