Patent ID: 8442246

Claim:
A hearing aid device comprising: a plurality of microphones configured to convert picked sound to audio signals: an inter-signal phase difference calculation unit configured to calculate a phase difference between a first audio signal converted by a first microphone of the plurality of microphones and a second audio signal by a second microphone of the plurality of microphones; a hand placement determination unit configured to determine whether a state where the phase difference is a first threshold value or less continues for a first time; a directivity sound pickup unit configured to superimpose a sensitivity-frequency characteristic for controlling sensitivity in a sound pickup direction on the first audio signal acquired from the first microphone and the second audio signal acquired from the second microphone to control the frequency characteristics of the audio signals, and to generate an output signal; a nonlinear amplification unit configured to control a signal level of the output signal acquired from the directivity sound pickup unit; and a hearing aid process control unit configured, when the hand placement determination unit determines that the state where the phase difference is the first threshold value or less continues for the first time, to control the directivity sound pickup unit such that at least one of the sensitivity-frequency characteristic and the frequency characteristics of the audio signals becomes nondirective, and to control the nonlinear amplification unit to amplify signal levels of the acquired audio signals.