摘要 |
A record system and method for recording and reproducing information relative to record cards is provided wherein the information is in the form of optically scannable parallel tracks containing recordings therein which are defined by variations in the surface topography of the record tracks. A narrow beam of radiation such as that generated by a laser or an electron beam gun is modulated with information such as a video picture signal or digital information and is caused to scan the surface of a record card to generate either a variable topography represented by variations in the widths and/or depths of the narrow recording area of a record track caused by variations in the intensity of the beam of radiation as the beam is deflected to scan the recording track or the card is automatically moved to effect scanning by the beam. The beam may be operable to vaporize or otherwise variably erode and cause a groove or a series of cavities to be formed along the record track wherein the shape and/or depth of the cavities or separations therein represent electro-optically scannable information such as full-frame video picture signals, digital information and the like. In another form, the card may be coated with an erodable material which is vaporized or otherwise eroded to effect information recordings therein.
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