US 11,942,122 B1
Determining absolute position on HDD spiral patterns using dual TDMR readers
Gary W. Calfee, Santa Clara, CA (US); Gabor Szita, Mountain View, CA (US); and Jiangang Liang, Saratoga, CA (US)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Electronic Devices & Storage Corporation, Tokyo (JP)
Filed by Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Electronic Devices & Storage Corporation, Tokyo (JP)
Filed on Jan. 17, 2023, as Appl. No. 18/155,633.
Int. Cl. G11B 5/596 (2006.01); G01D 5/248 (2006.01); G11B 5/56 (2006.01)
CPC G11B 5/59666 (2013.01) [G01D 5/248 (2013.01); G11B 5/59661 (2013.01); G11B 5/56 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of determining radial position of a magnetic head that includes a first read sensor and a second read sensor, the method comprising:
with the first read sensor, detecting a servo spiral formed on a disk;
with the second read sensor, detecting the servo spiral;
measuring a time interval between when the servo spiral is detected by the first read sensor and when the servo spiral is detected by the second read sensor; and
based on the time interval, determining a radial position of the magnetic head relative to the disk.