Blu-ray og HD DVD skal leve i sameksisten

Kald det Buzzwords...
men teknisk.. så har Blu ray ikke en "Ekstra"anti scratch lag...
Blu ray har "Kun" 1 lag før man kommer ind til datalaget, for lige under
det 0.1mm tynde og beskyttende lag.. ligger Dataen.

Blu ray er "Nød" til at have dette lag...

Det man skal mere skal bekymre sig om.. er at Blu rays læsehovede
sidder tættere på skiven end en normal CD/DVD og HD DVD afspiller...
hvilket betyder.. at der er større sansynlighed at læsehovedet vil komme i
kontakt med skiven ved rystelser.
på det punkt vil jeg hellere have risser på skiven.. end risser på
læsehovedet...

---
DVDTimes: I think I heard something about Blu-ray discs - I don't know if
you know about the difference between the two precisely - is it true that
HD DVD would have greater resistance against scratches? Am I right in
saying that on the Blu-ray disc, the data is in a different place?
Jim Armour, Toshiba: Well, actually, if you look at the structure of a Blu-
ray disc, it's actually 1.1mm thick acro, like a CD. Then you have 0.1mm
hard coating on top of that. And the data is actually RIGHT under the
0.1mm hard coating - it's actually more or less steamed onto the
polycarbonate under this hard coating. So, the focus of a DVD lens, once
you get through the polycarbonate material, it actually focuses 0.1mm
onto the actual data layer. The problem with Blu-ray is that the lens is
actually positioned 0.1mm above the physical disc. This protective layer
on the top of the Blu-ray disc is 0.1mm thick, and is very hard -
extremely hard material. It's a very solid carbon material, but transparent.
Now, I only know one nearly transparent carbon material, and that's
diamond - so, nearly as hard as diamond, very close to diamond. And,
the glass lens only floating 0.1mm above it. 0.1mm is about the thickness
of four A4 pages of normal paper. So, the reason they made this coating
very hard, of course, is because if something hits it, it shouldn't scratch.
It can only focus 0.1mm under the surface of the media, where the data
is. If you get a scratch, a fingerprint, or a hair, it's going to be unreadable.
That's why they made it this way.

DVDTimes: I've also heard that the protective layer is part of the trouble
the Blu-ray camp is having in getting the dual-layer discs to work.
Jim Armour, Toshiba: That's exactly correct, because the second layer.
The lens on the BD system has a numerical apeture of 0.85. This means
that the light cone that's focusing on the disc underneath it, is very wide.
It's like the difference between a normal ice-cream cone, and spreading
out the top of an ice-cream cone to five times it's physical diameter, and
then shortening the length of the cone by about four. So, you've got a
very wide cone, focusing on this thing, and it's only going a tiny bit into
the media, so if you have dirt or dust or a scratch, or anything like that
[...] you're going to have a problem. This is why they had to make it very
hard, and they also had to make it fingerprint resistant, so it would repel
oil.
DVDTimes: I think in the early days in Japan, they originally had it in
cartidge?
Jim Armour, Toshiba: They did, exactly. This is before they put on the
hard coating. Blu-ray really needs the hard-coating, but HD DVD doesn't,
because our lens is sitting 1mm above the media, and it's focusing
0.5mm into the media, it's focusing right through the media, so we can
get a better signal back.
DVDTimes: So basically, HD DVD is more resistant...
Jim Armour, Toshiba: It's more resistant, and more physically reliable.
But, the Blu-ray guys [...] they haven't coated the lens with an ultra-hard
material, so if the ultra-hard material hits the glass lens, you're going to
scratch the lens - then you won't be able to read anything.
---
Snuppet fra dette interview:
http://www.dvdtimes.co.uk/content.php?contentid=62615




Redigeret af GrillBiller - 25-September-2007 kl. 21:15

GrillBiller skrev: Kald det Buzzwords... men teknisk.. så har Blu ray ikke en "Ekstra"anti scratch lag... Blu ray har "Kun" 1 lag før man kommer ind til datalaget, for lige under det 0.1mm tynde og beskyttende lag.. ligger Dataen. Blu ray er "Nød" til at have dette lag... Det man skal mere skal bekymre sig om.. er at Blu rays læsehovede sidder tættere på skiven end en normal CD/DVD og HD DVD afspiller... hvilket betyder.. at der er større sansynlighed at læsehovedet vil komme i kontakt med skiven ved rystelser. på det punkt vil jeg hellere have risser på skiven.. end risser på læsehovedet... --- DVDTimes: I think I heard something about Blu-ray discs - I don't know if you know about the difference between the two precisely - is it true that HD DVD would have greater resistance against scratches? Am I right in saying that on the Blu-ray disc, the data is in a different place? Jim Armour, Toshiba: Well, actually, if you look at the structure of a Blu- ray disc, it's actually 1.1mm thick acro, like a CD. Then you have 0.1mm hard coating on top of that. And the data is actually RIGHT under the 0.1mm hard coating - it's actually more or less steamed onto the polycarbonate under this hard coating. So, the focus of a DVD lens, once you get through the polycarbonate material, it actually focuses 0.1mm onto the actual data layer. The problem with Blu-ray is that the lens is actually positioned 0.1mm above the physical disc. This protective layer on the top of the Blu-ray disc is 0.1mm thick, and is very hard - extremely hard material. It's a very solid carbon material, but transparent. Now, I only know one nearly transparent carbon material, and that's diamond - so, nearly as hard as diamond, very close to diamond. And, the glass lens only floating 0.1mm above it. 0.1mm is about the thickness of four A4 pages of normal paper. So, the reason they made this coating very hard, of course, is because if something hits it, it shouldn't scratch. It can only focus 0.1mm under the surface of the media, where the data is. If you get a scratch, a fingerprint, or a hair, it's going to be unreadable. That's why they made it this way. DVDTimes: I've also heard that the protective layer is part of the trouble the Blu-ray camp is having in getting the dual-layer discs to work. Jim Armour, Toshiba: That's exactly correct, because the second layer. The lens on the BD system has a numerical apeture of 0.85. This means that the light cone that's focusing on the disc underneath it, is very wide. It's like the difference between a normal ice-cream cone, and spreading out the top of an ice-cream cone to five times it's physical diameter, and then shortening the length of the cone by about four. So, you've got a very wide cone, focusing on this thing, and it's only going a tiny bit into the media, so if you have dirt or dust or a scratch, or anything like that [...] you're going to have a problem. This is why they had to make it very hard, and they also had to make it fingerprint resistant, so it would repel oil. DVDTimes: I think in the early days in Japan, they originally had it in cartidge? Jim Armour, Toshiba: They did, exactly. This is before they put on the hard coating. Blu-ray really needs the hard-coating, but HD DVD doesn't, because our lens is sitting 1mm above the media, and it's focusing 0.5mm into the media, it's focusing right through the media, so we can get a better signal back. DVDTimes: So basically, HD DVD is more resistant... Jim Armour, Toshiba: It's more resistant, and more physically reliable. But, the Blu-ray guys [...] they haven't coated the lens with an ultra-hard material, so if the ultra-hard material hits the glass lens, you're going to scratch the lens - then you won't be able to read anything. --- Snuppet fra dette interview: http://www.dvdtimes.co.uk/content.php?contentid=62615

 

Fra Toshiba!!! Hvor meget skulle det være værd?

 

du kan finde alle tekniske detalier om Blu ray på nettet.. og de viser præsis
det de beskriver...

ja egentligt mærkligt.. når HD DVD lægger oven på Blu ray på amazon sale
range og ligger pænt parallelt med hvad salget angår.

og engang om ugen skifter plads på Axelmusic.com "Format War" rank.
jeg ville heller ikke mene at Nielsen VideoScan viser 2:1 mere... sårn som
dengang BDA først kom frem med de resultater...

Hvilket jo er meget pænt.. når man tænker på at HD DVD "kun" har 2
eksklusive udgivere.. at de kan ligge så tæt på Blu ray...

så tidlig som i torsdags hed den 47:53...

De vælger det der er billigst...

Eller det produkt som sælgeren får Provision for...