A dulling assembly includes a corrugated bundle having a plurality of generally vertically oriented planar paperboard sheets with fluted paperboard sheets located therebetween, each fluted paperboard sheet being adhered to the two planar paperboard sheets it is located between, and a plurality of grains of sand adhered with glue to a top surface of the corrugated bundle. The first n-type semiconductor layer has a first n-type surface region and a second n-type surface region. In the encoder, an encoding rate setting unit sets an encoding rate s, and an information creating unit sets information including from information Xs,i to information Xz\u22121,i to zero.