PROCEDE POUR PRODUIRE ET/OU POUR RECEVOIR DES SIGNAUX ULTRA-SONORES

• Main Author: KLAUS ABEND ET URSULA ORTHEN
• Format: Patent
• Language: French
• Published: 13.08.1982
• Subjects: DEAF-AID SETS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; FOR PERFORMING MECHANICAL WORK IN GENERAL; GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKEACOUSTIC ELECTROMECHANICAL TRANSDUCERS; MEASURING; METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICALVIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY; PERFORMING OPERATIONS; PHYSICS; PUBLIC ADDRESS SYSTEMS; TESTING; TRANSPORTING

In a method for generating and/or for receiving ultrasonic signals by using a piezoelectric crystal, a higher resolution, improved location of faults and detection of the type of fault are achieved by arranging for the crystal to be predeformed continuously during measurement by a DC voltage. At the same time, bipolar pulses can be applied to the quartz crystal, resulting, e.g., in a simplification of the frequency analysis and of the phase shift. A.PROCEDE POUR PRODUIRE ETOU POUR RECEVOIR DES SIGNAUX ULTRA-SONORES EN UTILISANT UN CRISTAL PIEZOELECTRIQUE.B.PROCEDE CARACTERISE EN CE QUE LE CRISTAL 10 EST PRE-DEFORME PAR APPLICATION D'UNE TENSION CONTINUE.C.L'INVENTION S'APPLIQUE NOTAMMENT AU CONTROLE NON DESTRUCTIF DES MATERIAUX.