Patent ID: 8264927
Filing Date: 2012-09-11
Classification: G11B

Abstract:
1. A write-once information recording medium, which has at least one recording layer and on which information is written on a block-by-block basis, wherein the write-once information recording medium comprises: a user data area on which user data is going to be written; and a management information area to store management information about the write-once information recording medium, and wherein the user data area is provided for each said recording layer, and wherein the management information comprises: a space bitmap including bitmap information for use to manage recording statuses in the user data area on a predetermined one recording layer of the at least one recording layer; and a disc definition structure including location information of the space bitmap, and wherein the size of the space bitmap is determined so that the combined size of the space bitmap itself and the disc definition structure always becomes equal to that of one block, irrespective of the size of the user data area, and wherein the size of the user data area on the predetermined one recording layer exceeds a predetermined size, the predetermined size is a maximum size of the user data area that can be managed by one piece of bitmap information multiple space bitmaps are generated for the user data area of the predetermined one recording layer, and wherein a disc management structure update unit, including one of the multiple space bitmaps and the disc definition structure and having a size of one block, is written on the management information area.