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公开(公告)号：US4707631A
公开(公告)日：1987-11-17
申请号：US886457
申请日：1986-07-17
CPC分类号： H03H9/1455 , H03H3/08 , H03H9/02559
摘要： A surface acoustic wave (SAW) diffraction-effect or interference-effect device with a highly isotropic substrate having a high coupling coefficient and low attenuation losses. The use of X-propagating rotated-Y-cut lithium niobate as the SAW substrate, with the Y rotation angle selected at 121 degrees, provides a practically isotropic material, with a high coupling coefficient and relatively low attenuation losses.
摘要翻译： 具有高耦合系数和低衰减损耗的高均相衬底的表面声波（SAW）衍射效应或干涉效应器件。 使用X传播的旋转Y型切割铌酸锂作为SAW基片，其中Y旋转角度选择为121度，提供实际上各向同性的材料，具有高耦合系数和相对低的衰减损耗。
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公开(公告)号：US4513261A
公开(公告)日：1985-04-23
申请号：US493917
申请日：1983-05-12
CPC分类号： H03H9/6426 , H03H9/027 , H03H9/0285 , H03H9/14552
摘要： An acoustic wave filter device with low loss and low passband ripple characteristics. The filter comprises three bidirectional electroacoustical transducers disposed along a common axis on the surface of a substrate of piezoelectric material. The two outer transducers of the three function as input transducers and the center transducer functions as an output transducer. One of the input transducers is of the antisymmetric type and has a transfer characteristic that differs in phase angle by ninety degrees with respect to the other input transducer, which is of the symmetric type. This ninety-degree difference applies at all frequencies, so that any energy reflected from the output transducer and again reflected by an input transducer will be subject to a phase shift of 180 degrees in the case of energy reflected from the antisymmetric input transducer, and no phase shift in the case of the symmetric input transducer. Accordingly, these triple-transit echoes will cancel at the output transducer, for all frequencies. For the primary energy propagation from the input transducers to the output transducer, a ninety-degree phase shifter in one input circuit ensures that the signals from the two input transducers are in phase when they reach the output transducer.
摘要翻译： 具有低损耗和低通带纹波特性的声波滤波器件。 该滤波器包括沿着压电材料的基板的表面上的公共轴设置的三个双向电声换能器。 三个功能的两个外部传感器作为输入传感器，中心传感器用作输出传感器。 输入换能器中的一个具有反对称型，并且具有相对于对称型的另一输入换能器将相位角相差九十度的传递特性。 这个九十度的差异适用于所有的频率，所以从反输入传感器反射的能量的情况下，从输出传感器反射并再次被输入传感器反射的任何能量将经历180度的相移，而没有 在对称输入传感器的情况下的相移。 因此，对于所有频率，这些三重传输回波将在输出传感器处消除。 对于从输入传感器到输出传感器的一次能量传播，一个输入电路中的九十度移相器确保来自两个输入传感器的信号在到达输出传感器时处于同相状态。
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公开(公告)号：US4249146A
公开(公告)日：1981-02-03
申请号：US14393
申请日：1979-02-23
CPC分类号： H03H9/25
摘要： A surface acoustic resonator including an interdigital transducer configured to generate acoustic waves at at least one harmonic frequency, and a pair of reflection gratings capable of essentially total reflection of the acoustic waves in both fundamental and harmonic modes of operation. One-port and two-port resonators are disclosed, capable of operation at fundamental and harmonic frequencies, to provide a higher frequency of operation without correspondingly higher resolution requirements for manufacturing processes. For single-mode operation at higher frequencies, the interdigital transducer and reflection gratings have different fundamental frequencies, and utilize harmonics of different order but the same actual frequency, such that the resonator functions at a single frequency, which may be, for example, the third harmonic with respect to the transducer fundamental frequency, and the second harmonic with respect to the reflection grating-fundamental frequency.
摘要翻译： 一种表面声谐振器，包括配置成产生至少一个谐波频率的声波的叉指换能器，以及能够在基本和谐波运行模式中基本上完全反射声波的反射光栅。 公开了能够在基波和谐波频率下操作的单端口和双端口谐振器，以提供更高的操作频率，而无需相应的制造过程更高的分辨率要求。 对于在较高频率下的单模操作，叉指式换能器和反射光栅具有不同的基频，并且利用不同阶数但相同的实际频率的谐波，使得谐振器在单个频率下起作用，其可以是例如 相对于换能器基频的三次谐波，相对于反射光栅基频的二次谐波。
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公开(公告)号：US4499393A
公开(公告)日：1985-02-12
申请号：US580575
申请日：1984-02-15
IPC分类号： G01H3/04 , G01H3/08 , G01R23/02 , G01R23/16 , G01R23/17 , H03H9/145 , H03H9/64 , H03H9/25 , H01L41/08
CPC分类号： G01R23/17 , H03H9/1455
摘要： A surface acoustic wave (SAW) device configured to operate as a spectrum analyzer, and having an array of input transducers disposed on a substrate in such positions as to produce a focused beam of acoustic energy at a focal arc, each position on the arc being representative of an input signal frequency. Output transducers produce electrical signals corresponding to the energy received at successive segments of the focal arc. The disclosed device includes various combinations of input transducer array improvements, some of which are to provide amplitude weighting of the input array, including aperture width weighting, capacitive weighting, resistive weighting, series-parallel weighting, and source withdrawal weighting. Another improvement in input array configuration eliminates close or overlapping electrodes of opposite polarities and thereby reduces parasitic capacitance and acoustic radiation between electrode elements. The use of curved input transducer fingers improves operation of the transducers as point sources. Other important improvements include the use of acoustic transducers before to transmit the focused output energy from the focal line to conventional output transducers, thereby improving frequency resolution, and the use of electromagnetic waveguides to transmit energy from output transducers located on the focal line.
摘要翻译： 一种表面声波（SAW）装置，被配置为作为频谱分析仪进行操作，并且具有设置在基板上的输入换能器阵列，以便在聚焦弧处产生聚焦的能量束的位置，弧上的每个位置 代表输入信号频率。 输出换能器产生对应于在焦弧的连续段处接收的能量的电信号。 所公开的设备包括输入换能器阵列改进的各种组合，其中一些是提供输入阵列的幅度加权，包括孔径宽度加权，电容加权，电阻加权，串联并行加权和源提取加权。 输入阵列配置的另一改进消除了相反极性的紧密或重叠的电极，从而减小电极元件之间的寄生电容和声辐射。 使用弯曲的输入传感器手指改善了作为点源的换能器的操作。 其他重要的改进包括在将聚焦输出能量从焦线传输到常规输出换能器之前使用声换能器，从而提高频率分辨率，以及使用电磁波导从位于焦线上的输出换能器传输能量。
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公开(公告)号：US4290033A
公开(公告)日：1981-09-15
申请号：US45159
申请日：1979-06-04
CPC分类号： H03H9/027 , H03H9/02236 , H03H9/02653 , H03H9/02716 , H03H9/02795
摘要： Energy trapping elements for use with shallow bulk acoustic wave devices of various kinds, to minimize the insertion loses in such devices due to spreading of electroacoustic energy into the crystal substrate upon which the devices are constructed. Electroacoustic energy propagated in a substrate is trapped close to the surface of the substrate by means of trapping elements comprising a plurality of strips or grooves disposed on the surface of the substrate in the path of the propagated energy, and oriented approximately perpendicularly to the direction of propagation. The spacing of the elements is such that their stop-band frequency, at which energy will be reflected, is substantially different from the characteristic center frequency of the entire device, in order that the elements will serve a purely trapping function and not a reflecting function.
摘要翻译： 用于各种浅层体声波器件的能量捕获元件，以便由于电声能量扩散到构造器件的晶体衬底中而最小化这些器件中的插入损耗。 在衬底中传播的电声能量通过捕获元件捕获，靠近衬底的表面，捕获元件包括在传播能量的路径中设置在衬底表面上的多个条或槽，并且大致垂直于 传播。 元件的间距使得其能量将被反射的阻带频率与整个器件的特征中心频率基本上不同，以便元件将用于纯捕获功能而不是反射功能 。
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公开(公告)号：US4926146A
公开(公告)日：1990-05-15
申请号：US161524
申请日：1988-05-09
IPC分类号： H03H9/02
CPC分类号： H03H9/02976
摘要： A surface acoustic wave (SAW) device for converting multiple parallel signals to a smaller number of serial signals. The device includes a piezoelectric substrate and a surface acoustic wave (SAW) input transducer for propagating periodic surface acoustic waves across the substrate. The parallel signals are input to the device through an array of acoustic charge transport (ACT) input transducers, which convert the signals into packets of electrical charge that are transported across the device with the surface acoustic waves generated at the SAW input transducer. An ACT output transducer converts the charge packets back into electrical signals, but in serial rather than parallel form. The converter of the invention can be usefully combined with a SAW channelizer or spectrum analyzer, to provide serial outputs from the analyzer.
摘要翻译： 一种用于将多个并行信号转换为较少数量的串行信号的表面声波（SAW）装置。 该装置包括压电基片和表面声波（SAW）输入换能器，用于在基片上传播周期性表面声波。 并行信号通过声电荷传输（ACT）输入传感器的阵列输入到器件，其将信号转换成跨过器件传输的电荷分组，并在SAW输入传感器处产生声表面波。 ACT输出传感器将电荷数据包转换成电信号，但是以串行方式而不是并行形式转换。 本发明的转换器可以有效地与SAW通道器或频谱分析仪组合，以提供来自分析仪的串行输出。
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公开(公告)号：US4349794A
公开(公告)日：1982-09-14
申请号：US954149
申请日：1978-10-24
申请人： Reynold S. Kagiwada , Kuo-Hsiung Yen , Ke-Li Wang , Kei F. Lau , Donald L. Lochhead , James A. Leaverton
发明人： Reynold S. Kagiwada , Kuo-Hsiung Yen , Ke-Li Wang , Kei F. Lau , Donald L. Lochhead , James A. Leaverton
CPC分类号： H03H9/02795 , H03H9/02236 , H03H9/02653 , H03H9/027 , H03H9/02716
摘要： Acoustic wave devices employing shallow bulk acoustic waves rather than surface acoustic waves, to provide higher frequencies of operation and other significant advantages, such as less susceptibility to aging and less sensitivity to surface contamination. In each embodiment of the invention, a transmitting transducer and a receiving transducer are oriented on the surface of an anisotropic piezoelectric crystal to achieve substantial coupling of shallow bulk acoustic waves and essentially zero coupling of surface acoustic waves. In one embodiment of the invention, various types of grating filters utilize shallow bulk acoustic waves, and a set of parallel mechanical or electrical discontinuities at or near the surface of the crystal provide reflection of acoustic energy at a frequency determined by the spacing of the discontinuities. Uniformly spaced gratings provide bandpass filter operation, and gratings with graduated spacings provide for frequency compression or expansion. In another embodiment of the invention, variations in device characteristics due to temperature changes are compensated for by directing the shallow bulk waves through materials having favorable or opposite temperature characteristics compared with those of the material into which the waves are originally launched. In other embodiments of the invention, a shallow bulk acoustic wave includes a multistrip coupler, for transferring electroacoustic energy from one propagation path to another, for use in bandpass filters, delay lines or unidirectional transducers.
摘要翻译： 使用浅体积声波而不是表面声波的声波装置，以提供更高的操作频率和其他显着的优点，例如对老化的敏感性较低和对表面污染的敏感性较小。 在本发明的每个实施例中，发射换能器和接收换能器定向在各向异性压电晶体的表面上，以实现浅体积声波和表面声波的基本零耦合的实质耦合。 在本发明的一个实施例中，各种类型的光栅滤波器利用浅体积声波，并且在晶体表面处或附近的一组平行的机械或电气不连续性以由不连续部分的间隔确定的频率提供声能的反射 。 均匀间隔的光栅提供带通滤波器操作，具有刻度间距的光栅可用于频率压缩或扩展。 在本发明的另一个实施例中，由于温度变化引起的器件特性的变化是通过将浅体积波导入具有有利或相反温度特性的材料来补偿的，与材料相比，波浪最初被发射的材料。 在本发明的其他实施例中，浅体积声波包括用于将电声能从一个传播路径转移到另一传播路径的多带耦合器，用于带通滤波器，延迟线或单向换能器。
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公开(公告)号：US4012120A
公开(公告)日：1977-03-15
申请号：US577266
申请日：1975-05-14
申请人： Reynold S. Kagiwada , David B. Hall
发明人： Reynold S. Kagiwada , David B. Hall
摘要： An acousto-optic device suitable as a correlator, convolution integrator or Fourier transform device. The device comprises a piezoelectric substrate or crystal such as lithium niobate. The substrate is covered by a thin, outer layer having higher index of refraction than the substrate and a thickness on the order of 50 micrometers. Two acoustic transducers such as interdigital transducers are disposed on opposite ends of the crystal to launch two acoustic surface waves in opposite directions. A laser beam is guided through the outer layer and is coupled with the two acoustic waves to generate either a correlation function, a Fourier transform or a convolution integral depending on the signals impressed thereon.
摘要翻译： 适合作为相关器，卷积积分器或傅立叶变换装置的声光装置。 该器件包括压电基片或诸如铌酸锂的晶体。 衬底被薄的外层覆盖，其具有比衬底更高的折射率，并且厚度为50微米。 两个声换能器如叉指换能器设置在晶体的相对端上，以相反的方向发射两个声表面波。 激光束被引导穿过外层并且与两个声波耦合，以产生相关函数，傅立叶变换或卷积积分，其取决于其上施加的信号。
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