Patent ID: 6827247
Filing Date: 2004-12-07
Classification: B23K,H01L

Abstract:
Apparatus for detecting the oscillation amplitude of an oscillating object, the apparatus comprising:an optical radiation source; a detector oriented for receiving optical radiation from said optical radiation source, said detector comprising first and second optical radiation sensors adjacent each other and both receiving said optical radiation from said optical radiation source, the detector and the optical radiation source being adapted to be located on opposite sides of the oscillating object from each other, with the oscillating object located between the source and the detector so that when so located, the object blocks a portion of the optical radiation directed toward said detector from the source; and a processor coupled to the detector to receive first and second output signals generated respectively by the first and second sensors and representing the magnitude of optical radiation sensed by the first and second optical radiation sensors, respectively; wherein the processor processes the first and second output signals to obtain an indication of the amplitude of oscillation of the object; wherein said oscillating object is an ultrasonic transducer; and wherein the width of each of the first and second optical radiation sensors is greater than the sum of half the width of the oscillating object and the amplitude of oscillation of the object.