Optical information recording apparatus.

摘要

The apparatus optically records digital information on a recording medium, for example, a disc, a tape and so on. The area of an optical spot cannot be made smaller than a minimum area determined by a numerical aperture of an objective lens and the wave length of a reproducing beam. Consequently, this causes a problem that the code of digital signals often fails to be discriminated in reproducing short pits and/or short pit-intervals which are recorded on the recording medium. The apparatus detects a phase difference between each edge of an input digital signal and each corresponding edge of a digital signal reproduced from the recording medium. The edges of a next input digital signal of the same code construction as that of the first input signal are corrected by a correction amount according to the above phase difference, and such operations are repeated whenever input digital signals are inputted. Consequently the apparatus can decrease errors of code discrimination to minimum and achieve high edge correction. Furthermore, since the input digital signal is delayed by a time interval between the recording by the recording head and the reproducing by the reproducing head, edge correction can be achieved with high precision.