Charles A Marshall

US Patent:

6819762, Nov 16, 2004

Filed:

Sep 10, 2001

Appl. No.:

09/950285

Inventors:

Andrew R. Jones - Roslindale MA
Andrew G. Ziegler - Arlington MA
Charles M. Marshall - North Andover MA
Timothy E. White - Acton MA

Assignee:

Aura Communications, Inc. - Wilmington MA

International Classification:

H04M 100

US Classification:

379430, 381380

Abstract:

An ear mounted speaker assembly provides improved internal and external stability of a âin-the-earâ headset. A housing containing a speaker further contains an extender, audio portion and electrical compartment. The extender is adapted to rest in the intertragic notch of the ear. The audio portion is mounted to the extender and is of greater width than the extender. The audio portion is adapted to be positioned within the lower concha behind the tragus and antitragus of the ear. The compressible retainer extends from the surface of the housing and presses against the upper concha of the ear. The strut extends from the lower surface of the housing below the extender and extends downward outside the intertragic notch and presses against skin to stabilize the speaker assembly within the ear. Compressible retainers may be interchangeable and may come in a kit containing a plurality of interchangeable compressible retainers of a variety of shapes.

US Patent:

7522328, Apr 21, 2009

Filed:

May 11, 2007

Appl. No.:

11/803044

Inventors:

Matthias Wagner - Cambridge MA, US
Shuyun Wu - Acton MA, US
Charles M. Marshall - North Andover MA, US
Eugene Y. Ma - Newton MA, US
John F. Heanue - Manchester MA, US

Assignee:

Redshift Systems Corporation - Burlington MA

International Classification:

G02B 26/00
G02B 27/00

US Classification:

359237, 359578

Abstract:

An apparatus includes a thin-film interference filter structure having a generally wavelength-dependent resonant response to incident optical energy in a predetermined range of wavelengths. The thin-film interference filter structure includes a thermally tunable layer having a thermally tunable optical characteristic such that a range of wavelength-dependent resonant optical responses of the thermally tunable layer are induced by a corresponding range of thermal conditions of the thermally tunable layer. The thin-film interference filter structure is configured to (1) receive a spatially varying pattern of thermal energy at the thermally tunable layer to impart a corresponding spatially varying pattern to the thermally tunable characteristic of the thermally tunable layer, and (2) receive the incident optical energy into the thermally tunable layer and output optical energy having spatial modulation corresponding to the spatially varying pattern of the thermally tunable characteristic.

US Patent:

7697192, Apr 13, 2010

Filed:

Apr 2, 2009

Appl. No.:

12/417430

Inventors:

Matthias Wagner - Cambridge MA, US
Shuyun Wu - Acton MA, US
Charles M. Marshall - North Andover MA, US
Eugene Y. Ma - Newton MA, US
John F. Heanue - Manchester MA, US

Assignee:

Redshift Systems Corporation - Burlington MA

International Classification:

G02F 1/01
G02B 27/00

US Classification:

359288, 359240, 359578

Abstract:

A thin-film interference filter structure has a generally wavelength-dependent resonant response to incident optical energy in a predetermined range of wavelengths. The thin-film interference filter structure includes a thermally tunable layer having a thermally tunable optical characteristic such that a range of wavelength-dependent resonant optical responses of the thermally tunable layer are induced by a corresponding range of thermal conditions of the thermally tunable layer. The thin-film interference filter structure is configured to (1) receive a spatially varying pattern of thermal energy at the thermally tunable layer to impart a corresponding spatially varying pattern to the thermally tunable characteristic of the thermally tunable layer, and (2) receive the incident optical energy into the thermally tunable layer and output optical energy having spatial modulation corresponding to the spatially varying pattern of the thermally tunable characteristic.

US Patent:

20120294321, Nov 22, 2012

Filed:

May 16, 2012

Appl. No.:

13/473256

Inventors:

Eugene Yi-Shan Ma - Newton MA, US
Charles M. Marshall - North Andover MA, US

Assignee:

REDSHIFT SYSTEMS CORPORATION - Burlington MA

International Classification:

H01S 3/10

US Classification:

372 20

Abstract:

A tunable laser has a solid state laser medium having an optical gain region and generates coherent radiation through a facet. A lens collects the coherent radiation and generates a collimated light beam. Components of an external cavity include a reflective surface and an optical filter, the reflective surface reflecting the collimated beam back to the lens and the laser medium, the optical filter positioned between the reflective surface and the lens and having two surfaces with a thermally tunable optical transmission band within the optical gain region of the laser medium. The optical filter () transmits a predominant portion of the collimated beam at a desired wavelength of operation, and () specularly reflects a remaining portion of the collimated beam from each surface, the collimated beam being incident on the optical filter such that the reflected collimated beams propagate at a non-zero angle with respect to the incident collimated beam.