LG GCE 8480B Service Manual page 6

ATIP Absolute Time In Pre-groove.With an additional modulation of the "Wobble",the "Groove" contains a
time code information
Wobble The pre-groove in the Disc is not a perfect spiral but is wobbled with ; - a typical amplitude of 30ns
(Pre-) groove The guidance track in which clocking and time code information is stored by means of an FM
modulated wobble
CW Continuous Wave. The laser light output is at a constant level
DOW Direct Over-Write. The action in which new information is recorded over previously recorded
information in CD-RW disc.
Overwrite The action in which new information is recorded over previously recorded information
Land Land is characterized in the following way:
When radial signals are concerned,land is defined as the area between the groove
When HF signal are concerned,land is defined as the area between the marks(pits) in tangential
direction
Hybrid Disc A Multisession disc of which the first Session is mastered. On a hybrid disc, recorded and mastered
information may co-exist
Mastered Information Information,stored as pits on the disc during the manufacturing process of the disc (when making the
"master")
OPC Optimum Power Control. Procedure is determined optimum recording power according to CD-R/RW
Media in recording start step.
ROPC Running OPC. The purpose is to continuously adjust the writing power to the optimum power that is
required
When the optimum power may change because of changed conditions of disc and change in
operating temperature,
Jitter The 1ø value of the time variation between leading and trailing edges of a specific (Mark) pit or land
as measured by Time Interval Analysis
Deviation The difference between a fixed value of Pit length and Land length
TOC Table Of Contents : in the Lead-in Area the subcode Q-channel contains information about the Track
on the disc
Packet Writing A method of writing data on a CD in small increments.
Two kinds of packets can be written : Fixed-length and Variable-length
Write Strategy The shape of the HF write signal used to modulate the power of the laser. The Write Strategy must
be used for recordings necessary for disc measurements
Information Area Wobble, ATIP, Disc Identification, Write Power, Speed Range OPC Parameters, etc are recorded in
the Information area of CD-RW Disc
Finalization The action in which (partially) unrecorded or logically erased tracks are finished and the Lead-in
and/or Lead-out areas are recorded or overwritten with the appropriate TOC subcode
Logical Erase A method to remove information from a disc area by overwriting it with an EFM signal containing
mode 0 subco A logically erased area is equivalent to an unrecorded
Physical Erase The action in which previously recorded information is erased by overwriting with a CW laser output.
After a Physical Erase action ,the erased area on the CD-RW disc is in the unrecorded state again.
Session An area on the disc consisting of a Lead-in area ,a Program area,a Lead-out area.
Multi session A session that contains or can contain more than one session composed Lead-in and Lead-out
GLOSSARY
- a spatial period of 54 -64µm
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