Servo track writing device and method thereof

A servo track writing method in which each track on a disc medium plane is divided to a plurality of sectors and a format pattern signal containing a servo frame signal is written into each sector, the servo track writing method comprising:

• a clock detecting step for detecting a clock pattern formed on a disc rotated at a constant speed through anon-contact sensor and outputting;
• a clock generating step for generating a clock signal of arbitrary format frequency set up preliminarily based on a clock signal of a predetermined frequency from the non-contact sensor;
• and
• a writing processing step for writing a format pattern signal into the disc medium face according to a synchronous signal of a turn of the disc and the clock signal of the format frequency.

A servo track writing device in which each track on a disc medium plane is divided to a plurality of sectors and a format pattern signal containing a servo frame signal is written into each sector, the servo track writing device comprising:

• non-contact sensors for detecting a clock pattern formed on a disc rotated at a constant speed through non-contact and outputting a clock signal;
• a vibration extraction processing unit for extracting a deflection component synchronous with a rotation from a clock signal of the non-contact sensors so as to correct a clock jitter;
• a clock generating unit for generating a fixed clock signal of an arbitrary format frequency preliminarily set up according to the clock signal from the vibration extraction processing unit;
• a sector correction processing unit which measures an error due to a frequency deflection synchronous with a rotation with respect to a preliminarily determined writing start position for each sector of the disc and corrects a writing start position of a format pattern signal for each sector including a servo frame signal stored in a memory according to the measured error;
• and
• a writing processing unit for reading out a corrected format pattern signal in the memory according to a synchronous signal of a turn of the disc and the clock signal of the format frequency and writing into each track of the disc medium face.

A servo track writing method in which each track on a disc medium plane is divided to a plurality of sectors and a format pattern signal containing a servo frame signal is written into each sector, the servo track writing method comprising:

• a vibration extracting step for detecting a clock pattern formed on a disc rotated at a constant speed through non-contact, extracting a deflection component synchronous with a rotation from an output clock signal of a predetermined frequency and correcting a clock jitter;
• a clock generating step for generating a clock signal of any format frequency preliminarily set up according to a clock signal from the vibration extracting step;
• a sector correcting step for measuring an error due to a frequency deflection synchronous with a rotation with respect to a preliminarily determined writing start position for each sector of the disc and correcting a writing start position of a format pattern signal for each sector including a servo frame signal stored in a memory according to the measured error;
• and
• a writing step for reading out a corrected format pattern signal in the memory according to a synchronous signal of a turn of the disc and the clock signal of the format frequency and writing into each track of the disc medium face.