Jerry Fang Chen

US Patent:

6996345, Feb 7, 2006

Filed:

May 10, 2002

Appl. No.:

10/145616

Inventors:

Jerry C. Chen - Arlington MA, US

Assignee:

The United States of America as represented by the Secretary of the Air Force - Washington DC

International Classification:

H04B 10/04

US Classification:

398183, 398186

Abstract:

Changing the phrases when mixing of optical modes gives rise to intensity effects. This occurs in multi-mode interferometer (MMI) or arrayed waveguide gratings (AWG). Here we use an electro-arefractive modulator, with a quadratic electro-optic effect that has an optical transfer function (Or power vs voltage (L-V) curve) given by is P=P(1+γ cos θ)/2 where asymmetry factor γ measures the extinction ratio and the phase difference θ between arms is In turn, the voltage V is expressed as a sum of the DC bias and RF drive V=V+V.

US Patent:

7127172, Oct 24, 2006

Filed:

Jun 2, 1999

Appl. No.:

09/324253

Inventors:

Jerry C Chen - Arlington MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H04J 14/02

US Classification:

398 85, 359723, 359885

Abstract:

The present invention relates to an optical signal shaping device such as an optical filter having a profile such that transmission of light through the device varies as a function of frequency over a selected bandwidth. The optical signal shaping device of the present invention includes a frequency dependent disperser that disperses the input optical signal to form a dispersed signal having a plurality of frequencies, a frequency selective modulator that modulates at least one of the plurality of frequencies and a frequency dependent combiner that combines the frequencies to form a modulated output signal.

US Patent:

H002190, Jun 5, 2007

Filed:

Jun 11, 2002

Appl. No.:

10/165939

Inventors:

Jerry Chen - Arlington MA, US

Assignee:

The United States of America as represented by the Secretary of the Air Force - Washington DC

International Classification:

H04B 10/12

US Classification:

398189, 398191, 375353

Abstract:

Analog information is modulated onto a high repetition rate optical pulse stream. This modulated pulse stream is transmitted over optical medium, such as long distances of fiber, and is then detected. The pulses are removed leaving only the original analog signals. The sampled encoding onto pulses allows transmission of very broad band signals and mitigates the deleterious effects of self phase modulation, dispersion and Stimulated Brillouin Scattering.

US Patent:

7400792, Jul 15, 2008

Filed:

Dec 9, 2004

Appl. No.:

11/008735

Inventors:

Jerry C. Chen - Lexington MA, US

Assignee:

Tellabs Operations, Inc. - Naperville IL

International Classification:

G02B 6/26
G02B 26/08

US Classification:

385 18, 385 39, 359196, 359223, 359226

Abstract:

A method for cross connecting optical signals includes using a common beam steerer to direct a set of optical signals from a set of input ports to a set of output ports. The method further includes adjusting a curvature of the common beam steerer so that paths of the optical signals have substantially the same effective path length.

US Patent:

7564567, Jul 21, 2009

Filed:

Jan 25, 2007

Appl. No.:

11/626966

Inventors:

Jerry C. Chen - Lexington MA, US
Sumanth Kaushik - Belmont MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G01B 11/02

US Classification:

356502

Abstract:

Described are a sensor and a method for measuring a vibration of a surface obscured from view. The sensor includes a narrowband source of a terahertz beam, a beamsplitter, a beam combiner and a terahertz detector. The beamsplitter splits the terahertz beam into a sample beam for irradiating the surface and a reference beam. The beam combiner combines the sample beam scattered from the surface and the reference beam. The terahertz detector generates an electrical signal based on a modulation of the power of the combined beams due to the vibrating surface. The electrical signal indicates a characteristic of the surface vibration. Homodyne or heterodyne detection can be utilized. Advantageously, the sensor can see surfaces that are covered, concealed or otherwise obscured behind optically opaque materials, including plastic, cloth, foam, paper and other materials. Thus the sensor has a wide variety of applications where conventional vibrometers are not practical.

US Patent:

7623744, Nov 24, 2009

Filed:

Jun 11, 2008

Appl. No.:

12/137023

Inventors:

Jerry C. Chen - Lexington MA, US

Assignee:

Tellabs Operations, Inc. - Naperville IL

International Classification:

G02B 6/26
G02B 6/32

US Classification:

385 18, 385 16, 385 17, 385 31, 385 33, 385 39

Abstract:

A method for cross connecting optical signals includes using a common beam steerer to direct a set of optical signals from a set of input ports to a set of output ports. The method further includes adjusting a curvature of the common beam steerer so that paths of the optical signals have substantially the same effective path length.

US Patent:

8270785, Sep 18, 2012

Filed:

Oct 14, 2009

Appl. No.:

12/579108

Inventors:

Jerry C. Chen - Lexington MA, US

Assignee:

Tellabs Operations, Inc. - Naperville IL

International Classification:

G02B 6/42
G02B 6/32

US Classification:

385 17, 385 16, 385 18, 385 33, 385 39

Abstract:

A method for cross connecting optical signals includes using a common beam steerer to direct a set of optical signals from a set of input ports to a set of output ports. The method further includes adjusting a curvature of the common beam steerer so that paths of the optical signals have substantially the same effective path length.

US Patent:

8514393, Aug 20, 2013

Filed:

Jan 28, 2011

Appl. No.:

13/016143

Inventors:

Mohammad Jalal Khan - Woburn MA, US
Jerry C. Chen - Lexington MA, US
Sumanth Kaushik - Belmont MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G01J 3/28

US Classification:

356326

Abstract:

Disclosed herein are a system and corresponding method for sensing terahertz radiation. The system collects terahertz radiation scattered from a target and upconverts the collected radiation to optical frequencies. A frequency-domain spectrometer senses spectral components of the upconverted signal in parallel to produce a spectroscopic measurement of the entire band of interest in a single shot. Because the sensing system can do single-shot measurements, it can sense moving targets, unlike sensing systems that use serial detection, which can only be used to sense stationary objects. As a result, the sensing systems and methods disclosed herein may be used for real-time imaging, including detection of concealed weapons, medical imaging, and hyperspectral imaging.