scholarly journals Acoustic Performance Study of Fiber-Optic Acoustic Sensors Based on Fabry–Pérot Etalons with Different Q Factors

Micromachines ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 118
Author(s):  
Jiamin Chen ◽  
Chenyang Xue ◽  
Yongqiu Zheng ◽  
Jiandong Bai ◽  
Xinyu Zhao ◽  
...  
Keyword(s):  
Sound Pressure ◽  
Fiber Optic ◽  
Dynamic Range ◽  
Q Factor ◽  
Acoustic Detection ◽  
Performance Study ◽  
Application Range ◽  
Acoustic Performance ◽  
Fabry Perot ◽  
Q Factors

The ideal development direction of the fiber-optic acoustic sensor (FOAS) is toward broadband, a high sensitivity and a large dynamic range. In order to further promote the acoustic detection potential of the Fabry–Pérot etalon (FPE)-based FOAS, it is of great significance to study the acoustic performance of the FOAS with the quality (Q) factor of FPE as the research objective. This is because the Q factor represents the storage capability and loss characteristic of the FPE. The three FOASs with different Q factors all achieve a broadband response from 20 Hz to 70 kHz with a flatness of ±2 dB, which is consistent with the theory that the frequency response of the FOAS is not affected by the Q factor. Moreover, the sensitivity of the FOAS is proportional to the Q factor. When the Q factor is 1.04×106, the sensitivity of the FOAS is as high as 526.8 mV/Pa. Meanwhile, the minimum detectable sound pressure of 347.33 μPa/Hz1/2  is achieved. Furthermore, with a Q factor of 0.27×106, the maximum detectable sound pressure and dynamic range are 152.32 dB and 107.2 dB, respectively, which is greatly improved compared with two other FOASs. Separately, the FOASs with different Q factors exhibit an excellent acoustic performance in weak sound detection and high sound pressure detection. Therefore, different acoustic detection requirements can be met by selecting the appropriate Q factor, which further broadens the application range and detection potential of FOASs.

High-resolution, large dynamic range fiber-optic thermometer with cascaded Fabry–Perot cavities

2016 ◽  
Vol 41 (21) ◽  
pp. 5134 ◽  
Author(s):  
Guigen Liu ◽  
Qiwen Sheng ◽  
Weilin Hou ◽  
Ming Han
Keyword(s):  
High Resolution ◽  
Fiber Optic ◽  
Dynamic Range ◽  
Large Dynamic Range ◽  
Fabry Perot

scholarly journals Research on the Frequency Response and Dynamic Range of the Quadrature Fiber Optic Fabry–Perot Cavity Microphone Based on the Differential Cross Multiplication Demodulation Algorithm

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6152
Author(s):  
Baokai Ren ◽  
Jin Cheng ◽  
Longjiang Zhao ◽  
Zhenghou Zhu ◽  
Xiaoping Zou ◽  
...  
Keyword(s):  
Frequency Response ◽  
Differential Cross ◽  
Fiber Optic ◽  
Dynamic Range ◽  
Sampling Rate ◽  
Data Sampling ◽  
Upper Limit ◽  
Fabry Perot ◽  
Quadrature Phase ◽  
Phase Deviation

A quadrature fiber optic Fabry–Perot cavity microphone based on a differential cross multiplication algorithm consists of a pair of fibers and a membrane. It has many advantages such as high sensitivity, a simple structure, and resistance to electromagnetic interference. However, there are no systematic studies on its key performance, for example, its frequency response and dynamic range. In this paper, a comprehensive study of these two key parameters is carried out using simulation analysis and experimental verification. The upper limit of the frequency response range and the upper limit of the dynamic range influence each other, and they are both affected by the data sampling rate. At a certain data sampling rate, the higher the upper limit of the frequency response range is the lower the upper limit of the dynamic range. The quantitative relationship between them is revealed. In addition, these two key parameters also are affected by the quadrature phase deviation. The quadrature phase deviation should not exceed 0.25π under the condition that the demodulated signal intensity is not attenuated by more than 3 dB. Subsequently, a short-step quadrature Fabry–Perot cavity method is proposed, which can suppress the quadrature phase deviation of the quadrature fiber optic Fabry–Perot cavity microphone based on the differential cross multiplication algorithm.

Composite Materials Monitoring by Fiber Optic Sensors

2018 ◽  
Vol 1147 ◽  
pp. 5-11
Author(s):  
Mikhail E. Efimov ◽  
Sergey A. Volkovskiy ◽  
Andrei V. Kulikov ◽  
Vladimir E. Strigalev
Keyword(s):  
Acoustic Emission ◽  
Composite Materials ◽  
Fiber Optic ◽  
Dynamic Range ◽  
Fiber Optic Sensors ◽  
Fabry Perot ◽  
Spectrum Width ◽  
The Impact ◽  
Vertical Cavity ◽  
Diode Current

The paper presents methods for testing the composite materials using two types of fiber-optic sensors as well as a method for using radiation of the vertical-cavity emitting laser radiation (VCSEL) for checking the material deformation and its performances. The deformation checking sensor is a fiber Bragg grating (FBG) with a spectrum width of 50 pm, which is interrogated by the VCSEL. A new algorithm for modulating the laser diode current is proposed for the FBG interrogation providing a dynamic range of at least 3 nm. A new interrogation method of impulse Fabry-Perot interferometer was proposed. The interrogation method was applied for a fiber-optic acoustic emission sensor manufacturing. The sensor was experimentally investigated by the impact of a 6 mm diameter steel ball and compared to a reference piezoelectric acoustic emission transducer.

Influence of the Acoustic Reflex on Vowel Recognition

1986 ◽  
Vol 29 (3) ◽  
pp. 420-424 ◽  
Author(s):  
Michael Dorman ◽  
Ingrid Cedar ◽  
Maureen Hannley ◽  
Marjorie Leek ◽  
Julie Mapes Lindholm
Keyword(s):  
Auditory System ◽  
Sound Pressure ◽  
Dynamic Range ◽  
Recognition Accuracy ◽  
Pressure Level ◽  
Acoustic Reflex ◽  
The Poor ◽  
Stapedial Reflex ◽  
Vowel Recognition ◽  
High Sound

Computer synthesized vowels of 50- and 300-ms duration were presented to normal-hearing listeners at a moderate and high sound pressure level (SPL). Presentation at the high SPL resulted in poor recognition accuracy for vowels of a duration (50 ms) shorter than the latency of the acoustic stapedial reflex. Presentation level had no effect on recognition accuracy for vowels of sufficient duration (300 ms) to elicit the reflex. The poor recognition accuracy for the brief, high intensity vowels was significantly improved when the reflex was preactivated. These results demonstrate the importance of the acoustic reflex in extending the dynamic range of the auditory system for speech recognition.

scholarly journals In-Band Pumped Thulium-Doped Tellurite Glass Microsphere Laser

2021 ◽  
Vol 11 (12) ◽  
pp. 5440
Author(s):  
Elena A. Anashkina ◽  
Vitaly V. Dorofeev ◽  
Alexey V. Andrianov
Keyword(s):  
Tellurite Glass ◽  
High Gain ◽  
Glass Microsphere ◽  
Ion Concentration ◽  
Laser Generation ◽  
Q Factor ◽  
Narrow Line ◽  
Simple Theoretical Model ◽  
Q Factors ◽  
Doped Glass

Microresonator-based lasers in the two-micron range are interesting for extensive applications. Tm3+ ions provide high gain; therefore, they are promising for laser generation in the two-micron range in various matrices. We developed a simple theoretical model to describe Tm-doped glass microlasers generating in the 1.9–2 μm range with in-band pump at 1.55 μm. Using this model, we calculated threshold pump powers, laser generation wavelengths and slope efficiencies for different parameters of Tm-doped tellurite glass microspheres such as diameters, Q-factors, and thulium ion concentration. In addition, we produced a 320-μm tellurite glass microsphere doped with thulium ions with a concentration of 5·1019 cm−3. We attained lasing at 1.9 μm experimentally in the produced sample with a Q-factor of 106 pumped by a C-band narrow line laser.

scholarly journals Low-pressure and liquid level fiber‐optic sensor based on polymeric Fabry–Perot cavity

2021 ◽  
Vol 53 (5) ◽  
Author(s):  
D. Jauregui-Vazquez ◽  
M. E. Gutierrez-Rivera ◽  
D. F. Garcia-Mina ◽  
J. M. Sierra-Hernandez ◽  
E. Gallegos-Arellano ◽  
...  
Keyword(s):  
Fiber Optic ◽  
Low Pressure ◽  
Fiber Optic Sensor ◽  
Liquid Level ◽  
Optic Sensor ◽  
Fabry Perot
Sign in / Sign up

Export Citation Format

Share Document