James Easter Howell

US Patent:

7248755, Jul 24, 2007

Filed:

Mar 31, 2004

Appl. No.:

10/543288

Inventors:

Andrew D Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Henrick Hofvander - Boulder CO, US
Bernard Patrick Masterson - Louisville CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G02B 6/00

US Classification:

385 13, 385 12

Abstract:

A sensing apparatus consisting of more than one diode laser having select lasing frequencies, a multiplexer optically coupled to the outputs of the diode lasers with the multiplexer being further optically coupled to a pitch side optical fiber. Multiplexed laser light is transmitted through the pitch side optical fiber to a pitch optic operatively associated with a process chamber which may be a combustion chamber or the boiler of a coal or gas fired power plant. The pitch optic is oriented to project multiplexed laser output through the process chamber. Also operatively oriented with the process chamber is a catch optic in optical communication with the pitch optic to receive the multiplexed laser output projected through the process chamber. The catch optic is optically coupled to an optical fiber which transmits the multiplexed laser output to a demultiplexer. The demultiplexer demultiplexes the laser light and optically couples the select lasing frequencies of light to a detector with the detector being sensitive to one of the select lasing frequencies.

US Patent:

7389027, Jun 17, 2008

Filed:

Jul 24, 2007

Appl. No.:

11/782481

Inventors:

Andrew D. Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Henrik Hofvander - Boulder CO, US
Bernard Patrick Masterson - Boulder CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G02B 6/26

US Classification:

385 39, 385 15

Abstract:

A pitch side optical system for use in diode laser spectroscopy consisting of more than one diode laser having select lasing frequencies with each diode laser being coupled to an end of a distinct input optical fiber. The pitch side optical system further consists of a multiplexer optically coupled to the other end of less than all of the input optical fibers with the multiplexer outputting multiplexed laser light to a pitch side optical fiber. The pitch side optical system further consists of a coupler optically coupled to the far end of the pitch side optical fiber and the far end of an unmultiplexed input optical fiber with the coupler combining the multiplexed laser light and the unmultiplexed laser light and outputting the combined light to a transmission optical fiber. Typically, the coupler is located near the combustion process. The pitch side optical system further consists of a pitch optic coupled to the transmission optical fiber.

US Patent:

7469092, Dec 23, 2008

Filed:

Jul 24, 2007

Appl. No.:

11/782492

Inventors:

Andrew D. Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Henrik Hofvander - Boulder CO, US
Bernard Patrick Masterson - Boulder CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G02B 6/00

US Classification:

385147, 385 52

Abstract:

A diode laser spectroscopy gas sensing apparatus having a diode laser with a select lasing frequency, a pitch optic coupled to the diode laser with the pitch optic being operatively associated with a process chamber and oriented to project laser light along a projection beam through the process chamber. This embodiment additionally includes a catch optic in optical communication with the pitch optic to receive the laser light projected through the process chamber and an optical fiber optically coupled to the catch optic. In addition, the catch optic is operatively associated with a catch side alignment mechanism which provides for the alignment of the catch optic with respect to the projection beam to increase a quantity of laser light received by the catch optic from the pitch optic and coupled to the optical fiber and a detector sensitive to the select lasing frequency optically coupled to the optical fiber. The catch side alignment mechanism may consist of means to tilt the catch optic along a first axis and a second axis orthogonal to the first axis with both the first and second axes being approximately orthogonal to the projection beam.

US Patent:

7729566, Jun 1, 2010

Filed:

Jul 24, 2007

Appl. No.:

11/782475

Inventors:

Andrew D. Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Henrik Hofvander - Boulder CO, US
Bernard Patrick Masterson - Boulder CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G02B 6/00

US Classification:

385 13, 356 51, 356 73, 385 37

Abstract:

A method of sensing a process utilizing a sensing apparatus consisting of more than one diode laser having select lasing frequencies, a multiplexer optically coupled to the outputs of the diode lasers with the multiplexer being further optically coupled to a pitch side optical fiber. Multiplexed laser light is transmitted through the pitch side optical fiber to a pitch optic operatively associated with a process chamber which may be a combustion chamber or the boiler of a coal or gas fired power plant. The pitch optic is oriented to project multiplexed laser output through the process chamber. Also operatively oriented with the process chamber is a catch optic in optical communication with the pitch optic to receive the multiplexed laser output projected through the process chamber. The catch optic is optically coupled to an optical fiber which transmits the multiplexed laser output to a demultiplexer. The demultiplexer demultiplexes the laser light and optically couples the select lasing frequencies of light to a detector with the detector being sensitive to one of the select lasing frequencies.

US Patent:

7787123, Aug 31, 2010

Filed:

Oct 4, 2006

Appl. No.:

12/067789

Inventors:

James Howell - Louisville CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G01N 21/39

US Classification:

356437, 356 51, 25033913, 250343

Abstract:

A method of calibrating an absorption spectroscopy measurement wherein the calibration method includes projecting laser light through a sample of a first quantity of a gas of interest and a second irrelevant quantity of a spectroscopically identical or similar gas (). The first and second spectroscopic absorptions of the laser light are measured over specific first and second absorption lines. A functional relationship is determined between the first and second measured spectroscopic absorptions and two unknown variables. The function relationships may then be simultaneously solved to determine one or both unknown variables and thereby obtain a measurement relating to the first quantity of the gas of interest, calibrated for the second irrelevant quantity of gas.

US Patent:

8255169, Aug 28, 2012

Filed:

May 23, 2008

Appl. No.:

12/600034

Inventors:

Henrik Hofvander - Boulder CO, US
Andrew D. Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Qingchun Zhao - Longmont CO, US

Assignee:

Zolo Technologies, Inc. - Boulder CO

International Classification:

G01N 31/00
G01R 13/00

US Classification:

702 24, 702 66, 702189, 702190

Abstract:

A method of absorption spectroscopy including obtaining absorption data at multiple wavelengths along more than one line-of-sight path through a quantity of gas of interest. The method further includes identifying more than one temperature and gas species concentration bin along the multiple line-of-sight paths and creating a map of temperature and gas species concentration. The map thus created will have at least two-dimensional information derived from select temperature and gas species concentration bins identified along more than one line-of-sight path. Apparatus for implementing the above method is also disclosed.

US Patent:

20070263956, Nov 15, 2007

Filed:

Jul 24, 2007

Appl. No.:

11/782483

Inventors:

Andrew Sappey - Lakewood CO, US
James Howell - Louisville CO, US
Henrik Hofvander - Boulder CO, US
Bernard Masterson - Boulder CO, US

Assignee:

ZOLO TECHNOLOGIES, INC. - Boulder CO

International Classification:

G02B 6/00

US Classification:

385013000

Abstract:

A catch side optical system for use in diode laser spectroscopy consisting of a catch side optic optically coupled to a catch side multimode optical fiber and means to mechanically manipulate a section of the catch side multimode optical fiber to minimize catch side mode noise. The mechanical manipulation may consist of twisting the catch side multimode optical fiber around its longitudinal axis. The means to mechanically manipulate the section of the catch side multimode optical fiber in the above fashion may consist of a motor associated with the catch side multimode optical fiber such that a section of fiber is held fast relative to a shaft position of the motor and the motor shaft is repetitively swept through +360 degrees and −360 degrees of motion. The frequency of the motor shaft sweep may be at least 10 Hz to enable effective averaging of the transmitted signal and thereby reduce the effect of catch side mode noise.

US Patent:

20120140234, Jun 7, 2012

Filed:

Aug 10, 2010

Appl. No.:

13/389902

Inventors:

Bernard Patrick Masterson - Louisville CO, US
James Howell - Louisville CO, US
Henrik Hofvander - Boulder CO, US
Andrew D. Sappey - Lakewood CO, US

Assignee:

ZOLO TECHNOLOGIES, INC. - Boulder CO

International Classification:

G01N 21/55

US Classification:

356445

Abstract:

An apparatus and methods for measuring combustion parameters in the measurement zone of a gas turbine engine. The measurement zone is defined as being between an outer casing and an engine component having a reflecting surface inside the outer casing. The apparatus comprises a laser generating a transmitting beam of light of a select wavelength and a multimode transmitting fiber optically coupled to the laser. A transmitting optic is optically coupled to the multimode optical fiber for transmitting the beam into the measurement zone. The reflecting surface is configured to provide a Lambertian reflection. A receiving optic is positioned to receive the Lambertian reflection. Means are provided in operative association with the multimode transmitting fiber for averaging modal noise induced signal level variation of light propagating within the multimode transmitting fiber.