The present invention relates to a system for recording and reproducing multiplex information. More particularly, the invention relates to a system for recording and reproducing multiplexed multichannel signals such as audio information in addition to video signals.
Video disks serving as information storage media have recorded thereon video signals and different information signals such as audio information signals. The video signals are frequency modulated. The audio signals are two-channel signals to allow for a stereophonic or bilingual program mode. The signals in each channel are recorded on the video disk by frequency modulating two independent audio carriers, together with the frequency-modulated video signals.
There is a demand for the multiplexing of other two-channel information, for example, in addition to the normal two-channel audio information. For reasons described later, there is no space available within the frequency spectrum recorded on a video disk for recording two additional channels. For multiplexing four-channel audio signals, furthermore, compatibility should be taken into account with existing recording and reproducing systems.
It is thus an object of the present invention to provide a multiplex information recording and reproducing method with which other recorded video information is not adversely affected, and which is compatible with existing recording and reproducing systems.
Another object of the present invention is to provide such a multiplex information recording and reproducing system having good reproducing characteristics.