| 摘要 |
PURPOSE:To reproduce separately an image signal and a digital signal with a head having azimuth angles different from each other by recording shallowly a digital signal modulated by the heat having a different azimuth angle on a track recorded with an image signal. CONSTITUTION:The deepness of the recording layer of an image signal is 0.25-0.3 times the recording wavelength, and the signal is recorded up to the depth of 0.3-0.8mum in a domestic VTR. Since the thickness of a magnetic layer 27 of a magnetic tape is 2-4mum, an unrecorded layer 27c is present. As the recording and reproduction of a digital signal do not necessitate so high S/N as the recording and reproduction of an analog signal, a digital signal of a wide band is recorded on the shallow part of a recording layer 27b recorded with an image signal to form a digital signal recording layer 27a. When a digital signal is reproduced with 15dB S/N, the code error rat is a value of 10<-5> which approaches the practical value. Accordingly, 20-30dB S/N including an allowance can be satisfactorily secured. |
