A field emission device includes an insulative substrate, an electron pulling electrode, a secondary electron emission layer, a first dielectric layer, a cathode electrode, and an electron emission layer. The block copolymer is represented by formula, wherein R is acyl amine group, a=20-200, b=5-50; and molecular weights of the ethoxypoly block component and the poly block component respectively range from 1000-5000 and 1000-10000. Line segments are then extracted as assemblies of those of the edge pixels which are continuous on the image and have a same assigned label. The device can also function as an audio transmitter whereby it vibrates the surface onto which it is mounted and can be used for audio trans-10 mission through the structure or noise and vibration reduction by driving the surface out of phase with the vibration received from the structure. Furthermore, a decoder applies a noise filling operation using a manipulated noise filling estimate depending on a harmonic or speech characteristic of the audio signal.