Current Blu-Ray drives and recorders cannot read the LTH BD-R discs. That because the reproduced signal while reading the discs has a LTH (Low to High) polarity. However, new hardware as well as firmware upgrades to existing players/recorders could add support for LTH recording. Panasonic has already released such a firmware update last November for its for its DMR-BW200, DMR-BR100 and the MR-BW900/BW800/BW700 models. Pioneer is also expected to ship the first LTH BD drives in Spring of 2008.

The advantages of the LTH manufacturing technology is that it can be applied without requiring large-scale manufacturing plant investments, allowing for using modified CD-R and DVD-R manufacturing equipment.
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