METHOD, OPTICAL RECORDING APPARATUS USING SUCH METHOD AND OPTICAL RECORDING MEDIUM FOR USE BY THE METHOD AND THE APPARATUS

摘要

A method for setting an optimum value of a write power level for use in an optical recording apparatus for writing information on a recording layer (3) of an optical recording medium (1) by means of a radiation beam (5) is described. The recording layer is able to change between an amorphous and a crystalline state. The apparatus comprises a radiation source (4) for emitting the radiation beam (5) having a controllable value of a write power level (PW) for recording information on the recording medium, a control unit (12) for recording a series of test patterns in a test area on the recording layer, each pattern being recorded with a different value of the write power level, a read unit (90) for reading the patterns and forming corresponding read signal portions, and first means (10, 101, 102) for deriving a value of a read parameter from at least one read signal portion and setting an optimum value (P opt)of the write power level based on the values of this read parameter. According to the invention the apparatus further comprises second means to perform at least one initial step (40) of at least partly amorphizing and subsequently recrystallizing the recording layer. In this way a consistent result for the determined optimum value (Popt) of the write power level (Pw) is obtained.