scan slicer module 20 determines the sectioning line according to the orientation u03b8 and to the maximum amplitude position p max in step 514 amplitude values along the sectioning line are analyzed to find half amplitude point a half and half amplitude b half corresponding to each indication side p a and p b respectively in step 516 a scan exhibition at p a and p b in fig3 are analyzed to obtain time of flights t a and t b shown in fig3 respectively in step 518 the indication depth d is calculated using eq 2 shown below in step 520 calculated length l and depth d not shown are displayed by display unit 28 d a max t b u2212 t a calibrationfactor eq 2 wherein d is the size of depth or thickness of the found indicator a max the maximum amplitude along the sectioning line t a and t b are the time of flights at half amplitude before and after a max respectively on the sectioning line and calibration factor is the calibrated factor obtained from eq 1 corresponding to the calibration process shown in fig4 although the present invention has been described in relation to particular exemplary embodiments thereof many other variations and modifications and other uses will become apparent to those skilled in the art it is preferred therefore that the present invention not be limited by the specific disclosure for example the scope of the present disclosure may be applied to a wide range of ultrasonic systems such as but not limited to ultrasonic ut single element multi element and array probes it should.