Apparatus for and method of adding information onto recording medium that enables additional recording

An apparatus for recording first information onto a recording medium, successively to second information that has been already recorded on the recording medium, both the first and second information being divided into a plurality of blocks each having a predetermined length, each of the plurality of blocks including a synchronization signal, the synchronization signal being located at a predetermined position in each of the plurality of blocks, a plurality of pre-pits being pre-formed on the recording medium at intervals of the predetermined length or an integer times the predetermined length, a reference signal being pre-recorded on the recording medium, the reference signal having a predetermined frequency, the apparatus comprising:

• a write clock signal generating device for generating a write clock signal on the basis of the reference signal obtained from the recording medium;
• a pre-pit detecting device for detecting the plurality of pre-pits from the recording medium and outputting a pre-pit signal at a first timing, the first timing being equal to a timing that each of the plurality of pre-pits is detected;
• a synchronization signal generating device for generating the synchronization signal and outputting the synchronization signal at a second timing, the second timing being synchronized with the write clock signal, the second timing being set so as to place the synchronization signal at the predetermined position in each of the plurality of blocks;
• a time relationship detecting device for detecting a time relationship between the pre-pit signal and the synchronization signal;
• a shifting device for shifting a phase of the write clock signal so as to make the detected time relationship equal to a predetermined time relationship;
• and
• a recording device for recording the first information and the synchronization signal onto the recording medium in accordance with the second timing.