Berkeley CSUA MOTD:Entry 38152
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2018/11/14 [General] UID:1000 Activity:popular
11/14   

2005/6/16-18 [Computer/HW/Drives] UID:38152 Activity:nil
6/16    I've been hearing a lot about something called a perpendicular
        hard drive, but I can't seem to figure out what the big deal
        is? Anyone know why these drives are interesting (as compared
        w/ regular hds)?
        \_ Perpendicular recording.  Imagine that a regular HDD has the bits
           represented by lots of coins flipped to heads or tails, laid out in
           rings on a platter.  Now imagine if you could stand the coins on
           edge and still read what direction heads and tails are.  You can
           pack the coins in a much higher density.  The coins in this example
           represent magnetic domains in a hard drive.
           \_ ic, thanks
           \_ I've heard this before, I understand they've been
              researching this for 20 years or something.  Is it really
              viable?
              \_ Nevermind, I guess Seagate and Hitachi came up with a way
                 to do it.
                 \_ Wow.  That slipped under my radar.  Where's /. poster guy?
           \_ Here's a fun flash animation (you really need sound)
              http://www.hitachigst.com/hdd/research/recording_head
              /pr/PerpendicularAnimation.html
2018/11/14 [General] UID:1000 Activity:popular
11/14   

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Cache (1973 bytes)
www.hitachigst.com/hdd/research/recording_head -> www.hitachigst.com/hdd/research/recording_head/
how to buy Search by Google Go Recording Head Overview The Recording Head Research Department is responsible for fundamental res earch and development in magnetic materials and structures which will le ad to magnetic read/write heads used in Hitachi's latest high capacity/h igh performance disk drive products. Understanding the basic science of recording at areal densities approaching 200 Gbits/in2 and beyond is a p rincipal charter of this group. The team has played a key role in advanc ing areal density growth to its present 100 % per year with the introduc tion of the giant magnetoresistive read sensors in a 1997 disk drive pro duct and since that time IBM has continued leadership in areal density w ith each new product announcement. IBM has traditionally played a leader ship role in the introduction of new head technologies; from inductive r ead/write heads in 1978, MR read/inductive write heads in 1991, to today 's GMR read/inductive write heads. IBM first demonstrated the GMR effect in a thin film structure at room temperature and this lead to the prese nt spin valve read head design which has subsequently become and industr y standard, essentially replacing the previous MR technology. The group has been pivotal in developing new head technologies that enabl e demonstrations of progressively higher areal densities in a laboratory environment and establish the capabilities of recording heads for advan ced products. This team is continuing leading edge research in advanced inductive structures for writing high coercivity disks at operating freq uencies approaching 1 GHz and in advanced read sensors by extending GMR sensors as well as by developing new magnetic tunnel and CPP sensor tech nologies required for areal densities exceeding 200 Gbits/in2. These advanced head structures are considered to be candidates for new an d innovative types of magnetic recording which could be radically differ ent from today's head and media technology.