▎ 摘　　要

NOVELTY - The filter has a sandwich structure layer that is located on a substrate layer (1). The sandwich structure layer includes a first graphene layer (2), a hexagonal boron nitride layer (3) and a second graphene layer (4) from bottom to top. One end of the first graphene layer has a first extension (21). The surface of the first extension is plated with a first metal film (22). One end of the second graphene layer has a second extension (41). The surface of the second extension is plated with a second metal film (42). A cladding (5) is located on the sandwich structure layer. USE - Mid-infrared voltage adjustable filter. ADVANTAGE - The mid-infrared voltage adjustable filter filters in the mid-infrared band, and filters out the interference signals such as noise signals in the space, allows some waves in the mid-infrared band to pass, and avoids the interference signals from adversely affecting the information transmission. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method of manufacturing a mid-infrared voltage adjustable filter; and (2) a filtering method of the mid-infrared voltage adjustable filter. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the mid-infrared voltage adjustable filter. (Drawing includes non-English language text) Substrate layer (1) First graphene layer (2) Hexagonal boron nitride layer (3) Second graphene layer (4) Cladding (5) First extension (21) First metal film (22) Second extension (41) Second metal film (42)