公开(公告)号：US3961291A

公开(公告)日：1976-06-01

申请号：US528176

申请日：1974-11-29

Applicant: Harper John Whitehouse ,  Tibor G. Horwath

Inventor： Harper John Whitehouse ,  Tibor G. Horwath

IPC: G01H3/12 ,  H04B11/00 ,  H04B13/00 ,  H03H9/00

CPC classification number: G01H3/125 ,  H04B11/00

Abstract: Apparatus useful for mapping fields in the range of infrasonic to ultraso, comprising a distributed electrostatic transducer, functioning as a strip transmission line, which includes a flat, substantially rectangular, metal plate, one surface of which is rough, the plate having a length generally in the range of 10 to 100 wavelengths of the frequency at which the mapping is to be done. A rectangular strip of dielectric foil is disposed under tension on the rough surface of the metal plate so that the foil touches only the most protruding parts of the surface. A long, narrow, rectangular, metallic strip is disposed on and attached to the dielectric foil, the strip being exposed to, and therefore defining, an acoustic pressure field.A duplexer is electrically connected to the metallic strip and to the flat plate, and is connectable to a source of input signals, and has output terminals at which the output signal may be measured. The result being that, when an electromagnetic delta function is applied at the input to the duplexer, electromagnetic waves travel along the strip transmission line, the duplexer having the function of separating the returning signal reaching the output terminals of the duplexer from the outgoing signal which is interrogating the line. The returning signal contains two groups of frequencies: (1) low-frequency components identical to those present in the acoustic pressure field, and (2) high-frequency components containing wave vectors, also present in the acoustic pressure field, the two components being readily separable, and hence the pressure field may be reconstructed.

Abstract translation: 用于映射超声波范围内的场的装置，包括用作带状传输线的分布式静电传感器，其包括平坦的，基本矩形的金属板，其一个表面粗糙，该板的长度一般 在要进行映射的频率的10到100个波长的范围内。 电介质箔的矩形条被布置在金属板的粗糙表面上，使得箔仅接触表面的最突出部分。 一个长而窄的矩形金属条被设置在电介质箔上并附着到电介质箔上，该条暴露于声压场并由此限定声压场。