Rigid and flexible multimode fiber endoscopes
Abstract/Contents
- Abstract
- Endoscopes are medical instruments that transmit images through long, thin optical conduits. An endoscope built using a single multimode optical fiber (MMF) as the optical conduit has roughly two orders of magnitude better spatial resolution than current, commercial endoscopes built using fiber bundles. Despite the potential of MMF endoscopes, research is necessary to improve the signal-to-noise ratio (SNR), imaging time, field of view, and flexibility before they can become a practical technology. Chapters 2 and 3 describe and experimentally demonstrate a complete method of imaging through a rigid MMF endoscope. The advantages of this method are that arbitrary sampling patterns can be used to sample the object to be imaged, and spatial resolution is increased by a factor of 4 over comparable MMF imaging methods. In this method, a sequence of random field patterns is input to the MMF, generating a sequence of random intensity patterns at the output, which are used to sample an object; reflected power values are returned through the MMF, and linear optimization is used to reconstruct an image using a method we term optimization-based reconstruction. The point-spread function and noise performance under different SNR and noise regimes are mathematically derived. Chapters 4 and 5 describe and present experimental results for a complete method of imaging through a flexible MMF endoscope. This is achieved by the addition of a partial reflector to the distal end of the MMF, which allows measurement of the mode coupling of the transmitted light through the MMF using the reflected light arriving back at the proximal end of the MMF. We simulate imaging through such a flexible MMF endoscope with 1588 spatial modes and show that an image can be obtained even after the MMF is arbitrarily bent. We experimentally verify the first part of this method by finding that the perturbation of the light reflected from the partial reflector is indeed highly correlated with the perturbation of the light transmitted through the MMF, and use it to form spots at the distal end of a flexible MMF with quality 10-15% higher than if the perturbation of the MMF is ignored.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2017 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | Gu, Ruo Yu |
|---|---|
| Associated with | Stanford University, Department of Electrical Engineering. |
| Primary advisor | Kahn, Joseph M |
| Thesis advisor | Kahn, Joseph M |
| Thesis advisor | Fan, Shanhui, 1972- |
| Thesis advisor | Miller, D. A. B |
| Advisor | Fan, Shanhui, 1972- |
| Advisor | Miller, D. A. B |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Ruo Yu Gu. |
|---|---|
| Note | Submitted to the Department of Electrical Engineering. |
| Thesis | Thesis (Ph.D.)--Stanford University, 2017. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2017 by Ruo Yu Gu
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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