公开(公告)号：JPH10320943A

公开(公告)日：1998-12-04

申请号：JP6294498

申请日：1998-03-13

Applicant: PHASE METRICS INC

Inventor： ALEX MORALEU ,  BLASSTIMIL SEJINA ,  MICHAEL INVER ,  KEN WOMACK ,  ROBIN SWEYN

IPC: G11B21/10

Abstract: PROBLEM TO BE SOLVED: To facilitate writing into a wide clock track by a method wherein writing or stamping is applied to the reference surface of a magnetic memory disc while the magnetic memory disc is fixed to a head disc which is approximately enclosed and a clock track is read and a servo track is written through the window of a head disc assembly. SOLUTION: A reference head 122 writes a reference track on a disc 112 by using an instruction generated by a reference and pattern generating board 134. Then a clock head 124 writes a clock track by using the output of the reference head 122 and the transition timing of the clock track is matched and transitions of different clock parts are properly properly arranged. The clock writing position is monitored by a laser position transducer which has a laser 144 using an interferometer construction and a clock track with a width of several hundreds μm can be generated.