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We have developed a novel microscopic analysis system that combines the functions of light-sheet fluorescence microscopy (LSM) and dynamic mechanical analysis (DMA). We have integrated the three uniquely designed components of (i) a MEMS dynamic compression device with a μ-force sensor, (ii) a high-speed 3D light-sheet scanner and an imager, and (iii) a custom-programmed image-based 3D modeling algorithm. Here, we demonstrate spatially-resolved mechanical characterization of viscoelastic materials under high-resolution 3D fluorescence microscopy for the first time.
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2D Au-Coated Resonant MEMS Scanner for NIR Fluorescence Intraoperative Confocal Microscope
The electrostatic MEMS scanner plays an important role in the miniaturization of the microscopic imaging system. We have developed a new two-dimensional (2D) parametrically-resonant MEMS scanner with patterned Au coating (>90% reflectivity at an NIR 785-nm wavelength), for a near-infrared (NIR) fluorescence intraoperative confocal microscopic imaging system with a compact form factor. A silicon-on-insulator (SOI)-wafer based dicing-free microfabrication process has been developed for mass-production with high yield. Based on an in-plane comb-drive configuration, the resonant MEMS scanner performs 2D Lissajous pattern scanning with a large mechanical scanning angle (MSA, ±4°) on each axis at low driving voltage (36 V). A large field-of-view (FOV) has been achieved by using a post-objective scanning architecture of the confocal microscope. We have integrated the new MEMS scanner into a custom-made NIR fluorescence intraoperative confocal microscope with an outer diameter of 5.5 mm at its distal-end. Axial scanning has been achieved by using a piezoelectric actuator-based driving mechanism. We have successfully demonstrated ex vivo 2D imaging on human tissue specimens with up to five frames/s. The 2D resonant MEMS scanner can potentially be utilized for many applications, including multiphoton microendoscopy and wide-field endoscopy.
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- Award ID(s):
- 1808436
- PAR ID:
- 10107456
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 10
- Issue:
- 5
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/mi10050295
