| Topic: |
Science > Physics |
| User: |
"uri" |
| Date: |
22 Jan 2008 11:14:07 AM |
| Object: |
optical discs |
From wikipedia: In sound reproduction, and video, an optical disc is a
flat, circular, usually polycarbonate disc where data is stored in the
form of pits (or bumps) within a flat surface, usually along a single
spiral groove that covers the entire recorded surface of the disc.
My question is: What are pits (or bumps)? What is the "entire recorded
surface of the disc"?
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| User: "" |
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| Title: Re: optical discs |
22 Jan 2008 11:45:04 AM |
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uri <danny99@bezeqint.net> wrote:
From wikipedia: In sound reproduction, and video, an optical disc is a
flat, circular, usually polycarbonate disc where data is stored in the
form of pits (or bumps) within a flat surface, usually along a single
spiral groove that covers the entire recorded surface of the disc.
My question is: What are pits (or bumps)? What is the "entire recorded
surface of the disc"?
pit
n.
1. A natural or artificial hole or cavity in the ground.
2.
a. An excavation for the removal of mineral deposits; a mine.
b. The shaft of a mine.
3. A concealed hole in the ground used as a trap; a pitfall.
4.
a. Hell.
b. A miserable or depressing place or situation.
c. pits Slang The worst. Used with the: "New York politics are the pits"
Washington Star.
5. A small indentation in a surface: pits in a windshield.
6.
a. A natural hollow or depression in the body or an organ.
b. A small indented scar left in the skin by smallpox or other eruptive
disease; a pockmark.
c. Informal An armpit. Often used in the plural.
7. An enclosed, usually sunken area in which animals, such as dogs or
gamecocks, are placed for fighting.
8.
a. The section directly in front of and below the stage of a theater, in
which the musicians sit.
b. Chiefly British The ground floor of a theater behind the stalls.
9.
a. The section of an exchange where trading in a specific commodity is
carried on.
b. The gambling area of a casino.
10.
a. A sunken area in a garage floor from which mechanics may work on cars.
b. Sports An area beside an auto racecourse where cars may be refueled or
serviced during a race. Used with the. Often used in the plural.
11. Football The middle areas of the defensive and offensive lines.
12. Botany A cavity in the wall of a plant cell where there is no secondary
wall, as in fibers, tracheids, and vessels.
bump
n.
1.
a. A blow, collision, or jolt.
b. The sound of something bumping: heard a loud bump in the dark.
2.
a. A raised or rounded spot; a bulge.
b. A slight swelling or lump.
c. Something, such as unevenness or a hole in a road, that causes a bump.
3. A rise or increase, as in prices or enrollment.
4. One of the natural protuberances on the human skull, considered to
have significance in phrenology.
5. A forward thrust of the pelvis, as in a burlesque striptease.
6. Sports A pass in volleyball made by redirecting the ball with the
inside of the forearms, especially when extended and held together.
7. Slang A shot of hard liquor, sometimes accompanied by a beer chaser.
entire
adj.
1. Having no part excluded or left out; whole: I read the entire book. See
Synonyms at whole.
2. With no reservations or limitations; complete: gave us his entire
attention.
3. All in one piece; intact.
4. Of one piece; continuous.
5. Not castrated.
6. Botany Not having an indented margin: an entire leaf.
7. Unmixed or unalloyed; pure or homogenous.
record
n.
1.
a. An account, as of information or facts, set down especially in writing
as a means of preserving knowledge.
b. Something on which such an account is based.
c. Something that records: a fossil record.
2. Information or data on a particular subject collected and preserved: the
coldest day on record.
3. The known history of performance, activities, or achievement: your
academic record; hampered by a police record.
4. An unsurpassed measurement: a world record in weightlifting; a record
for cold weather.
5. Computer Science A collection of related, often adjacent items of data,
treated as a unit.
6. Law
a. An account officially written and preserved as evidence or testimony.
b. An account of judicial or legislative proceedings written and preserved
as evidence.
c. The documents or volumes containing such evidence.
7.
a. A disk designed to be played on a phonograph.
b. Something, such as magnetic tape, on which sound or visual images have
been recorded.
surface
n.
1.
a. The outer or the topmost boundary of an object.
b. A material layer constituting such a boundary.
2. Mathematics
a. The boundary of a three-dimensional figure.
b. The two-dimensional locus of points located in three-dimensional space.
c. A portion of space having length and breadth but no thickness.
3. The superficial or external aspect: "a flamboyant, powerful confidence
man who lives entirely on the surface of experience" Frank Conroy.
4. An airfoil.
disc
n. & v.
Variant of disk.
disk also disc
n.
1. A thin, flat, circular object or plate.
2. Something resembling such an object: The moon's disk was reflected in
the pond.
3.
a. The disk used in a disc brake.
b. A disk used on a disk harrow.
4. A round, flattened, platelike structure in an animal, such as an
intervertebral disk.
5. Botany The enlarged area bearing numerous tiny flowers, as in the
flower head of composite plants, such as the daisy. Also called discus.
6. Computer Science
a. A magnetic disk, such as a floppy disk or hard disk.
b. The data stored on such a disk: read the disk that came with the manual.
7. An optical disk, especially a compact disk. See Usage Note at compact disk.
8. A phonograph record.
9. A circular grid in a phototypesetting machine.
--
Jim Pennino
Remove .spam.sux to reply.
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| User: "uri" |
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| Title: Re: optical discs |
24 Jan 2008 10:16:50 AM |
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The dictionary doesn't say what bumps and pits are in relation to
optical discs. It just gives general definitions. What are bumps and
pits in relation to optical discs?
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| User: "CWatters" |
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| Title: Re: optical discs |
24 Jan 2008 04:19:59 PM |
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"uri" <danny99@bezeqint.net> wrote in message
news:0d469411-dc4a-499f-bea0-8044449ec997@q21g2000hsa.googlegroups.com...
The dictionary doesn't say what bumps and pits are in relation to
optical discs. It just gives general definitions. What are bumps and
pits in relation to optical discs?
Google how a CD is made.
CDs are made from several layers. Pits are projections of one layer into
another.
A pit on a CD is between 0.83 and 3.05 um long. On a DVD its 0.4umm and
0.74um.
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| User: "uri" |
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| Title: Re: optical discs |
25 Jan 2008 05:31:34 AM |
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On Jan 25, 12:19 am, "CWatters"
<colin.watt...@NOturnersoakSPAM.plus.com> wrote:
Google how a CD is made.
CDs are made from several layers. Pits are projections of one layer into
another.
What do you mean by projections? You mean the nanometer-scale
depressions holding the data in a compact disc?
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| User: "" |
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| Title: Re: optical discs |
25 Jan 2008 07:55:03 PM |
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uri <danny99@bezeqint.net> wrote:
On Jan 25, 12:19 am, "CWatters"
<colin.watt...@NOturnersoakSPAM.plus.com> wrote:
Google how a CD is made.
CDs are made from several layers. Pits are projections of one layer into
another.
What do you mean by projections? You mean the nanometer-scale
depressions holding the data in a compact disc?
projection
n.
1. The act of projecting or the condition of being projected.
2. A thing or part that extends outward beyond a prevailing line or
surface: spiky projections on top of a fence; a projection of land
along the coast.
--
Jim Pennino
Remove .spam.sux to reply.
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| User: "uri" |
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| Title: Re: optical discs |
25 Jan 2008 02:15:49 PM |
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On Jan 25, 12:19 am, "CWatters"
<colin.watt...@NOturnersoakSPAM.plus.com> wrote:
Google how a CD is made.
CDs are made from several layers. Pits are projections of one layer into
another.
What do you mean by projections? You mean the nanometer-scale
depressions holding the data in a compact disc?
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| User: "" |
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| Title: Re: optical discs |
24 Jan 2008 03:55:05 PM |
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uri <danny99@bezeqint.net> wrote:
The dictionary doesn't say what bumps and pits are in relation to
optical discs. It just gives general definitions. What are bumps and
pits in relation to optical discs?
It most certainly does.
pit #5
bump #2.a
What is you native language and why haven't you gotten an English to
what ever your language is dictionary?
--
Jim Pennino
Remove .spam.sux to reply.
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