In recording audio information, an information medium in a format obtained by expanding the RTR standard is used. An antiferromagnetically coupled layer pair is disposed between the first and second data layers. The converted block vector image is stored in a storage means. The statistics server aggregates the statistical data from the plurality of servers in an optimized staggered manner during a recurring interval. The collapse allows the system to extend and force open the fingers to disengage the second member from the first member.