Patent ID: 7575551

Claim:
A biological signal monitor device, comprising: an ultrasonic wave transmission/reception unit for transmitting first and second ultrasonic pulses time sequentially into a living body, receiving first and second ultrasonic echo signals from a living tissue, and converting the ultrasonic echo signals into electric signals; a movement amount detection unit for analyzing a phase of the ultrasonic echo signals from the living tissue obtained by the ultrasonic wave transmission/reception unit, wherein analyzing the phase of the ultrasonic echo signals includes detecting an amount of a phase shift between the ultrasonic echo signals, and detecting an amount of movement of the living tissue in accordance with a body motion due to a heartbeat or a vibration, wherein detecting the amount of movement includes converting the amount of the phase shift into a distance; a correction unit for correcting the ultrasonic echo image signals based on the amount of movement of the living tissue detected by the movement amount detection unit in order to perform reverse correction with the amount of movement, thereby removing a variation due to the movement, resulting in reverse corrected ultrasonic echo signals; a generation unit for subjecting the reverse corrected ultrasonic echo signals to averaging and filter processing, thereby generating filter-processed ultrasonic echo signals, wherein a random noise component is reduced from the reverse corrected ultrasonic echo signals; a reverse conversion unit for subjecting the filter-processed ultrasonic echo signals to reverse conversion so as to be put back to a state where an image of the living tissue moves in accordance with a body motion or a vibration; and a display unit for displaying the image based on the reverse converted ultrasonic echo signals.