Philips Compact Disc Recordable manual Temperature Laser beam Required temperature to burn a pit

Thermo-BalancedWriting

Fig. 1,Thermo- BalancedWriting:

Typical Heat Profile during CD-R write phase.Goal ofTBW is to ensure a correctly balanced heat profile during this phase.

temperature

laser beam

required temperature to burn a pit

diameter of pit is smaller than diameter of laser spot

laser spot

Equally of course, if the pits come out too small or too light, then other reading errors can occur. If a CD-R drive has no way of controlling the burn process, to adapt itself to the nature of the media, then the use of such sub-standard discs is far more likely to result in defective recordings and, more importantly, severe End-user disappointment.

Fig. 2,Thermo- BalancedWriting: Pit & Land Cross section. A build up ofThermal “cross-talk” during

successive “burns” creates pits with variable dimensions, and the possibility of

errors when data is read back.