Patent ID: 7969682
Filing Date: 2011-06-28
Classification: G11B

Abstract:
1. A head control device that controls, by thermal expansion caused by a heater, a position of a head that faces a storage medium and reads signals of data recorded on the storage medium, the head control device comprising: a control unit that increases heater power of the heater by a predetermined range; an obtaining unit that obtains a sample of an index value of a signal level read from the storage medium at each heater power controlled by the control unit; a function determining unit that determines a determining function for determining current heater power based on samples obtained by the obtaining unit; a calculating unit that calculates a comparative value corresponding to the current heater power based on the determining function; and a maximum-power determining unit that determines whether the current heater power is maximum power by comparing the comparative value and the index value of the signal level corresponding to the current heater power, wherein the function determining unit includes