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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A confocal Fabry-Perot interferometer for use in LIDAR receivers

Neal, Kerry Ann. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Kevin S. Repasky. Includes bibliographical references (leaves 61-62).
22

A virtual RSNS direction finding antenna system /

Chen, Jui-Chun. January 2004 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, Dec. 2004. / Thesis Advisor(s): David C. Jenn, Phillip E. Pace. Includes bibliographical references (p. 69-70). Also available online.
23

Quantum precision sensing

Santos, Marcílio Manuel dos January 2014 (has links)
No description available.
24

A long baseline optical interferometer for astrometry.

Shao, Michael January 1978 (has links)
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Physics. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / Ph.D.
25

Stress holographic interferometry.

Kalousek, Joseph. January 1971 (has links)
No description available.
26

Conversion of laser phase noise to amplitude noise in a Lummer-Gehrcke interferometer and in oxygen gas

Wichner, Brian D. 16 June 1998 (has links)
In order to observe laser phase noise, this noise must be converted to amplitude noise, which can be achieved using either an interferometer or an absorption resonance in an atomic/molecular vapor or gas. When phase noise is converted to amplitude noise, it is manifested as a heterodyne signal in the output of an optical square-law detector. Thus, phase noise is measured by optical heterodyne spectroscopy, or, equivalently, laser phase noise spectroscopy. In recent work on diode laser noise spectroscopy of rubidium and oxygen, the observed spectroscopic lineshapes were not in total agreement with theoretical predictions. We have repeated the previous work on the oxygen A-band transitions, and we now find qualitative agreement with theory. In addition, we have measured the diode laser noise spectrum of a Lummer- Gehrcke interferometer (LGI), comparing the heterodyne lineshape of a LGI transmission spectrum with a qualitative theory that we develop in this thesis. A theory, from other workers, predicts the intensity fluctuations from a Doppler-broadened, two-level atomic/molecular system driven with a phase-diffusing laser field. We show that a simplified version of this theory, which ignores Doppler effects of the system, is a useful approximation to the complete theory, by comparing computer-generated heterodyne lineshapes of each, for a rubidium transition. We apply this approximate theory to an oxygen A-band transition, and compare these results with our experimental measurements. For the experimental arrangement used in the present work, diode laser noise spectroscopy may also include effects of selective reflection, which is dealt with experimentally and theoretically. Diode laser phase noise has practical importance in optical communications and atomic clocks. / Graduation date: 1999
27

The three-grating optical interferometer used as a monitoring and stabilization device for an atomic interferometer

Lopez, Peggy A. 19 February 1997 (has links)
The three-grating optical interferometer is studied to identify restrictions on alignment and improve stability. A description of the way a three-grating interferometer works is given as well as a method for proper set up. The overall power loss through the three gratings is measured and can be used to estimate the amount of atoms that will be detected at the output of the atomic interferometer. Criteria are developed for misalignment affects. Equations are presented for spacing and rotation limitations which can then be applied to the atomic interferometer. A stabilization technique is developed using a servo system. The elimination of low frequency inertial noise is accomplished. / Graduation date: 1997
28

Miniaturized Diffraction Based Interferometric Distance Measurement Sensor

Kim, Byungki 09 July 2004 (has links)
In this thesis, new metrology hardware is designed, fabricated, and tested to provide improvements over current MEMS metrology. The metrology system is a micromachined scanning interferometer having a sub-nm resolution in a compact design. The proposed microinterferometer forms a phase sensitive diffraction grating with interferometric sensitivity, while adding the capability of better lateral resolution by focusing the laser to a smaller spot size. A detailed diffraction model of the microinterferometer was developed to simulate the device performance and to suggest the location of photo detectors for integrated optoelectronics. A particular device is fabricated on a fused silica substrate using aluminum to form the deformable diffraction grating fingers and AZ P4620 photo resist (PR) for the microlens. The details of the fabrication processes are presented. The structure also enables optoelectronics to be integrated so that the interferometer with photo detectors can fit in an area that is 1mm x 1mm. The scanning results using a fixed grating micromachined scanning interferometer demonstrated that it could measure vibration profile as well as static vertical(less than a half wave length) and lateral dimension of MEMS. The SI, which is integrated with photo diodes, demonstrated its operation by scanning a cMUT. The PID control has been tested and resulted in improvement in scanned images. The integrated micromachined scanning interferometer demonstrated that the deformable grating could be used to tune the measurement keep the interferometer in quadrature for highest sensitivity.
29

Design and development of a portable Moiré interferometer

Ramasubramanian, Srikanth, January 2004 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains x, 132 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 131).
30

Biomedical applications of a fiber based low-coherence interferometer for quantitative differential phase measurements

Akkin, Taner, Milner, Thomas E., Rylander, H. Grady, January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisors: Thomas E. Milner and H. Grady Rylander III. Vita. Includes bibliographical references. Available also from UMI Company.

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