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Updated: Jun 14, 2026
14:04
Detection of Protein Aggregation using Fluorescence Correlation Spectroscopy
Published on: April 25, 2021
Summary
A novel, nondestructive optical fiber preform core diameter measurement technique uses ultraviolet fluorescence. This method accurately determines core size without index matching, offering wide applicability for optical fiber production.
Area of Science:
- Optoelectronics
- Materials Science
- Optical Engineering
Background:
- Accurate measurement of optical fiber preform core diameters is crucial for single-mode fiber production.
- Existing methods often require index matching, complicating the process.
- Nondestructive techniques are preferred to preserve preform integrity.
Purpose of the Study:
- To present a new nondestructive method for measuring single-mode optical fiber preform core diameters.
- To eliminate the need for index matching the cladding during measurement.
- To theoretically analyze and experimentally validate the technique's applicability and precision.
Main Methods:
- Utilizing ultraviolet light from mercury-discharge lamps incident on the preform.
- Detecting fluorescent emission peaking at the core interface with a video camera.
- Theoretically analyzing the imaging effects of circular and elliptically distorted cladding.
Main Results:
- The developed technique accurately measures core diameters without index matching.
- Theoretical analysis shows cladding shape influences magnification and image shift.
- Experimental results agree within ~1% with other measurement techniques.
Conclusions:
- The presented method offers a precise and widely applicable approach for nondestructive core diameter measurement.
- The technique's robustness to cladding distortions enhances its practical utility.
- This method contributes to improved quality control in optical fiber preform manufacturing.
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