PROBLEM TO BE SOLVED: To attain accurate discrimination of tissue properties and to improve the reliability of an observation result.SOLUTION: An ultrasonic observation apparatus computes a frequency spectrum by analyzing the frequency of ultrasonic waves received at a predetermined receiving depth, stores a predetermined frequency value as an upper limit value of a frequency band at the predetermined receiving depth for each receiving depth, performs setting for limiting the frequency band of the frequency spectrum computed by a frequency analysis part based on the upper limit value of the frequency band, stores a reference spectrum at the predetermined receiving depth obtained based on the frequency of ultrasonic waves received from a reference reflecting body, for each receiving depth, corrects the frequency spectrum computed by the frequency analysis part based on the reference spectrum stored by a reference spectrum information storage part, to compute a corrected frequency spectrum, and performs approximate processing to the corrected frequency spectrum in a predetermined frequency band to extract a feature quantity that shows the tissue properties of a specimen from the result of approximate processing.COPYRIGHT: (C)2013,JPO&INPIT【課題】組織性状を精度よく鑑別することを可能にするとともに、観測結果の信頼性を向上させる。【解決手段】所定の受信深度で受信した超音波の周波数を解析することによって周波数スペクトルを算出し、所定の受信深度における周波数帯域の上限値として所定の周波数値を受信深度ごとに記憶し、周波数帯域の上限値に基づいて、周波数解析部が算出した周波数スペクトルの周波数帯域を制限する設定を行い、基準反射体から受信した超音波の周波数をもとに得られた所定の受信深度における基準スペクトルを受信深度ごとに記憶し、基準スペクトル情報記憶部が記憶する基準スペクトルをもとに周波数解析部が算出した周波数スペクトルを補正することによって補正周波数スペクトルを算出し、所定の周波数帯域における補正周波数スペクトルに対して近似処理を行い、近似処理結果から検体の組織性状を示す特徴量を抽出する。【選択図】図1
