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5. Writing Process of CD-R Disc
a b c d e f g
a
b
c
d
e
f
g
Incident
Laser
Power
(Read)
(Read)
(Write)
Laser Spot
Position
(Time)
a b c d e f g
Laser Spot
Position
(Time)
Laser
Spot
Recorded
Mark
Reflected
Light
Signal
Reflected
Light
Signal
Below "ORP"– Mark Too Short
At Optimum Record Power ("ORP")
Above "ORP" – Mark Too Long
Time
6. Writing process of CD-RW Disc
Write Power
Erase Power
Read Power
Groove
Crystal
Amorphous
Amorphous
Recorded state
(lower reflectivity)
Melting/
quenching
Heating/
gradual cooling
Crystal phase
Erased state
(higher reflectivity)