METHOD FOR MANUFACTURING MAGNETIC TAPE, SYSTEM FOR MANUFACTURING MAGNETIC TAPE HAVING OPTICALLY DETECTABLE SERVO TRACK, AND ADAPTER BOARD CAPABLE OF INTEGRATING WITH SYSTEM FOR MANUFACTURING MAGNETIC TAPE AND MAGNETIC TAPE HAVING SERVO TRACK ON IT

PROBLEM TO BE SOLVED: To desirously format a recording tape by inscribing plural servo tracks on non-recording surface of a magnetic tape using a laser beam and marking the servo track. SOLUTION: The collimated beam 40 having the interference property of a large power generated by a laser 20 is divided into plural beams 52 by a diffraction optical grating 48. Each of these plural beams has substantially equal power and respectively diverges from the optical path through which the beam 40 is moved. A lens 50 is operated so as to focus individual beams 54 constituting a beam pattern 42 so that respective beams 54 are focused on the surface of a magnetic tape 32. And the array of marks is simultaneously generated by many beams 42. Plural continuous tracks inscribed on the surface of the magnetic tape 32 are included in the servo track formed by the array of the beams 42 by continuously operating the laser 20.