| 摘要 |
PURPOSE:To detect recording error accurately and to simplify the constitution of optical system, by separating a recording beam and a monitor beam with pure electric methods. CONSTITUTION:A beam 21 in luminance modulation according to a recording signal 27 is irradiated on an optical type recording medium 26 and the information construction is recorded. When it is detected whether the signal 27 is correctly recorded or not, a beam 30 in luminance modulation with a monitor modulation signal 37 is irradiated on the medium 26 so that the beam 30 can be emitted at the distinguishing period of the beam 21 in a sufficiently shorter period than the period of the signal 27 and it is positioned immediately after the beam 21. The reflected beam from the medium 26 is detected 35 to pick up a playback signal, from which the modulation component by the beam 21 through the use of the signal 37 is eliminated at 40. An information signal representing the information construction recorded on the medium 26 is picked up 41, this information signal and the recording signal are compared 42 to detect recording error. |
