▎ 摘　　要

NOVELTY - A grapheme-based filter comprises filter unit, where the filter unit comprises a second optical window laminated in a laminating direction of the graphene layer, metal electrode layer, the ionic liquid layer and the first optical window. USE - Grapheme-based filter for use in optical engineering applications and optical instrument. ADVANTAGE - The grapheme-based filter can be prepared with low power consumption in convenient manner. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a grapheme-based filter.