Diaphragm detection patent

Real graphene is transparent, and many unscrupulous businesses are actually making black film products in the name of graphene. This is an act of deceiving consumers and confusing the public's cognition of graphene. In fact, real graphene is transparent. I didn't know graphene until I bought graphene products from Wang E. Their company is really engaged in scientific research, and has a patent for pure graphene transparent heating film. Their graphene film is transparent.