An organism observation device comprises an ultrasonic wave generating unit for outputting an ultrasonic wave toward a predetermined region inside the subject, an illuminating light generating unit for projecting illuminating light onto the predetermined region where the ultrasonic wave is projected, a phase component detecting unit for detecting the first to N-th phase components of the returning light of the illuminating light projected onto the predetermined region corresponding to respective first to N-th timings by time resolving the returning light from the first timing to N-th timing, and computing unit for subtracting the sum of the first to (N-1)-th phase components from the N-th phase component using the phase components detected by the phase component detecting unit.
ORGANISM OBSERVATION DEVICE AND ORGANISM TOMOGRAM CREATING METHOD