Yizheng Zhu

US Patent:

7762720, Jul 27, 2010

Filed:

Aug 8, 2007

Appl. No.:

11/835835

Inventors:

Yizheng Zhu - Durham NC, US
Anbo Wang - Blacksburg VA, US

Assignee:

Virginia Tech Intellectual Properties, Inc. - Blacksburg VA

International Classification:

G01J 5/00
G01K 11/00

US Classification:

374131, 374121, 374161

Abstract:

A method of coupling a silica fiber and a sapphire fiber includes providing a silica fiber having a doped core and a cladding layer, with the doped core having a prescribed diameter, providing a sapphire fiber having a diameter less than the doped core, placing an end of the sapphire fiber in close proximity to an end of the silica fiber, applying a heat source to the end of silica fiber and introducing the end of sapphire fiber into the heated doped core of the silica fiber to produce a coupling between the silica and sapphire fibers.

US Patent:

8508746, Aug 13, 2013

Filed:

Mar 25, 2011

Appl. No.:

13/072294

Inventors:

Adam Wax - Durham NC, US
Yizheng Zhu - Durham NC, US
Natan Tzvi Shaked - Bat Yam IL, US

Assignee:

Duke University - Durham NC

International Classification:

G01B 9/021

US Classification:

356457, 356244

Abstract:

Disclosed herein are interferometric systems having reflective chambers and related methods. According to an aspect, an interferometric system may include a light source for generating an illumination beam that propagates towards a sample. A sample holder may hold the sample and include a partially reflective cover for allowing a first portion of the illumination beam to pass therethrough to interact with the sample to produce a sample beam that propagates substantially along an optical axis. The cover may be oriented at an angle for reflecting a second portion of the illumination beam to produce a reference beam that propagates at a predetermined angle with respect to the optical axis. An imaging module may redirect the reference beam towards the optical axis at a detection plane. A detector may intercept the sample and reference beams and may generate a holographic representation of the sample based on the beams.

US Patent:

20050062979, Mar 24, 2005

Filed:

Aug 5, 2004

Appl. No.:

10/911635

Inventors:

Yizheng Zhu - Blacksburg VA, US
Xingwei Wang - Blacksburg VA, US
Juncheng Xu - Blacksburg VA, US
Anbo Wang - Blacksburg VA, US

International Classification:

G01B009/02

US Classification:

356480000

Abstract:

A fiber optic sensor has a hollow tube bonded to the endface of an optical fiber, and a diaphragm bonded to the hollow tube. The fiber endface and diaphragm comprise an etalon cavity. The length of the etalon cavity changes when applied pressure or acceleration flexes the diaphragm. The entire structure can be made of fused silica. The fiber, tube, and diaphragm can be bonded with a fusion splice. The present sensor is particularly well suited for measuring pressure or acceleration in high temperature, high pressure and corrosive environments (e.g., oil well downholes and jet engines). The present sensors are also suitable for use in biological and medical applications.

US Patent:

20130128264, May 23, 2013

Filed:

Mar 19, 2010

Appl. No.:

13/636076

Inventors:

Adam Wax - Chapel Hill NC, US
Yizheng Zhu - Blacksburg VA, US

Assignee:

DUKE UNIVERSITY - Durham NC

International Classification:

G01N 21/47

US Classification:

356300

Abstract:

Optical fiber-based angle-resolved low coherence interferometric systems and methods are disclosed for imaging of scattering samples and measurement of optical and structural properties. A single-mode collection optical fiber can be employed and scanned to collect an angular scattering distribution of scattered light from the sample. Use of a single-mode collection optical fiber can reduce cost, increase signal accuracy, and provide compatibility with optical coherence tomography systems, as examples. In certain embodiments, collected angular scatterings of light from the sample are cross-correlated with a reference signal to provide an angular scattering distribution of scattering of light from the sample. The angular scattering distribution can be spectrally dispersed to yield an angle-resolved, spectrally-resolved cross-correlation profile having depth-resolved information about the sample at the scattering angles. The angle-resolved, spectrally-resolved cross-correlation profile can be analyzed to provide size and/or depth information about the sample. The systems and methods can also be employed in non-interferometric modes.

US Patent:

20190056212, Feb 21, 2019

Filed:

Feb 3, 2017

Appl. No.:

16/075174

Inventors:

YIZHENG ZHU - BLACKSBURG VA, US

Assignee:

VIRGINIA TECH INTELLECTUAL PROPERTIES, INC. - BLACKSBURG VA

International Classification:

G01B 9/02
G01B 9/04

Abstract:

Various methods, systems and apparatus are provided for imaging and sensing using interferometry. In one example, a system includes an interferometer; a light source that can provide light to the interferometer at multiple wavelengths (λ); and optical path delay (OPD) modifying optics that can enhance contrast in an interferometer output associated with a sample. The light can be directed to the sample by optics of the interferometer. The interferometer output can be captured by a detector (e.g., a camera) at each of the multiple wavelengths (λ). In another example, an apparatus includes an add-on unit containing OPD that can enhance contrast in an interferometer output associated with a sample illuminated by light at a defined wavelength (λ). A detector can be attached to the add-on unit to record the interferometer output at the defined wavelength (λ).