An optomechanical accelerometer with a high-finesse hemispherical optical cavity

Chen

et al. 2020

Sensors

This paper reviews the research and development of micromachined accelerometers with a noise floor lower than 1 µg/√Hz. Firstly, the basic working principle of micromachined accelerometers is introduced. Then, different methods of reducing the noise floor of micromachined accelerometers are analyzed. Different types of micromachined accelerometers with a noise floor below 1 µg/√Hz are discussed. Such sensors can mainly be categorized into: (i) micromachined accelerometers with a low spring constant; (ii) with a large proof mass; (iii) with a high quality factor; (iv) with a low noise interface circuit; (v) with sensing schemes leading to a high scale factor. Finally, the characteristics of various micromachined accelerometers and their trends are discussed and investigated.

Section: Mems Accelerometers With Signal Readout Methods Of Highermentioning

confidence: 99%

“…A noise floor of better than 10 ng/√Hz over a bandwidth of 2 kHz was achieved above 9 kHz. Bao et al [85] Hz. It consisted of a G-shaped mass-spring structure sensing chip, laser diode, cube beam splitter and photo translating system, which were integrated by a 3D printed sensor package.…”

mentioning

confidence: 97%

Micromachined Accelerometers with Sub-µg/√Hz Noise Floor: A Review

Chen

et al. 2020

Sensors

“…Cavity optomechanics 98−102 has attracted increasing research interest for both fundamental studies and practical applications, and this paves the way for highly sensitive Fabry-Perot cavity based accelerometers. Cervantes et al 103 presented a modified Fabry-Perot cavity based accelerometer that combines a monolithic fused quartz oscillator and a fiber micro-cavity together, in which the oscillator is of low-loss and compatible with optical cavity. This type of accelerometer can reach a sensitivity of 100…”

Section: V-beam Amplifiermentioning

confidence: 99%

Review of micromachined optical accelerometers: from m<i>g</i> to sub-μ<i>g</i>

et al. 2021

OEA

Micro-Opto-Electro-Mechanical Systems (MOEMS) accelerometer is a new type of accelerometer which combines the merits of optical measurement and Micro-Electro-Mechanical Systems (MEMS) to enable high precision, small volume and anti-electromagnetic disturbance measurement of acceleration. In recent years, with the in-depth research and development of MOEMS accelerometers, the community is flourishing with the possible applications in seismic monitoring, inertial navigation, aerospace and other industrial and military fields. There have been a variety of schemes of MOEMS accelerometers, whereas the performances differ greatly due to different measurement principles and corresponding application requirements. This paper aims to address the pressing issue of the current lack of systematic review of MOEMS accelerometers. According to the optical measurement principle, we divide the MOEMS accelerometers into three categories: the geometric optics based, the wave optics based, and the new optomechanical accelerometers. Regarding the most widely studied category, the wave optics based accelerometers are further divided into four sub-categories, which is based on grating interferometric cavity, Fiber Bragg Grating (FBG), Fabry-Perot cavity, and photonic crystal, respectively. Following a brief introduction to the measurement principles, the typical performances, advantages and disadvantages as well as the potential application scenarios of all kinds of MOEMS accelerometers are discussed on the basis of typical demonstrations. This paper also presents the status and development tendency of MOEMS accelerometers to meet the ever-increasing demand for high-precision acceleration measurement.

“…In the wave-optics-based accelerometers, the acceleration alters the parameters of the light flux (phase, frequency, intensity, etc.). MOEM-accelerometers based on wave optics are tunnel, grating or interferometric resonators [22][23][24], Fabry-Perot resonators [25][26][27][28], photon crystals [29][30][31] and others. At present, MOEM-accelerometers based on the fiber Bragg grating (FBG) with direct integration into optical fiber are widely used [32][33][34][35].…”

Section: Introductionmentioning

confidence: 99%

An Optical Measuring Transducer for a Micro-Opto-Electro-Mechanical Micro-g Accelerometer Based on the Optical Tunneling Effect

et al. 2023

Micro-opto-electro-mechanical (MOEM) accelerometers that can measure small accelerations are attracting growing attention thanks to their considerable advantages—such as high sensitivity and immunity to electromagnetic noise—over their rivals. In this treatise, we analyze 12 schemes of MOEM-accelerometers, which include a spring mass and a tunneling-effect-based optical sensing system containing an optical directional coupler consisting of a fixed and a movable waveguide separated by an air gap. The movable waveguide can perform linear and angular movement. In addition, the waveguides can lie in single or different planes. Under acceleration, the schemes feature the following changes to the optical system: gap, coupling length, overlapping area between the movable and fixed waveguides. The schemes with altering coupling lengths feature the lowest sensitivity, yet possess a virtually unlimited dynamic range, which makes them comparable to capacitive transducers. The sensitivity of the scheme depends on the coupling length and amounts to 11.25 × 103 m−1 for a coupling length of 44 μm and 30 × 103 m−1 for a coupling length of 15 μm. The schemes with changing overlapping areas possess moderate sensitivity (1.25 × 106 m−1). The highest sensitivity (above 6.25 × 106 m−1) belongs to the schemes with an altering gap between the waveguides.