210 results about "Quartz tuning fork" patented technology

The invention discloses a quartz tuning fork photoacoustic gas sensing device based on a broadband light source dual-wavelength difference. A pipy resonant cavity with a slit and a quartz tuning fork are arranged in a sample pool. In the device, a laser diode is used for probing non absorption background noise, the other laser diode is used for probing nitrogen dioxide, coupling and beam splitting are carried out on the two laser diodes through a beam splitting prism, a photoelectric probe is used for monitoring the power of the laser diodes, light is focused to the pipy resonant cavity by a focusing lens, the output end of the quartz tuning fork is connected with the input end of a phase-locked amplifier, the focus of the focusing lens is arranged in the pipy resonant cavity, the output end of a high frequency square wave generator is electrically connected with the input end of the phase-locked amplifier, and the photoelectric probe, the high frequency square wave generator and a lower frequency square wave generator are connected with an external computer.

The invention relates to an enhanced multi-group photoacoustic spectrum gas sensing device based on a quartz tuning fork and belongs to the field of a photoacoustic spectrum detection technology. According to the invention, the quartz tuning fork with high quality factor is used to replace a traditional broadband microphone so as to broaden the dynamic range and realize miniaturization of the whole gas sensing device. By arranging a fiber-optic amplifier between a light source and an optical fiber coupler, laser output power of the light source is increased. Thus, it is easy to capture a weak photoacoustic signal generated by the quartz tuning fork, and detection sensitivity of the gas sensing device can be enhanced.

The invention discloses a quartz tuning-fork enhanced-type photo-acoustic spectrum gas cell, which comprises a first c-lens collimating lens (4), a second c-lens collimating lens (1), a first resonance tube (3), a second resonance tube (2), a quartz tuning fork (7), a dual V-shaped groove fixed seat (8) and a substrate (9), wherein a light path emitted from the second c-lens collimating lens (1) reaches the first c-lens collimating lens (4) after passing through the second resonance tube (2), the finger clearance of the quartz tuning fork (7) and the first resonance tube (3). The c-lens collimating lenses are adopted in the gas cell, so that the light beam can completely pass through the resonance tubes and the quartz tuning fork, the loss of the light beam in incidence can be avoided, and the sensitivity of the gas cell can be improved. Meanwhile, by the adoption of the c-lens collimating lenses, collimating focus is not needed between the light source and the gas cell, so that the size of the photo-acoustic spectrum gas detection device is reduced.

The invention discloses a three-dimensional resonance trigger probe based on a quartz tuning fork and a three-dimensional resonance trigger location method. The three-dimensional resonance trigger probe is characterized in that the quartz tuning fork is used as a micro force sensor, a piezoelectric driver is fixed on a fork arm of the quartz tuning fork, a piezoelectric sensor is fixed on the other fork arm; the quartz tuning fork is vertical to the surface of a sample in the vibration direction on the Z direction and is parallel to the surface of the sample in the vibration direction on X and Y directions, an integrated micro measuring bar measurement ball is fixedly arranged on the fork arm close to one side where the sample is in, and a sine alternating-current signal output by a phase-locked loop is applied to the piezoelectric sensor as an excitation signal, and a fork resonance signal is detected by the piezoelectric sensor. When a micro three-dimensional external force causes that the resonance frequency of the probe changes, the resonance frequency of a quarts tuning fork probe changes, and three-dimensional resonance trigger location of the three-dimensional resonance trigger probe is realized through detecting the change of the resonance frequency of the quartz tuning fork.

The invention relates to a high-sensitivity MEMS resonant temperature sensor chip, and belongs to the technical field of MEMS temperature sensors. The chip comprises a quartz glass annular base and aquartz crystal resonance layer, the quartz crystal resonance layer comprises a rhombic force amplification resonator, a first quartz arm, a second quartz arm, a first anchor point and a second anchorpoint; the rhombus force amplification resonator comprises a rhombus ring and a double-end clamped quartz tuning fork; the first anchor point, the first quartz arm, the second quartz arm and the second anchor point are positioned on a short diagonal line of the rhombus ring; and the double-end clamped quartz tuning fork is positioned on the long diagonal line of the rhombus ring. When the temperature of a measured environment changes, the quartz crystal resonance layer generates thermal expansion deformation due to restriction of the annular base, large axial stress is generated in the pair ofquartz arms, and the large axial stress is amplified by the rhombic ring to act on the double-end clamped quartz tuning fork. The sensitivity of the sensor and the stability of the resonance frequency are remarkably improved, and the sensor has the advantages of being simple in structure, high in anti-interference capacity and the like.

A double-tube side-by-side type quartz tuning-fork enhancing type photoacoustic spectrometry detection apparatus comprises a laser, a focusing lens, a collimating lens, a gas sample pool, a lock-in amplifier, a laser controller, a function generator, a control hose, a frequency tracking controller, and a preamplifier electrically connected with a quartz tuning fork output terminal. Two same optical paths are respectively subjected to collimation and focusing, then enter miniature tubes, are focused at the focus at the central parts of the miniature tubes, and respectively generate opto-acoustic signals. The gas sample pool is provided with a mounting base, two miniature tubes are symmetrically arranged at the sidewalls of the mounting base, the quartz tuning fork is arranged at the bottom of the mounting base, and the tuning fork arm of the quartz tuning fork is parallel to or perpendicular to the miniature tubes. The central position of each miniature tube is provided with a slit corresponding to a notch or the tuning fork arm of the quartz tuning fork, and when working, the quartz tuning fork is subjected to the sound pressure effect of the miniature tubes at two sides at the same time, and the signal intensity is enhanced. The apparatus also is provided with a constant-temperature water hole at the bottom of the mounting base for keeping quartz tuning fork properties stable.

A silicon substrate quartz acceleration sensor with a temperature isolation structure comprises a silicon substrate and a double end fixed quartz tuning fork, wherein a mass block on the silicon substrate is connected with the silicon substrate through two flexible beams, a groove is etched in the portion, on the same side of the flexible beams, of the surface of the silicon substrate, the two ends of the groove are respectively connected with a cavity, on the side of the flexible beams, of the mass block and a cavity below the temperature isolation structure, the temperature isolation structure is composed of a fixing seat and a supporting beam, a supporting seat at one end of the double end fixed quartz tuning fork is fixed on the fixing seat of the temperature isolation structure, a supporting seat at the other end of the double end fixed quartz tuning fork is fixed on the mass block, two fork teeth of the double end fixed quartz tuning fork are connected with the supporting seats through fixing ends, and an electrode is covered on the periphery of the fork teeth. When acceleration has an effect on the sensor, the mass block supported by the flexible beams generates displacement to pull or press the double end fixed quartz tuning fork to change vibration frequency of the double end fixed quartz tuning fork and achieve the measurement of the acceleration by the quartz. The temperature isolation structure of the silicon substrate quartz acceleration sensor can reduce the effect of low temperature on the accuracy of the sensor.