Masters Theses


"This research is a study conducted on the excitation of whispering gallery modes (WGM) in small micron-scale glass spheres. Optical WGM may be represented by a light wave that propagates along the surface of the sphere and reaches back itself in phase at specific wavelengths. Due to this, very high intensities of light with narrow line widths circulate in the microspheres contributing to high Q factor. The evanescent field of an optical waveguide is used to resonantly stimulate the WGM.

The WGM excitation in fused silica spheres was demonstrated in the laboratory with 60% coupling efficiency. Tapered optical fibers were initially used as the coupling mechanism. The long period fiber grating (LPFG) is suggested as an alternate coupling mechanism. The problems in using LPFG with fused silica spheres were theoretically and experimentally verified.

This principle was also applied to characterize the optical losses in high refractive index beads. The glass beads exhibit enhanced IR retro-reflectivity which fins application in IR tagging and identification. This thesis provides a detailed study of all these aspects with relevant experimental data to support them"--Abstract, page iii.


Xiao, Hai, Dr.

Committee Member(s)

Tsai, Hai-Lung
Watkins, Steve Eugene, 1960-


Electrical and Computer Engineering

Degree Name

M.S. in Electrical Engineering


Missouri University of Science and Technology

Publication Date

Spring 2010


viii, 68 pages

Note about bibliography

Includes bibliographical references (pages 64-67).


© 2010 Sudha Sneha Devarakonda, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Electric circuit analysis
Microelectromechanical systems
Optical resonance

Thesis Number

T 9606

Print OCLC #


Electronic OCLC #


Link to Catalog Record

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