ULTRASONIC DOPPLER RHEOMETER

摘要

PURPOSE:To provide an ultrasonic Doppler rheometer which allows the obtaining of the best sensitivity at all possible depths to be examined. CONSTITUTION:A frequency control section 32 and a variable frequency oscillating section 33 are combined to change a phase detection reference signal 41 according to a timing signal from a timing generating section 31. A phase detection is performed with a phase shifter 5, a multiplier 6 and a low pass filter using the phase detection reference signal 41 as reference signal thereby enabling the obtaining of the best sensitivity at all depths to be examined.