| 摘要 |
FIELD: physics. ^ SUBSTANCE: apparatus for emitting and/or receiving ultrasound with at least one given frequency, having at least one ultrasonic transducer for converting ultrasound with at least one given frequency into electrical signals and/or for converting electrical signals into ultrasound with at least one given frequency and a holder having at least one ultrasonic channel in which the ultrasonic transducer partially lies and/or through which ultrasound can pass from the ultrasonic transducer to it, and which has at least one non-fibrous surface layer adjoining at least one section of the ultrasonic channel, said surface layer having overall resistance which is less than overall resistance of the inner layer of the holder adjoining this surface layer, wherein the surface layer is made from material whose average density is at least 10% lower than the average density of material of the inner layer. ^ EFFECT: possibility of avoiding undesirable reflection of the used ultrasound. ^ 35 cl, 14 dwg |
