Philip A Rogers

US Patent:

7206064, Apr 17, 2007

Filed:

Feb 28, 2006

Appl. No.:

11/362725

Inventors:

Philip L. Rogers - Potomac MD, US
Kerry J. Vahala - San Gabriel CA, US

Assignee:

Optical Air Data Systems, LLC - Manassas VA

International Classification:

G01P 3/36

US Classification:

356 28, 356 285

Abstract:

A laser Doppler velocimeter is formed using erbium-doped fiber as the lasing medium. The fiber is diode-pumped. By properly modulating the lasing in the fiber, pulses of radiation may be generated. A telescope acts as the transmission device to focus the radiation at a specified point, and may also act as the receiving system for reflected radiation. The portion of the reflected radiation collected by the receiving system is analyzed to determine the Doppler shift caused by aerosols or objects at the focal point of the telescope.

US Patent:

7505119, Mar 17, 2009

Filed:

Apr 13, 2001

Appl. No.:

10/257289

Inventors:

Philip L Rogers - Manassas VA, US

Assignee:

Optical Air Data Systems, LLC - Manassas VA

International Classification:

G01C 3/06
F41G 3/26

US Classification:

356 401, 434 22, 434 27

Abstract:

An optical system or assembly is formed of a plurality of optical sources () and components of different laser-based equipment systems. The sources and/or components may be combined and/or eliminated to reduce complexity, cost and/or overall weight of the system by consolidating multiple laser sources into a reduced number of sources, and by multiplexing () different wavelength signals over common carriers. A laser engagement system () and an infrared aim light () (or infrared illuminator) are powered by a single laser source which is adopted for use with conventional equipment by lengthening the duration of the coded pulses emitted by the transmitter. The transmitter may be triggered in response to the heat and/or pressure generated by the blank upon firing. A visible bore light may be eliminated by connecting infrared and/or visible aim light () directly to a rifle barrel. The laser engagement system and the infrared aim light (or infrared illuminator) are provided in a common housing assembly ().

US Patent:

20040156035, Aug 12, 2004

Filed:

Feb 5, 2004

Appl. No.:

10/771310

Inventors:

Philip Rogers - Manassas VA, US

International Classification:

G01P003/36

US Classification:

356/028500

Abstract:

The disclosed invention concept utilizes a homodyne/heterodyne interferometer technique in a modified lidar in such a manner as to sense the rotational velocity magnitude and sense of a rotating (or “spinning”) object. Sensing is accomplished in assessing either the Doppler bandwidth of a single axis system. or in sensing the frequency separation of Doppler spectrums in a “two” axis system. The technique is unique in that the Doppler bandwidth is linearly proportional to rotational velocity and independent of intercept position in the rotation plane. The technique as disclosed is based on optical fiber lidar techniques, but can be implemented in free-space optics as well. The disclosed invention therefore comprises both a technique for utilization of an optical fiber lidar and a new arrangement of lidar elements. Compact and cost effective, standoff rotation velocity sensors and systems can be fabricated with this technique.

US Patent:

20050083513, Apr 21, 2005

Filed:

Oct 22, 2004

Appl. No.:

10/969964

Inventors:

Philip Rogers - Manassas VA, US

International Classification:

G01P003/36

US Classification:

356028000

Abstract:

A method of generating in-quadrature signals is disclosed. The method comprises phase shifting a Doppler frequency-shifted signal; phase shifting a local oscillator signal; mixing the phase shifted Doppler frequency-shifted signal and the phase-shifted local oscillator signal generating thereby a signal which includes the phase-shifted Doppler frequency-shifted signal and a further phase-shifted local oscillator signal; and mixing the unphase-shifted Doppler frequency-shifted signal and the unphase-shifted local oscillator signal generating thereby a signal which includes the unphase-shifted local oscillator signal and a further phase-shifted Doppler frequency-shifted signal. A method of determining the velocity of an object is also disclosed. The method comprises receiving a Doppler frequency-shifted signal reflected of backscattered from the object; generating a local oscillator signal; based upon the received Doppler frequency-shifted signal and the local oscillator signal, generating an in-phase signal; based upon the received Doppler frequency-shifted signal and the local oscillator signal generating an in-quadrature signal; summing the in-phase signal and the in-quadrature signal; and transforming the summation of the in-phase signal and the in-quadrature signal. A lidar is disclosed comprising an optical system for transmitting an output signal to an object and receiving thereby a Doppler frequency-shifted signal reflected or backscattered from the object; a signal mixing assembly receptive of the Doppler frequency-shifted signal and a local oscillator signal generating thereby an in-phase signal and an in-quadrature signal; and a signal transformer for transforming the in-phase signal and an in-quadrature signals. A signal mixing system is disclosed comprising an array of signal couplers receptive of a Doppler frequency-shifted signal and a local oscillator signal generating thereby an in-phase signal which includes the unphase-shifted local oscillator signal and a phase-shifted Doppler frequency-shifted signal and an in-quadrature signal which includes the phase-shifted Doppler frequency-shifted signal and a further phase-shifted local oscillator signal; and a plurality of signal detectors receptive of the in-phase and in-quadrature signals.

US Patent:

20080024756, Jan 31, 2008

Filed:

Jul 31, 2007

Appl. No.:

11/882280

Inventors:

Philip Rogers - Manassas VA, US

International Classification:

G01S 17/00
G01P 3/36
G01S 17/42
G01S 17/58

US Classification:

356005090, 356028500

Abstract:

A method of generating in-quadrature signals is disclosed. The method comprises phase shifting a Doppler frequency-shifted signal; phase shifting a local oscillator signal; mixing the phase shifted Doppler frequency-shifted signal and the phase-shifted local oscillator signal generating thereby a signal which includes the phase-shifted Doppler frequency-shifted signal and a further phase-shifted local oscillator signal; and mixing the unphase-shifted Doppler frequency-shifted signal and the unphase-shifted local oscillator signal generating thereby a signal which includes the unphase-shifted local oscillator signal and a further phase-shifted Doppler frequency-shifted signal. A method of determining the velocity of an object is also disclosed. The method comprises receiving a Doppler frequency-shifted signal reflected of backscattered from the object; generating a local oscillator signal; based upon the received Doppler frequency-shifted signal and the local oscillator signal, generating an in-phase signal; based upon the received Doppler frequency-shifted signal and the local oscillator signal generating an in-quadrature signal; summing the in-phase signal and the in-quadrature signal; and transforming the summation of the in-phase signal and the in-quadrature signal. A lidar is disclosed comprising an optical system for transmitting an output signal to an object and receiving thereby a Doppler frequency-shifted signal reflected or backscattered from the object; a signal mixing assembly receptive of the Doppler frequency-shifted signal and a local oscillator signal generating thereby an in-phase signal and an in-quadrature signal; and a signal transformer for transforming the in-phase signal and an in-quadrature signals. A signal mixing system is disclosed comprising an array of signal couplers receptive of a Doppler frequency-shifted signal and a local oscillator signal generating thereby an in-phase signal which includes the unphase-shifted local oscillator signal and a phase-shifted Doppler frequency-shifted signal and an in-quadrature signal which includes the phase-shifted Doppler frequency-shifted signal and a further phase-shifted local oscillator signal; and a plurality of signal detectors receptive of the in-phase and in-quadrature signals.

US Patent:

20080170235, Jul 17, 2008

Filed:

Mar 12, 2007

Appl. No.:

11/716654

Inventors:

Philip L. Rogers - Potomac MD, US
Kerry J. Vahala - San Gabriel CA, US

International Classification:

G01B 9/02
G01N 21/47
G01W 1/00

US Classification:

356521, 356446, 7317016

Abstract:

A laser Doppler velocimeter is formed using erbium-doped fiber as the lasing medium. The fiber is diode-pumped. By properly modulating the lasing in the fiber, pulses of radiation may be generated. A telescope acts as the transmission device to focus the radiation at a specified point, and may also act as the receiving system for reflected radiation. The portion of the reflected radiation collected by the receiving system is analyzed to determine the Doppler shift caused by aerosols or objects at the focal point of the telescope.

US Patent:

20130044309, Feb 21, 2013

Filed:

Feb 14, 2012

Appl. No.:

13/396313

Inventors:

Elizabeth A. DAKIN - Great Falls VA, US
Priyavadan MAMIDIPUDI - Bristow VA, US
Philip L. ROGERS - Hume VA, US
Rupak CHANGKAKOTI - Haymarket VA, US
Daniel C. DAKIN - Great Falls VA, US

Assignee:

Optical Air Data Systems, LLC - Manassas VA

International Classification:

G01C 3/08

US Classification:

356 409

Abstract:

An all fiber optic laser based scanning system for real time terrain mapping under degraded visual conditions is disclosed. A laser output is modulated to achieve a desired pulse width and pulse repetition frequency (PRF) and the modulated signal is amplified. The amplified optical signals are split into N channels that correspond to N elements of an optically phased array that steers light by modulating the phase of light entering and exiting the optical system. By applying a linear phase shift across the beam's wave front, the light propagating along the system's optical axis is steered to an off-axis angle. A real time map of an underlying terrain is accomplished by sweeping the N channel array across the terrain while collecting range information from each scan grid.

US Patent:

20130162974, Jun 27, 2013

Filed:

May 22, 2012

Appl. No.:

13/478025

Inventors:

Elizabeth A. Dakin - Great Falls VA, US
Priyavadan Mamidipudi - Bristow VA, US
Philip L. Rogers - Hume VA, US
Daniel C. Dakin - Great Falls VA, US

Assignee:

Optical Air Data Systems, LLC - Manassas VA

International Classification:

G01N 21/53
G01P 5/26

US Classification:

356 28, 356338, 356 72

Abstract:

Systems and methods for laser based measurement of air parameters for use, e.g., on aircraft are disclosed. An example system includes a coherent source of radiation, a modulator, a transceiver, an optical mixer, and a measuring system. The coherent source produces a coherent radiation beam, and the modulator is configured to modulate the coherent radiation beam. The transceiver is configured to transmit the modulated radiation beam to, and receive a scattered radiation signal from a target region. The optical mixer is configured to determine a difference between the scattered radiation signal and the reference radiation beam. The measuring system is configured to determine at least one of velocity, air density, pressure, temperature, barometric altitude, angle of attack, angle of side slip, icing and turbulence based on the difference between the scattered radiation signal and the reference radiation beam.