Write-once information recording medium, information recording apparatus, information recording method, information reproducing apparatus and information reproducing method

An information writing apparatus for writing information on 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 of the recording layers;
• 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 if the size of the user data area on the predetermined recording layer exceeds a predetermined one, the information writing apparatus generates multiple space bitmaps for the user data area of the predetermined recording layer, and writes 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, on the management information area.

An information writing method for writing information on 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 of the recording layers;
• 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 information writing method comprises the steps of:
• if the size of the user data area on the predetermined recording layer exceeds a predetermined one,
• generating multiple space bitmaps for the user data area of the predetermined recording layer, and
• writing 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, on the management information area.

An information reading apparatus for reading information from 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 of the recording layers;
• 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 if the size of the user data area on the predetermined recording layer exceeds a predetermined one, multiple space bitmaps are generated for the user data area of the predetermined recording layer, and
• 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, and
• wherein the information reading apparatus reads the disc management structure update unit, including the disc definition structure and having a size of one block, from the management information area and obtains the space bitmap.

An information reading method for reading information from 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 of the recording layers;
• 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 if the size of the user data area on the predetermined recording layer exceeds a predetermined one, multiple space bitmaps are generated for the user data area of the predetermined recording layer, and
• 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, and
• wherein the information reading method includes the step of reading the disc management structure update unit, including the disc definition structure and having a size of one block, from the management information area and obtains the space bitmap.