Measurement of fiber diameters with high precision
December 31, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMethod for measuring the parameters of optical fibers Method and apparatus for determining ratio of core radius to cladding radius in clad optical fibers Monitoring and control of optical fiber diameters Method for measuring the parameters of optical fibers Method and apparatus for detection of inclusions in glass article or the like Methods and apparatus for improving the resolution of measured parameters System for measuring optical waveguide fiber diameter Method of observing the core region of optical fibers and preforms Manufacture of concentric coatings for fiber waveguides Method for testing specimens InventorsAssigneeApplicationNo. 816882 filed on 12/31/1991US Classes:356/496, For dimensional measurement356/73.1, FOR OPTICAL FIBER OR WAVEGUIDE INSPECTION356/503, Thickness356/635Width or diameterExaminersPrimary: Turner, Samuel A.Attorney, Agent or FirmInternational ClassG01B 009/02AbstractMethods for measuring the diameters of transparent filaments with high precision, e.g., RMS standard deviations of less than 0.02 microns, are provided. The methods involve determining the average spatial frequency ω of the far-field interference pattern produced by illuminating the filament with a beam of laser light. The average spatial frequency is determined by performing a fast Fourier transform (FFT) on the interference data to obtain a coarse estimate for the average and then performing a set of discrete sequence Fourier transforms (DSFTs) in the region of the coarse estimate to obtain the desired high precision estimate of the average. Efficient on-line processing procedures are provided so that real time measurements can be performed on, for example, a moving optical waveguide fiber, at rates of 500 measurements/second and above.Other References
Field of SearchFOR OPTICAL FIBER OR WAVEGUIDE INSPECTION | |
