1. Field of the Invention
This invention relates to a recorder and a method for determining a recording signal of the recorder.
2. Description of Related Art
Optical recorders for recording data onto recordable optical discs are widely used. Recordable discs, such as DVD-R/RW, DVD+R/RW, and CD-R/RW, are popular optical storage media in the consumer electronics market.
A typical recorder uses a laser beam to record the data onto the disc. The laser beam is controlled by a recording signal of the recorder. The power level of the recording signal determines the optical power of the laser beam. If the optical power of the laser beam is not strong enough, the data recorded on the disc by the laser beam may not be readable.
Generally, the recording signal of the recorder to record the data onto the disc are predetermined by a disc manufacturer or the recorder manufacturer. For example, a recorder identifies a disc loaded in the recorder by reading a media ID (MID) embedded in the disc; thus optimized parameters for determining the recording signal stored in the recorder is selected according to the MID.
However, the optimized recording parameters for the recording signal may not be appropriate to record different discs; even if the discs have a same MID. For example, a first batch of the discs may have data written on them soon after being manufactured, while a second batch of the discs may have data written on them after an extended period of time and may have being subjected to different environmental conditions. The recording properties of these two batches of discs may change due to such conditions as temperature and humidity.
Therefore, a method and an apparatus for determining the recording signal are desired.