We present a compact heterodyne laser interferometer developed for high-sensitivity displacement sensing applications. This interferometer consists of customized prisms and wave plates assembled as a quasi-monolithic unit to realize a miniaturized system. The interferometer design adopts a common-mode rejection scheme to provide a high rejection ratio to common environmental noise. Experimental tests in vacuum show a displacement sensitivity level of at and as low as above . The prototype unit is in size and weighs , allowing subsequent integration in compact systems.
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Optomechanical inertial sensors
We present a performance analysis of compact monolithic optomechanical inertial sensors that describes their key fundamental limits and overall acceleration noise floor. Performance simulations for low-frequency gravity-sensitive inertial sensors show attainable acceleration noise floors on the order of . Furthermore, from our performance models, we devised an optimization approach for our sensor designs, sensitivity, and bandwidth trade space. We conducted characterization measurements of these compact mechanical resonators, demonstrating -products at levels of 250 kg, which highlight their exquisite acceleration sensitivity.
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- PAR ID:
- 10165375
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 59
- Issue:
- 22
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. G167
- Size(s):
- Article No. G167
- Sponsoring Org:
- National Science Foundation
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