US Patent 10142719 Microphone

A microphone includes a head case and an arm that supports the head case. The head case includes a microphone unit and a light emitter. A proximal end portion of the arm includes a light emitter circuit that turns on the light emitter on the basis of potential information of a specific terminal. One end of the light emitter is connected to the light emitter circuit through a wire that passes through an inside of the arm. The other end of the light emitter is connected to the microphone unit in the head case. The light emitter circuit includes a switching element that switches on and off of light emitter. The specific terminal is connected to a control signal input side of the switching element.