A New Ultra-Thin Acoustic Impedance Transformer

Abstract

The invention belongs to the technical field of the acoustic field, and discloses a novel ultra-thin acoustic wave impedance converter. It is characterized in that it includes one or more impedance transformation units. The impedance transformation unit is composed of a frame, a multi-layer prestressed film or a multi-layer prestressed string net, and a multi-layer acoustic material. There are upper and lower transparent cavities inside the frame, and prestressed films or string nets and acoustic materials are alternately placed inside the cavities, that is, starting from one end of the cavity, a layer of prestressed films or string nets, a layer of acoustic materials, A prestressed membrane or string mesh, a layer of acoustic material, circulates until the cavities are filled. The cavity can be designed into different shapes, including variable cross-section and constant cross-section. Among them, each layer of prestressed film or string net requires prestress before being placed inside the cavity, and the magnitude of the prestress is determined by the expected impedance value of this layer of film or string net. The invention can realize the rapid change of impedance from low to high or from high to low, and realize ultra-thin design.

Description

technical field [0001] The invention belongs to the technical field of acoustics and relates to a novel ultra-thin acoustic wave impedance converter. Background technique [0002] In recent years, the ultra-thin design of various products has become popular all over the world, including ultra-thin mobile phones, ultra-thin TV sets, ultra-thin computers, and ultra-thin, lightweight vibration and noise reduction devices for military and civilian use. In order to meet this demand, domestic and foreign scholars and engineers and technicians have carried out a lot of work, one of the bottlenecks is the ultra-thin design of the acoustic wave impedance transformer. For example, a loudspeaker is a kind of acoustic impedance converter, and its sound quality depends on the size of the end face of the loudspeaker. For a traditional speaker, the larger the diameter of the end face, the greater the thickness of the speaker. At present, in order to realize the ultra-thin design of the a...

AI Technical Summary

Problems solved by technology

Among them, by improving the structural layout to achieve the purpose of reducing the thickness of the acoustic impedance transformer, the development space is extremely limited; and the use of piezoelectric ceramic sheets and flat diaphragms can indeed greatly reduce the thickness of the acoustic impedance transformer, but due to Due to the limitations of their materials or design principles, their low-frequency characteristics are particularly insufficient

At present, under the existing technical conditions, designers can only find a balance point between the performance of the acoustic impedance transformer and the required thickness

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