摘要:
A surface acoustic wave element includes a single crystal base which has an annular surface formed by at least one portion of a spherical surface, and an exciting unit which excites a surface acoustic wave propagating along the annular surface. An electric signal processing apparatus includes the surface acoustic wave element, an input portion which inputs a predetermined signal to the exciting unit so that the wave is excited, a detecting unit which detects the propagating wave, and an output portion which outputs a signal corresponding to the wave detected by the detecting unit. An environment evaluating apparatus includes the processing apparatus, and a processing portion which evaluates an environment around the base, based on at least one of a frequency of the signal outputted by the processing apparatus, an intensity thereof, and time elapsing from a signal input time to a signal output time from the processing apparatus.
摘要:
The present invention relates to an elastic surface-wave device, and more particularly to an elastic surface-wave device of a greatly increased performance, compared with a prior art elastic surface-wave device, and which is compact. The elastic surface-wave device includes a substrate including a surface having a region which is formed by at least a part of a spherical surface and is circularly continuous, and a surface acoustic wave generator which is provided in the surface region of the substrate and generates surface acoustic waves propagating in a continuous direction of the surface region. The surface acoustic wave generator generates surface acoustic waves in such a manner these waves can propagate only in the continuous direction without being diffused in a direction crossing the continuous direction along the surface region.
摘要:
An ultrasonic sensor for use in an ultrasonic micro spectrometer includes a concave surface transducer having a concave ultrasonic wave transmitting/receiving surface and a plane transducer having a plane transmitting/receiving surface. The concave surface transducer is capable of transmitting converging ultrasonic waves toward a specimen, wherein the waves are reflected from the surface of the specimen and are received by the plane transducer which outputs electric signals corresponding to the intensity of the reflected ultrasonic waves. Based on a signal output from the ultrasonic sensor, a digital oscilloscope and FFT analyzer forms a distribution of spectral intensity indicating the intensity of the reflected wave as a function of frequency. The digital oscilloscope and FFT analyzer further forms a distribution of spectral phase indicating the spectral phase of the reflected waves as a function of frequency. Either the distribution of spectral intensity or of spectral phase can effectively be analyzed for evaluating elastic characteristics and structure of a specimen.
摘要:
In a method and an apparatus for exciting acoustic waves, the surface of an object is irradiated with coherent parallel energy beams and coherent focusing energy beams which have different frequencies in such a manner that they overlap each other to generate interference fringes (concentric circles) propagating from outside to the inside at propagation speed which is higher than a specific acoustic speed of the object. The acoustic waves are excited in accordance with distortion distribution generated in the surface of the object attributable to the photo-thermal effect of the interference fringes, the acoustic waves being focused to a small region in the object, the position of which is determined by the specific acoustic speed of the object and the propagation speed of the interference fringes.
摘要:
Various ultrasonic transducer assemblies are disclosed in which each assembly includes a pair of ultrasonic transducers for emitting or receiving an ultrasonic wave, respectively, and wherein the ultrasonic transducers include a concave shaped ultrasonic transducer and a flat shaped ultrasonic transducer. The ultrasonic transducer assemblies realize excellent magnitude of accuracy, resolving power, versatility and simplicity in handling. In addition, various ultrasonic acoustic microscopes are disclosed incorporating the aforementioned ultrasonic transducer assemblies and realizing the same results thereof.
摘要:
A method of measuring the rate of transmission of a vapor through a test sample using a mass spectrometer. The test sample is sealed to a gas cell defining a gas chamber, covering an opening in the gas chamber. A droplet of water including isotopes of mass number placed in the gas chamber and the gas cell is introduced into a vacuum chamber adjacent a mass spectrometer. After a sufficient time for evaporation of the liquid to saturate the gas chamber with vapor and for the output of the mass spectrometer to stabilize, the partial pressure of vapor in the vacuum chamber is measured using the mass spectrometer. The measure partial pressure is used to derive the rate of transmission of the vapor through the test sample.
摘要:
A speech analysis apparatus according to the invention, comprising a transforming section for receiving a spectrum envelope, for transforming the spectrum envelope such magnitude data thereof becomes suitable, and for generating a transformed spectrum envelope, an integrator for receiving the transformed spectrum envelope output from the transforming section, for integrating the input spectrum envelope with respect to a predetermined variable, and for outputting an integrated spectrum envelope, and a projection circuit for receiving the transformed spectrum envelope from the transform circuit and the integrated spectrum envelope from the integrator, and for projecting the spectrum envelope with respect to the integrated data. Therefore, the analysis result inherent to the phoneme can be obtained regardless of vocal tract lengths. The spectrum envelope to be projected can be integrated by the integrator, along the frequency axis or the mel axis. The analysis apparatus further includes a spectrum envelope-extractor for obtaining the spectrum envelope, by using cepstrum analysis and smoothing the resultant spectrum envelope. A spectrum envelope in the transition from a consonant to a vowel can be obtained.