66 results about "Resonance frequency shift" patented technology

A non-contact wireless communication apparatus and a mobile terminal apparatus are provided. The non-contact wireless communication apparatus includes a non-contact wireless communication antenna, a resonance capacitor, connected in parallel with the non-contact wireless communication antenna, for obtaining a predetermined resonance frequency with the non-contact wireless communication antenna, a resonance frequency adjustment unit for changing a resonance capacitance of the resonance capacitor to adjust the resonance frequency, a capacitance change amount control unit for controlling a change in resonance capacitance of the resonance capacitor in the resonance frequency adjustment unit, a resonance frequency shift unit for shifting the resonance frequency of the non-contact wireless communication antenna, and on/off control unit for performing on/off control of the resonance frequency shift unit in accordance with the amount of change in resonance capacitance of the resonance capacitor by the capacitance variation control unit.

Multi-energy radiation sources comprising charged particle accelerators driven by power generators providing different RF powers to the accelerator, capable of interlaced operation, are disclosed. Automatic frequency control techniques are provided to match the frequency of RF power provided to the accelerator with the accelerator resonance frequency. In one example where the power generator is a mechanically tunable magnetron, an automatic frequency controller is provided to match the frequency of RF power pulses at one power to the accelerator resonance frequency when those RF power pulses are provided, and the magnetron is operated such that frequency shift in the magnetron at the other power at least partially matches the resonance frequency shift in the accelerator when those RF power pulses are provided. In other examples, when the power generator is a klystron or electrically tunable magnetron, separate automatic frequency controllers are provided for each RF power pulse. Methods and systems are disclosed.

A piezoelectric cantilever with a non-piezoelectric, or piezoelectric tip useful as mass and viscosity sensors. The change in the cantilever mass can be accurately quantified by monitoring a resonance frequency shift of the cantilever. For bio-detection, antibodies or other specific receptors of target antigens may be immobilized on the cantilever surface, preferably on the non-piezoelectric tip. For chemical detection, high surface-area selective absorbent materials are coated on the cantilever tip. Binding of the target antigens or analytes to the cantilever surface increases the cantilever mass. Detection of target antigens or analytes is achieved by monitoring the cantilever's resonance frequency and determining the resonance frequency shift that is due to the mass of the adsorbed target antigens on the cantilever surface. The use of a piezoelectric unimorph cantilever allows both electrical actuation and electrical sensing. Incorporating a non-piezoelectric tip (14) enhances the sensitivity of the sensor. In addition, the piezoelectric cantilever can withstand damping in highly viscous liquids and can be used as a viscosity sensor in wide viscosity range.

In a method and magnetic resonance (MR) imaging apparatus for reducing artifacts due to resonance frequency offsets in a diagnostic MR image, a number of MR scout images of a portion of a subject containing a region of interest (ROI) are generated respectively using different radio frequency (RF) excitation frequencies. Each of the MR scout images has an identifiable image quality in the ROI. The MR scout images are analyzed as to the image quality in the ROI to identify one of the MR scout images having the best image quality in the ROI. An MR diagnostic image is then generated of the portion of the subject containing the ROI, using the RF excitation frequency that was used to generate the MR scout image having the best image quality in the ROI.

A method of decreasing resonant frequency shifting of an electrical circuit mounted on a vehicle key includes providing a frame in an opening in the head portion of a vehicle key and locating the transponder in the frame. The frame comprises substantially rigid non-metallic material, and the frame includes a support structure for supporting the transponder while decreasing forces produced on the transponder by thermal expansion and contraction of the head portion of the key, thereby decreasing shift in the resonance of the electrical circuit of the transponder. The frame, the transponder and the head portion of the key are overmolded providing an outer covering that encloses and protects the transponder.

The invention relates to a terahertz non-bianisotropic metamaterial unmarked sensor, and a preparation method and a use thereof, and belongs to the biotechnical field. The unmarked sensor comprises aflexible substrate polyimide, a metal layer is arranged on the flexible substrate polyimide, the metal layer comprises a lower titanium metal layer having a thickness of 20 nm and an upper gold metallayer having a thickness of 200 nm, the titanium metal layer is arranged on the flexible substrate polyimide, and the metal layer is a metal resonance ring with two openings. The asymmetric metal resonance ring with two openings is designed to realize electromagnetic induction of a transparent formant, the surface of a metamaterial is inoculated with cells through cell culture, the resonance frequency shift of a device is detected in a back transmission manner, and the theoretic sensitivity reaches up to 455 GHz/RIU, so the concentration of cancer cells can be rapidly preliminarily detected inan unmarked manner, and the apoptosis trend of oral cancer cells HSC3 under different anticancer drug action times is obtained.

A grammage measuring apparatus includes a dielectric resonator which is arranged only at one surface side of a sample; a shielding container with which the dielectric resonator is substantially covered except for a sample measuring surface; a microwave excitation device which causes the dielectric resonator to generate an electric field vector; a detection device which detects transmission energy or reflection energy by the dielectric resonator; a storage device in which a calibration curve indicating a resonance frequency shift amount for a grammage is stored; and a data processing device which calculates the grammage of a measuring sample from the calibration curve and measurement result of the resonance frequency shift amount of the measuring sample.

A first-order perturbation theory similar to the one widely used in quantum mechanics is developed for transverse-electric and transverse-magnetic photonic resonance modes in a dielectric microsphere. General formulas for the resonance frequency shifts in response to a small change in the exterior refractive index and its radial profile are derived. The formulas are applied to two sensor applications of the microsphere to probe the medium in which the sphere is immersed: a refractive index detector; and a refractive index profile sensor.

Disclosed is a method of detecting the presence of an oligomer analyte in a liquid sample, the method comprising the steps of: (a) contacting a sample comprising the oligomer or aggregate with an oscillating sensor surface, which surface may optionally be coated with a receptor that binds directly or indirectly to at least one component of the oligomer or aggregate, so as to cause direct or indirect binding of the oligomer or aggregate to the surface; (b) using a detection circuit to measure or calculate at least two of the following parameters: series resonance frequency (f₀), and hence the series resonance frequency shift (ΔF); motional resistance (R_M), and hence the motional resistance shift ΔR; motional inductance (L_M); motional capacitance (C_M); parallel capacitance (C₀); frequency half-band half-width (Γ); Q-factor (=f/(2Γ); dissipative factor (1/Q); impedance or admittance phase (φ) and hence phase shift (Δφ); and impedance or admittance amplitude (Z, or Y) and hence amplitude change (ΔZ, or ΔY); (c) and analysing the calculated values to derive data which vary according to the presence and/or amount of oligomer in the sample; (d) and, optionally, repeating the measurements continuously or intermittently to derive data which vary according to the presence and/or amount of oligomer or aggregate in the sample to be calculated as a function of elapsed time.

There is provided an atomic force microscope (AFM) with increase the speed and sensitivity of detection of the resonant frequency shift in a cantilever. An AFM (1) extracts a reference signal and a phase shift signal from a detection signal from a displacement sensor of the cantilever. The reference signal is restrained from a phase change in accordance with the resonant frequency shift. The phase shift signal has a phase shifted in accordance with the resonant frequency shift. The AFM (1) determines the phase difference of the phase shift signal from the reference signal, as the resonant frequency shift. The AFM (1) may detect the phase difference between a plus-minus inversion point on the reference signal and a corresponding plus-minus inversion point on the phase shift signal. The AFM (1) may adjust phase before phase detection. The phase adjustment may move the detection point for the resonant frequency shift defined on the oscillation waveforms to the plus-minus inversion point. The detection point is set at a position where the cantilever and a sample are closest to each other on the oscillation waveform.

A dielectric sensing method and apparatus are provided for detection and classification of chemical and biological materials. Resonance patterns of a sample within a resonator are detected for identifying a shift in resonance frequency and a change of line width before and after introduction of the sample. The identified shift in resonance frequency and change of line width are used for determining a complex dielectric constant of the sample for the material detection and classification. A degree of selectivity at any excitation frequency is enabled for the dielectric sensing method from the manner in which the complex dielectric constant of a material affects the resonance pattern of the resonator with respect to shift in resonance frequency and the change in line width. By selecting the excitation frequencies to generally correspond to one of the resonance frequencies of the sample material under test, the degree of selectivity and the sensitivity of detection are enhanced.

According to one embodiment, a switch circuit switches a resonance frequency band of an antenna in a display unit between first and second resonance frequency bands. The second resonance frequency band is overlapped with a part of the first resonance frequency band and is higher than the first resonance frequency band. A wireless communication module wirelessly transmits and receives signals using a transmission frequency band and a reception frequency band which are included in the first resonance frequency band. A screen image orientation control module changes an orientation of a screen image displayed on the display unit. A resonance frequency shift module shifts the resonance frequency band of the antenna from the first resonance frequency band to the second frequency band by controlling the switch circuit when the orientation of the screen image is an orientation in which the antenna is positioned on a downward side of the screen image.

An object of the present invention is to provide a whistle which has a resonance frequency shifted to the low-frequency side and a pleasant tone while retaining a compact size and light weight. In order to attain this object, a whistle comprises a mouthpiece portion, inside which an air passageway is formed and in which an air opening is opened, and a body portion, in which a connected resonance chamber that is connected to the air passageway is formed; the connected resonance chamber comprises a first resonance chamber, a second resonance chamber in which a sound-emitting opening is opened, and an orifice connecting the first resonance chamber and the second resonance chamber.