Patent ID: 8605492

Claim:
A memory device, comprising: a recording medium to store a signal; a probe to write a plurality of the signal in the recording medium in a first direction; a first driving portion to vibratory drive the probe or the recording medium in the first direction; a detecting unit which, before a writing operation, when the first driving portion changes a frequency to vibratory drive the probe or the recording medium in the first direction, detects a change in an amplitude of a resonance drive, and detects the frequency at which the amplitude becomes maximum as a resonance frequency; and a calculating unit which, before the writing operation, calculates a timing when the probe writes a plurality of the signals into the recording medium using the resonance frequency; wherein, at the time of writing, the first driving portion vibratory drives the probe or the recording medium in the first direction at the resonance frequency, and the probe writes a plurality of the signals into the recording medium at the timing.