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oe1(光电查) - 科学论文

5 条数据
?? 中文(中国)
  • Study on the Mechanism of Ultrasonic Power Measurement Sensor based on Pyroelectric Effect

    摘要: PVDF pyroelectric sensor has been widely applied in many fields, such as intruder alarm. Nowadays, this sensor shows a potential for ultrasonic power measurement. However, the transformation mechanism between the acoustic and pyroelectric signals has not been particularly studied until now. In this paper, a physical model was introduced for theoretical study of the mechanism of energy transformations. In addition, a simulation program based on finite-element analysis method was built up for analyzing the ultrasound propagation characteristics and the temperature rise on the PVDF, as well it predicted the waveform and amplitude of the generated pyroelectric signal. Besides that, a PVDF pyroelectric sensor was fabricated and used for acoustic power measurement experiment. Finally, the experiment and simulation results were compared, confirming that the physical model is suitable for pyroelectric sensor characteristics analysis. It can also provide useful suggestions for the design and fabrication of PVDF pyroelectric sensors with high sensitivity.

    关键词: ultrasonic power,PVDF,finite-element analysis,pyroelectric sensor

    更新于2025-09-19 17:15:36

  • [IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - Multi-wavelength DFB laser array in InAs/GaAs quantum dot material epitaxially grown on Silicon

    摘要: A ?rst proof-of-concept mm-sized implantable device using ultrasonic power transfer and a hybrid bi-directional data communication link is presented. Ultrasonic power transfer enables miniaturization of the implant and operation deep inside the body, while still achieving safe and high power levels (100 W to a few mWs) required for most implant applications. The current implant prototype measures 4 mm 7.8 mm and is comprised of a piezoelectric receiver, an IC designed in 65 nm CMOS process and an off-chip antenna. The IC can support a maximum DC load of 100 W for an incident acoustic intensity that is 5% of the FDA diagnostic limit. This demonstrates the feasibility of providing further higher available DC power, potentially opening up new implant applications. The proposed hybrid bi-directional data link consists of ultrasonic downlink and RF uplink. Falling edge of the ultrasound input is detected as downlink data. The implant transmits an ultra-wideband (UWB) pulse sequence as uplink data, demonstrating capability of implementing an energy-ef?cient M-ary PPM transmitter in the future.

    关键词: implantable biomedical devices,active recti?er,mm-sized implants,ultrasonic power transfer,piezoelectric receivers,bi-directional data communication,CMOS,antennas,IMD,AC-DC converter,radio transmitters

    更新于2025-09-19 17:13:59

  • [IEEE 2019 IEEE 4th International Conference on Image, Vision and Computing (ICIVC) - Xiamen, China (2019.7.5-2019.7.7)] 2019 IEEE 4th International Conference on Image, Vision and Computing (ICIVC) - A Method for Generating Spray Trajectory of a Shoe Sole Based on Laser Vision

    摘要: A ?rst proof-of-concept mm-sized implantable device using ultrasonic power transfer and a hybrid bi-directional data communication link is presented. Ultrasonic power transfer enables miniaturization of the implant and operation deep inside the body, while still achieving safe and high power levels (100 W to a few mWs) required for most implant applications. The current implant prototype measures 4 mm 7.8 mm and is comprised of a piezoelectric receiver, an IC designed in 65 nm CMOS process and an off-chip antenna. The IC can support a maximum DC load of 100 W for an incident acoustic intensity that is 5% of the FDA diagnostic limit. This demonstrates the feasibility of providing further higher available DC power, potentially opening up new implant applications. The proposed hybrid bi-directional data link consists of ultrasonic downlink and RF uplink. Falling edge of the ultrasound input is detected as downlink data. The implant transmits an ultra-wideband (UWB) pulse sequence as uplink data, demonstrating capability of implementing an energy-ef?cient M-ary PPM transmitter in the future.

    关键词: piezoelectric receivers,bi-directional data communication,mm-sized implants,CMOS,ultrasonic power transfer,active recti?er,IMD,antennas,radio transmitters,AC-DC converter,implantable biomedical devices

    更新于2025-09-19 17:13:59

  • Ultrasound-assisted electrodeposition of Fe-Ni film for OLED mask

    摘要: Fe-Ni alloy is considered as the most suitable metal for OLED mask making due to its excellent properties. However, electrodeposited Fe-Ni ?lm is often companied with poor surface quality and thermal expansion. To get proper ?lm for masks making, experiments of electroforming Fe–Ni were performed with di?erent ultrasonic powers and current densities. Results show that Fe-Ni ?lm with smooth surface could be electrodeposited at high current density due to the reducing of internal stress of ?lm by ultrasonic power. The iron content, grain size, micro-hardness and Young’s modulus of ?lm all present an upward trend with ultrasonic power increases from 13 W to 93 W, and then a downward trend due to the intensively transient cavitation caused by higher ultrasonic power 120 W. With the ultrasonic power of 93 W and current density of 1 A/dm2, a good surface quality of Fe-Ni ?lms with 60.07 wt.% iron content, microhardness 351 HV, Young's modulus 167.5 GPa and CTE 3.38 × 10?6/℃ can be electrodeposited.

    关键词: Fe-Ni ?lm,Electroforming,Young's modulus,Ultrasonic power,Thermal expansion

    更新于2025-09-19 17:13:59

  • [IEEE 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Waikoloa Village, HI (2018.6.10-2018.6.15)] 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Cathodoluminescence Characterization of Semiconductor Doping at the Nanoscale

    摘要: PVDF pyroelectric sensor was widely used in many fields. At present, the PVDF pyroelectric sensor has been applied for acoustic measurement. However, the effect of backing on the sensitivity of sensor was not particularly studied until now. In this paper, a Physical model was established in the finite element software. According to this model, the waveform of pyroelectric signal was predicted. By changing the parameters of the backing material, the influence of the backing on the sensitivity of the sensor was analyzed. It is confirmed that the Physical model is effective and the constant pressure heat capacity, attenuation coefficient and acoustic impedance of backing material directly affect the sensitivity of the sensor.

    关键词: PVDF pyroelectric sensor,backing material,ultrasonic power,sensitivity

    更新于2025-09-11 14:15:04