Japanese article about DVD Forum Japan Conference 2007http://www.watch.impress.co.jp/av/do...71004/dvd1.htm
They are discussing a region coding technology for HD DVD that is stronger than that of DVD.
The DVD forum on the 4th, holding DVD Forum Japan Conference 2007. It reported concerning the present condition of the standardization job of HD DVD/DVD.
* Explaining up-to-date trend such as HD DVD and CSS download
Sub-manager [renobo] Japan Sanwa
Sub-manager Kunihiko [renobo] Japan product development laboratory high technology development Sanwa explained the technical sectional meeting which collects the working group of the DVD forum (TCG) concerning activity, reported the update of 3 layers HD DVD-ROM and HD DVD-Video/VR and for China the standardization circumstance etc of HD DVD-ROM.
Concerning the activity of the ad hoc group of TCG affiliation, introducing match such as proposition of profile for load and the record to DVD-R/RW/RAM of HD DVD-Video/VR. Furthermore, with present marketing HD DVD video title, the region cord/code is not granted, there is no restriction in playback every of area, but with the DVD forum examination concerning region control is being advanced. HD DVD-ROM (HD DVD video) the region control technology which is difficult to be torn, unlike DVD concerning the control of the region playback in, is examined. You use simultaneously whether or not,, necessity whether or not with it examines also the fact that you say, that you say.
3 layers Twin of 2 layers HD DVD-ROM and 1 layers DVD-ROM format Rev.1.0 were decided in September as the option book of HD DVD-ROM. Capacity of the DVD-ROM section as for the capacity of 4.7GB and the HD DVD-ROM section becomes 30GB.
Concerning the DVD-ROM section, the same specification as 2 layers Twinformat for the sake of, you say that it can play back with the existing DVD player without problem. In addition, concerning HD DVD-ROM layer, other than of reflectance ratio stipulated modifying has almost followed the structure of existing 2 layers HD DVD-ROM. However, in order BCA (disk specific ID) to record to 3rd layer, you say that you cannot recognize with the present player.
There you have it, the 2 HD DVD layers in a HD DVD TL Twin disc is not compatible with current HD DVD players while the DVD layer is readable.
Also it seems to mention HD DVD TL51 but I don't understand the bolded part, can anyone decipher it?
By the fact that on the one hand, with 51GB HD DVD-ROM where 3 layer everything reaches HD DVD-ROM layer, with improvement of cutting distance, linear density it improves from existing 15GB expanding record capacity around 1 layers to 17GB. But playback margin almost the same as existing HD DVD, you say that because it corresponds to number of layers increase, spherical aberration revision becomes necessary on drive side.
Concerning 3 layer Twin Format already standardization completes. As for 3 layers 51GB HD DVD-ROM, within year Ver.2.0 of last specification decision schedule. In addition, you aim toward 2 time fast option standard of 4 time fast correspondence and 2 layers HD of 1 layers HD DVD-R/RW DVD-R/RW DL and the standardization etc of HD DVD-RAM DL.
"In drive spherical aberration revision becomes necessary"