Patent ID: 6789426
Filing Date: 2004-09-14
Classification: G01H,G01K,G01N

Abstract:
A sensor for sensing velocity of ultrasonic waves in fluids in microchannels formed in a microfluidic device comprising:a capacitive micromachined ultrasonic transducer integrated in one wall of the channel, a pulser for applying electrical pulses to said ultrasonic transducer to transmit ultrasonic waves which travel through the fluid in said channel and reflect from the opposite wall of said channel, said transducer adapted to receive ultrasonic waves reflected from the opposite wall and generate an output signal, an analog to digital converter connected to received said output signals and provide a representative digital output, and a processor configured to receive said digital output and determine the time of travel of ultrasonic waves through the fluid and to determine from the time of travel and the distance the ultrasonic waves travel through the fluid the velocity of the ultrasonic waves in the fluid.