PROBLEM TO BE SOLVED: To provide a surface characteristic measurement technique which allows the surface characteristic of a material to be accurately evaluated.SOLUTION: With a surface characteristic measurement method, ultrasonic waves are emitted to a measurement object so as to acquire a refection signal from the measurement object, a measurement device calculates the maximum value of a cross correlation function between the reflection signal from the measurement object and a pre-acquired reference reflection signal from a reference material so that a reflection component at the boundary face is calculated by using the maximum value of the cross correlation function, and either an acoustic impedance of the measurement object or an acoustic impedance of the reference object is output as the measurement value according to a result of comparison between the reflection component and the reference reflection signal.SELECTED DRAWING: Figure 6【課題】物質の表面特性を精度良く評価することのできる表面特性測定技術を提供する。【解決手段】表面特性測定方法は、測定対象物に超音波を照射して前記測定対象物からの反射信号を取得し、測定装置にて前記測定対象物からの反射信号と、あらかじめ取得した参照物質からの参照反射信号との相互相関関数の最大値を計算し、前記相互相関関数の最大値を用いて界面での反射成分を計算し、前記反射成分と前記参照反射信号の比較結果に応じて、前記測定対象物の音響インピーダンスと前記参照物質の音響インピーダンスのいずれか一方を測定値として出力する。【選択図】図６
