175results about How to "Oscillation stability" patented technology

A ripple converter includes a transistor for switching an input direct-current voltage, a choke coil and a smoothing capacitor for smoothing the switched direct-current voltage, a flywheel diode for causing a current to flow through the choke coil when the transistor is turned off, and a comparing unit for controlling the ON / OFF of the transistor according to ripple in an output voltage. In the ripple converter, a waveform converter is provided on a connecting path between an output terminal and a non-inverting input terminal of a comparator in the comparing unit. A result of converting the waveform of the output voltage is compared with a reference voltage, and a result of the comparison is fed back to the transistor.

The present invention relates to a counterfeit-proof volume hologram multilayer structure capable of securely preventing a counterfeiter from replicating a volume hologram recorded therein. The multilayer structure comprises a transparent surface protective layer, a volume hologram layer, and an adhesive layer which are sequentially laminated and is characterized in that particles having particle diameter of 350 nm or more are dispersed in at least one of the transparent surface protective layer, the volume hologram layer, and the adhesive layer and that the refractive index ratio (nF / nB) is set to be not less than 1.05 or not greater than 0.95, wherein nF is the refractive index of the particles and nB is the refractive index of the medium in which the particles are dispersed, or characterized in that at least either the refractive index ratio (nP / nH) between the transparent surface protective layer and the volume hologram layer or the refractive index ratio (nH / nA) between the volume hologram layer and the adhesive layer is set to be not less than 1.08, wherein nP is the refractive index of the transparent surface protective layer, nH is the refractive index of the volume hologram layer, and nA is the refractive index of the adhesive layer.

The invention discloses a tunable laser system, a acousto-optic tunable filter that utilizes frequency offset compensation. Precision and stability of the output wavelength are realized by a wavelength lock; the wavelength lock utilizes two separated cavity laser beam to avoid using a beam splitter, which reduces requirements to space comparing to a tradition wavelength lock, and running is more stable, and assembly easier. The acousto-optic tunable filter comprises a acousto-optic crystal and a acoustic wave transducer that are bond on surface selected by a crystal to generate acoustic wave;an optical reflector is used for reflecting the diffracted ray back to the acousto-optic medium; because the two incident rays are opposite relative to the acoustic wave propagation direction, the frequency offset generated by the two diffraction is compensated. The invention can be used to produce wideband tunable laser system for various applications with different laser gain medium, acoustic wave drive frequency and acousto-optic crystal.

A photoelectric oscillator includes a laser beam projection unit; an optical modulator on an optical path extending from the projection unit, which optical modulator outputs a modulated signal or an optical signal containing a harmonic of the modulated signal and includes a modulation electrode whose resonant frequency band includes the frequency band of the modulation signal; a photoelectric converter for converting the output of the optical modulator to an electric signal; a feedback circuit for selecting from the radio-frequency electric signal obtained from the photoelectric converter an electric signal to be re-supplied to the optical modulator; and an output section for outputting an optical signal containing the modulation signal or a harmonic of the modulation signal or outputting the modulation signal or a harmonic of the modulation signal. A laser beam of sufficient intensity is input from the projection unit to produce a radio-frequency electric signal in the feedback circuit, and the radio-frequency electric signal or an optical signal containing the radio-frequency electric signal or the radio-frequency signal is output from the photoelectric oscillator.

Provided is a wavelength tunable external cavity laser comprising: a semiconductor laser diode that outputs multi-wavelength optical signals and is mounted on a first substrate; and a wavelength tunable reflection filter that is mounted on a second substrate, outputs single wavelength optical signals among the multi-wavelength optical signals using resonance of external cavity formed between a semiconductor laser diode and a Bragg-grating having a predetermined period, and tunes the wavelength of the output single wavelength optical signal by varying the refractive index of the Bragg-grating. The wavelength tunable Bragg-grating reflection filter and the semiconductor laser diode are mounted on separate substrates, and the optical coupling efficiency between the semiconductor laser diode and the waveguide type Bragg-grating reflection filter is increased using an active alignment method to increase the optical output power and enable a stable oscillation mode.

Described is an infusion pump comprising electronic infusion regulating means with wired or wireless communication means and a power source, a medicament bag (7) and an infusion device, said infusion device being in fluid communication with said medicament bag (7) and comprising two valves (1, 2), a pressure cavity (4) provided between said two valves (1, 2) and a membrane (3) covering said cavity (4), wherein said infusion device comprises at least two active actuators, preferably either made of electroactive polymer so as to form a self actuating membrane (3) or made of shape memory alloy wire, one of said actuators being adapted to apply pressure to said membrane (3) for fluid displacement in said cavity (4), and the other of said actuators being adapted to operate one of said valves which is adapted to passively close in the flow direction of a fluid from said medicament bag (7) through the cavity (4), wherein the other of said valves is adapted to, in particular passively, close in a direction opposite to said flow direction.

A tunable laser has a multiple ring resonator comprising a plurality of ring resonators having respective ring-shaped waveguides and respective different optical path lengths, an input / output side optical waveguide coupled to the multiple ring resonator, an optical input / output device such as a laser diode coupled to the input / output side optical waveguide, a reflection side optical waveguide coupled to the multiple ring resonator, an optical reflector coupled to the reflection side optical waveguide, a wavelength varying mechanism for changing the resonant wavelength of the multiple ring resonator, and a filter for preventing light in high-order modes from being introduced into the multiple ring resonator and for propagating light in a fundamental mode in the multiple ring resonator.

A tunable laser has a multiple ring resonator comprising a plurality of ring resonators having respective ring-shaped waveguides and respective different optical path lengths, an input / output side optical waveguide coupled to the multiple ring resonator, an optical input / output device such as a laser diode coupled to the input / output side optical waveguide, a reflection side optical waveguide coupled to the multiple ring resonator, an optical reflector coupled to the reflection side optical waveguide for removing light at an unwanted wavelength and reflecting light at a required wavelength, and a wavelength varying mechanism for changing the resonant wavelength of the multiple ring resonator.

The present invention provides a spin torque oscillator that can realize stable oscillation and has high reliability. A laminated structure including a first magnetic layer 1 having a bcc crystal structure and having in-plane magnetic anisotropy and a second magnetic layer 2 having perpendicular magnetic anisotropy laminated on the first magnetic layer 1 and including a multilayer film of Co and Ni is used.

A ripple converter includes a transistor for switching an input direct-current voltage, a choke coil and a smoothing capacitor for smoothing the switched direct-current voltage, a flywheel diode for causing a current to flow through the choke coil when the transistor is turned off, and a comparing unit for controlling the ON / OFF of the transistor according to ripple in an output voltage. In the ripple converter, a waveform converter is provided on a connecting path between an output terminal and a non-inverting input terminal of a comparator in the comparing unit. A result of converting the waveform of the output voltage is compared with a reference voltage, and a result of the comparison is fed back to the transistor.

The invention discloses a high-power all solid-state axisymmetric polarization laser for laser machining. The laser comprises an all solid-state laser generation device. The all solid-state laser generation device comprises a main oscillator for generating a laser beam and a power amplifier for amplifying the output power of the main oscillator, wherein the main oscillator comprises a completely reflecting mirror and an all solid-state single crystal pumping module, which are arranged along the same optical axis; and a polarized light focusing surface is formed between the completely reflecting mirror and the all solid-state single crystal pumping module. The laser also comprises a polarization element which is arranged at a joint of the optical axis between the completely reflecting mirror and the all solid-state single crystal pumping module and the polarized light focusing surface. By the laser, laser in an axisymmetric polarization state can be output, so that the efficiency and accuracy of the laser machining are improved.

A crystal oscillation circuit has a reduced circuit area and enables to stably oscillate at low consumed current. The crystal oscillation circuit includes an oscillating amplifier and a constant voltage generator. The oscillating amplifier excites a resonator composed of a resistor, a crystal oscillator and a capacitor. The constant voltage generator includes a one-stage differential circuit composed of a transistor and a capacitor for suppressing transient fluctuation of a constant voltage Vreg for generating the constant voltage Vreg served as a supply voltage for the oscillating amplifier. By generating the constant voltage Vreg through the one-stage differential circuit, the phase lag of the constant voltage Vreg reaches 90 degrees at most. This eliminates the necessity of a phase compensation capacitor, resulting in making the circuit area smaller and realizing the stable oscillation at low consumed current.