76 results about "Acoustic medium" patented technology

An apparatus and method for transmitting data and power through a metal barrier using ultrasonic waves, having ultrasonic transmission channels through the barrier formed by coupling ultrasonic transducers on opposite sides of the barrier. A power transmitter sends power over a channel and forward and reverse data transmitters send forward and reverse data signals by orthogonal frequency-division multiplexing OFDM over a separate channel. The data signals are made up of plural sub-carriers at plural different sub-carrier frequencies with none of the sub-carriers of the forward transmission signal being at a power harmonic frequency.

The invention discloses a method and a device for measuring the speed and frequency of ultrasonic traveling wave in a liquid. The method comprises the following steps that a monochromatic parallel light beam is vertical to an ultrasonic transmission direction and radiates a dynamic ultrasonic grating that the ultrasonic wave forms in the liquid; the dynamic ultrasonic grating penetrates through a lens and the diffraction spectrum of a traveling wave ultrasonic phase grating is formed; the spectrum is processed and imaged through an amplitude filter and an imaging lens, and a spectrum image of the ultrasonic traveling wave grating is obtained; the spacing of two adjacent spectral lines on the spectrum image is measured, and the wavelength of the ultrasonic wave in the liquid is calculated; the change of an electrical signal after the previous level of spectrum and zero level spectrum of the spectrum image are mixed is detected or recorded, and the frequency of the ultrasonic wave is worked out; the speed of the ultrasonic wave in the liquid is worked out through the wavelength and the frequency. The device for realizing the method comprises a light source, a transparent sink, a lens I, the amplitude filter, the imaging lens and the measuring device which are sequentially connected, and a sound-absorbing medium and the ultrasonic transducer are arranged in the transparent sink and are respectively arranged on both sides.

An acoustic matching structure is used to increase the power radiated from a transducing element with a higher impedance into a surrounding acoustic medium with a lower acoustic impedance. The acoustic matching structure consists of a thin, substantially planar cavity bounded by a two end walls and a side wall. The end walls of the cavity are formed by a blocking plate wall and a transducing element wall separated by a short distance (less than one quarter of the wavelength of acoustic waves in the surrounding medium at the operating frequency). The end walls and side wall bound a cavity with diameter approximately equal to half of the wavelength of acoustic waves in the surrounding medium. In operation, a transducing element generates acoustic oscillations in the fluid in the cavity. The transducing element may be an actuator which generates motion of an end wall in a direction perpendicular to the plane of the cavity to excite acoustic oscillations in the fluid in the cavity, and the cavity geometry and resonant amplification increase the amplitude of the resulting pressure oscillation. The cavity side wall or end walls contain at least one aperture positioned away from the center of the cavity to allow pressure waves to propagate into the surrounding acoustic medium.

The invention relates to a method for processing seismic exploration data in the process of controlling full acoustic wave equation inversion. The method comprises the following steps: acquiring seismic data of a theoretical model to obtain a depth-domain bulk modulus and density initial model; simulating a seismic wave field in an acoustic medium by a pseudo-spectral method; calculating the difference of analog data of the theoretical model and the initial model; giving that delta is equal to 1.0 e-6; calculating error energy E; when E is less than or equal to delta, stopping inversion and outputting the inversion result; if E is more than delta, continuing the following steps; calculating residual error data; calculating the conjugated modification quantity of the bulk modulus and density model; calculating the modified step length to obtain the gradient; modifying the initial model; using the modified model data as a new initial model; carrying out automatic control on the inversion process to make the acoustic wave equation inversion stable, rapid and convergent and improve the inversion convergence speed by nearly five times than a routine method.

The present invention provides a viscous-acoustic undulating surface forward modeling system and method based on a viscous-acoustic quasi-differential equation, belonging to the field of oil exploration. The method comprises the following steps of: performing irregular mesh generation of speed and quality factors, mapping the speed and quality factors in a mesh coordinate system, mapping a traditional first-order viscous-acoustic-stress equation to a curved mesh coordinate system, and applying the first-order viscous-acoustic-stress equation in the curved mesh coordinate system to deduce a second-order viscous-acoustic quasi-differential equation without memory variables in the same coordinate system. The new viscous-acoustic equation can better control the amplitude loss and phase dispersion caused by the viscous-acoustic medium to more accurately simulate the propagating precision of the viscous-acoustic medium of the undulating surface in a seismic wave, and when the equation is solved, a mixed space partial derivative difference method is provided to perform solution, and a new boundary condition suitable for an undulating surface curved mesh coordinate system is provided to absorb artificial boundary reflection.

The invention provides a frequency domain visco-acoustic medium full waveform inversion method, which comprises the steps of using a truncated Newton method to perform a joint inversion on velocity and a Q value, and selecting an optimized hybrid interleaving difference format to discretize a wave equation. The method of the invention improves the artifact phenomenon and improves the effect and efficiency of the joint inversion.

An ultrasonic probe according to the present invention includes: an ultrasonic element unit for transmitting and receiving an ultrasonic wave while carrying out ultrasonic scanning; a storage portion for storing the ultrasonic element unit; and an acoustic medium liquid charged in the storage portion. The ultrasonic element unit is supported by an elastic supporting member, and the storage portion is sealed by the supporting member in a liquid-tight state.

An ultrasonic probe is configured such that: a piezoelectric element group is housed within a sealed container so as to be rotated and oscillated left and right about a center line that equally divides a plate surface of the piezoelectric element group; and the sealed container is filled with a liquid that serves as an acoustic medium, and in the sealed container there are provided an inlet hole for the liquid as well as an exhaust hole, to the inlet hole there is connected a flexible tube that functions as a diaphragm, and on the flexible tube and the exhaust hole there are respectively provided sealing lids. As a result, there is provided an ultrasonic probe that prevents an occurrence of air bubbles in a liquid that serves as an ultrasonic wave medium, and that realizes excellent ultrasonic characteristics.

The invention discloses a spherical transmission wave characteristic analysis method and a computer readable storage medium. The method comprises the following steps of calculating a spherical wave transmission wave field of a receiving point based on an acoustic medium model; calculating a virtual seismic source incident wave field of the receiving point, wherein the virtual seismic source incident wave field is set to be the same as a spherical wave transmission wave field in propagation path; calculating a spherical wave transmission coefficient according to the spherical wave transmissionwave field and the virtual seismic source incident wave field; and analyzing the spherical wave characteristics according to the spherical wave transmission coefficient. According to the invention, the spherical wave transmission characteristics are analyzed through the calculated spherical wave transmission coefficient, so that the propagation characteristics and rules of the spherical waves in the medium are better researched and analyzed based on the spherical wave theory of the point source, a more accurate seismic exploration method technology is further developed, and the method has thevery important theoretical value and practical significance for the spherical wave theory of the point source.

The invention provides an ultrasonic transducer acoustoelectric closed-loop impedance measuring method and device. According to the method, in measurement, when an ultrasonic transducer is in an acoustoelectric conversion state, a transmitted broadband signal is converted into a sound signal through a transmitting ultrasonic transducer, the sound signal goes through an acoustic medium and is converted into an electric signal by a receiving ultrasonic transducer, and an acoustoelectric closed-loop measuring circuit from an electric signal to a sound signal and then to an electric signal is formed. Through calculating the acoustoelectric closed-loop channel response of a broadband range, through an equivalent circuit of the acoustoelectric closed-loop channel, the parameter of each element in an ultrasonic transducer closed-loop equivalent circuit is fitted, and thus the impedance of the ultrasonic transducer is obtained. The device comprises a data processing background, a measurement transmitting module, the acoustic medium, and a measurement receiving module. The device of the invention is simple, and a measurement result is the impedance of the ultrasonic transducer in the acoustoelectric conversion state and has a more practical reference value.

An optical microphone includes: a light source; a first polarizer for allowing linearly-polarized light, of light output from the light source, to pass therethrough; a second polarizer for allowing linearly-polarized light having a different polarization plane from the first polarizer to pass therethrough; a sound-receiving section including an acoustic medium having a smaller sound velocity than the air, wherein an acoustic signal propagates through the acoustic medium, the sound-receiving section being arranged so that the linearly-polarized light from the first polarizer passes through the acoustic medium and enters the second polarizer; and a photodetector for converting an intensity of light having passed through the second polarizer to an electric signal, wherein between the first polarizer and the second polarizer, the linearly-polarized light having passed through the first polarizer is given different phase shifts in two orthogonal directions which are each different from a polarization direction.

Air flow openings in a machine housing facilitate air exchange with a machine, but may become outlets for machine noise. In order to protect a machine from possibly damaging elements while facilitating air exchange and attenuating machine noise, the present disclosure includes a machine that is, at least, partially surrounded by a machine housing. An acoustic media grille is positioned adjacent to at least a portion of the machine housing. The acoustic media grille and the portion of the machine housing both define air flow openings that, at least partially, correspond with one another to form an at least partially unobstructed air flow path.

The embodiment of the invention discloses an imaging method and device in a visco-acoustic medium. The method comprises the steps: carrying out the linearization of an original wave equation based onthe least square inversion theory via Born approximation according to to-be-imaged medium parameters; building an inverse migration operator corresponding to reverse time migration; building an objective function of least square migration under an inverted theoretical framework, and deducing an iterative inversion algorithm through an adjoint state method, thereby achieving the least square inverse migration of the visco-acoustic medium. During the inversion imaging of the seismic data of the visco-acoustic medium, the method effectively improves the imaging precision of a geologic body underthe complex medium conditions, reasonably eliminates the impact on the amplitude, frequency and phase from the stratum absorption, transmission and geometric diffusion, and achieves the amplitude-preserving, fidelity-preserving and higher-resolution imaging.

The invention relates to a method for photoetching piezoelectric film transducers on two sides of an acoustic bulk wave, which comprises the following steps: 1) manufacturing a two-side photoetching mask for a bottom electrode, a piezoelectric film for alignment and an upper electrode mask according to electrode patterns on each layer of the designed bottom electrode, piezoelectric film and upper electrode; 2) forming metal films for the bottom electrode at two ends of an acoustic transmission medium; 3) photoetching the bottom electrode patterns on two sides of the metal films of the bottom electrode; 4) sputtering the piezoelectric films at two ends of the acoustic transmission medium; 5) evaporating or sputtering the upper electrode films at two ends of the acoustic transmission medium; 6) manufacturing patterns of the piezoelectric film by alignment; and 7) manufacturing patterns of the upper electrode by alignment. The method solves the problems that a mechanism mask has small size and the pattern of the mask cannot be printed, and the manufactured patterns lack of standardization and have poor precision, and the like. Therefore, the precision of the mask and the consistency of the electrode patterns can reach micron dimension; the acoustic transmission medium has wider dimension range; and the aligned precision at two ends in the range from 2 to 90mm is high, and the alignment can be less than 5 microns.

The invention discloses a Korotkoff's sound sensor. The Korotkoff's sound sensor comprises a sensor monitoring probe, wherein the sensor monitoring probe is positioned at an end of the Korotkoff's sound sensor and comprises a supporting base with a cavity structure in the middle; upward flanges are arranged at two ends of the supporting base; a step structure which is higher than a plane of the cavity structure is formed on the supporting base; a piezoelectric metal substrate is fixedly supported on the step structure; a stress acoustic medium transmitting unit is adhered to the upper surface of the metal substrate; a piezoelectric sensor is solidified on the lower surface of the metal substrate; signal processing circuits are arranged below the piezoelectric sensor and in the cavity structure at intervals; and each signal processing circuit is provided with an output end; and signals can be transmitted from the output ends of the signal processing circuits to an external Korotkoff's sound hematomanometer. The problem that the original Korotkoff's sound sensor is poor in anti-interference performance, low in sound intensity and not high in frequency resolution is solved.

The invention provides a prestack depth reverse time migration imaging method of an absorption attenuation medium. The method comprises the steps of: step 1: giving initial values of L strain fittingparameters T sigma 1 within an effective frequency band range of seismic data; step 2: calculating an integral function value at the current calculation frequency based on the initial values of the Lstrain fitting parameters T sigma 1; step 3: obtaining a stress fitting parameter T corresponding to a current Q value according to a fitting parameter expression; step 4: in view of all Q value points in a Q value field data, repeating the step 1 to the step 3 to obtain a fitting parameter data body; step 5: obtaining a sticky acoustic medium wave field forward propagation operator and a sticky acoustic medium wave field reverse propagation operator, and performing forward modelling of a wave field according to the forward propagation operator and the reverse propagation operator to obtain ashot point forward propagation wave field and a detection point reverse propagation wave field; and step 6: performing imaging by using imaging conditions for the shot point forward propagation wave field and the detection point reverse propagation wave field of any moment. By adopting the prestack depth reverse time migration imaging method provided by the invention, the efficiency of prestack depth reverse time migration imaging is greatly improved under the condition of ensuring the imaging accuracy.