Elastomeric mirror is one of the main components of systems that require tunable optical characteristics, and is being applied in various devices such as optical zoom camera, electrostatic actuator, and augmented/virtual reality (AR/VR) display. Generally, to fabricate an elastomeric mirror, a metal layer is deposited on an elastomer substrate by vacuum process such as thermal evaporation, e-beam evaporation, and sputtering. However, these processes can damage the elastomeric substrate, thereby degrading the quality of the mirror surface. The metal layer formed on the elastomeric substrate is also vulnerable to small deformation, which limits applications of elastomeric mirror. In this work, we report all-solution-processed elastomeric mirror film whose constituent layers were deposited sequentially by spin coating and dip coating method. The film consists of polydimethylsiloxane (PDMS) base, aluminum (Al) mirror, and PDMS encapsulation layer. As a material of mirror layer, we selected a ‘mirror ink’, which composed of Al powder, organic solvent, adhesive and mainly used for screen printing. We adjusted the dilution concentration of mirror ink to make it suitable for the solution process and controlling the roughness of the coated mirror layer. In addition, there was no damage to the mirror layer against deformation due to the presence of encapsulation layer, so it can be attachable well to the curved surface. As an example of application, we demonstrated a seamless display system by placing the elastomeric mirror between two curved panels. We expect that our elastomeric mirror will be applicable to various tunable optical systems.
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