Disclosed is a display device using a demultiplexer. In various embodiments, samples are grouped into one or more blocks. The alignment member preferably includes at least one sloped surface which slopes toward at least one seating adapted to seat the at least one fitting of the instrument assembly. A plurality of segments is generated from the media timeline for sequential rendering such that each segment references a particular set of the timeline objects that are rendering during a duration of the segment. This allows the desired sound data to be retrieved on the basis of the subjective impression of the user on the sound data. The converging optical system comprises an objective lens to converge a first or second light flux having passed through the coupling lens on a first or second optical information recording medium; and a diffractive structure to change a focal length in accordance with a wavelength of a light flux emitted from the first light source or the second light source.