Kenneth P Brewer

US Patent:

6548869, Apr 15, 2003

Filed:

Jul 13, 2001

Appl. No.:

09/905294

Inventors:

Kenneth P. Brewer - Mountain View CA
Howard D. Bartlow - Nampa ID
Johan A. Darmawan - Santa Clara CA

Assignee:

Cree Microwave, Inc. - Sunnyvale CA

International Classification:

H02H 900

US Classification:

257355, 257356, 257296

Abstract:

An RF power device comprising a power transistor fabricated in a first semiconductor chip and a MOSCAP type structure fabricated in a second semiconductor chip. A voltage limiting device is provided for protecting the power transistor from input voltage spikes and is preferably fabricated in the semiconductor chip along with the MOSCAP. Alternatively, the voltage limiting device can be a discrete element fabricated on or adjacent to the capacitor semiconductor chip. By removing the voltage limiting device from the power transistor chip, fabrication and testing of the voltage limiting device is enhanced, and semiconductor area for the power device is increased and aids in flexibility of device fabrication.

US Patent:

8473239, Jun 25, 2013

Filed:

Apr 14, 2010

Appl. No.:

12/760327

Inventors:

Donald F. Specht - Los Altos CA, US
Kenneth D. Brewer - Santa Clara CA, US
David M. Smith - Lodi CA, US
Sharon L. Adam - San Jose CA, US
John P. Lunsford - Los Altos Hills CA, US

Assignee:

Maui Imaging, Inc. - Sunnyvale CA

International Classification:

G01N 29/00

US Classification:

702100

Abstract:

Increasing the effective aperture of an ultrasound imaging probe by including more than one probe head and using the elements of all of the probes to render an image can greatly improve the lateral resolution of the generated image. In order to render an image, the relative positions of all of the elements must be known precisely. A calibration fixture is described in which the probe assembly to be calibrated is placed above a test block and transmits ultrasonic pulses through the test block to an ultrasonic sensor. As the ultrasonic pulses are transmitted though some or all of the elements in the probe to be tested, the differential transit times of arrival of the waveform are measured precisely. From these measurements the relative positions of the probe elements can be computed and the probe can be aligned.

US Patent:

8602993, Dec 10, 2013

Filed:

Aug 7, 2009

Appl. No.:

13/002778

Inventors:

Donald F. Specht - Los Altos CA, US
Kenneth D. Brewer - Santa Clara CA, US

Assignee:

Maui Imaging, Inc. - Sunnyvale CA

International Classification:

A61B 8/00

US Classification:

600437, 600443

Abstract:

The benefits of a multi-aperture ultrasound probe can be achieved with add-on devices. Synchronization and correlation of echoes from multiple transducer elements located in different arrays is essential to the successful processing of multiple aperture imaging. The algorithms disclosed here teach methods to successfully process these signals when the transmission source is coming from another ultrasound system and synchronize the add-on system to the other ultrasound system. Two-dimensional images with different noise components can be constructed from the echoes received by individual transducer elements. The disclosed techniques have broad application in medical imaging and are ideally suited to multi-aperture cardiac imaging using two or more intercostal spaces.

US Patent:

20110201933, Aug 18, 2011

Filed:

Feb 17, 2011

Appl. No.:

13/029907

Inventors:

Donald F. Specht - Los Altos CA, US
Kenneth D. Brewer - Santa Clara CA, US

International Classification:

A61B 8/14

US Classification:

600443

Abstract:

A Multiple Aperture Ultrasound Imaging system and methods of use are provided with any number of features. In some embodiments, a multi-aperture ultrasound imaging system is configured to transmit and receive ultrasound energy to and from separate physical ultrasound apertures. In some embodiments, a transmit aperture of a multi-aperture ultrasound imaging system is configured to transmit an omni-directional unfocused ultrasound waveform approximating a first point source through a target region. In some embodiments, the ultrasound energy is received with a single receiving aperture. In other embodiments, the ultrasound energy is received with multiple receiving apertures. Algorithms are described that can combine echoes received by one or more receiving apertures to form high resolution ultrasound images. Additional algorithms can solve for variations in tissue speed of sound, thus allowing the ultrasound system to be used virtually anywhere in or on the body.

US Patent:

20120057428, Mar 8, 2012

Filed:

Oct 21, 2011

Appl. No.:

13/279110

Inventors:

Donald F. Specht - Los Altos CA, US
Kenneth D. Brewer - Santa Clara CA, US
David M. Smith - Lodi CA, US
Sharon L. Adam - San Jose CA, US
John P. Lunsford - San Carlos CA, US
David J. Specht - San Jose CA, US

International Classification:

G01N 29/30

US Classification:

367 13

Abstract:

A method of calibrating an ultrasound probe includes mounting an ultrasound probe onto a calibration system, transmitting an ultrasound test signal from an element of the probe through a test medium of the calibration system, and receiving the test signal on a matrix of hydrophones such that an element's position relative to other elements and other arrays within the same probe can be computed. Further, the system described herein is configured to detect the acoustic performance of elements of a probe and report the results to an end user or service provider.

US Patent:

20130144166, Jun 6, 2013

Filed:

Nov 30, 2012

Appl. No.:

13/690989

Inventors:

Donald F. SPECHT - Los Altos CA, US
Kenneth D. BREWER - Santa Clara CA, US
David M. SMITH - Lodi CA, US
Josef R. CALL - Campbell CA, US
Tony LE - San Jose CA, US
Bruce R. RITZI - Sunnyvale CA, US

International Classification:

A61B 8/08
A61B 8/14
A61B 8/00

US Classification:

600441, 600453

Abstract:

A method of full-field or “ping-based” Doppler ultrasound imaging allows for detection of Doppler signals indicating moving reflectors at any point in an imaging field without the need to pre-define range gates. In various embodiments, such whole-field Doppler imaging methods may include transmitting a Doppler ping from a transmit aperture, receiving echoes of the Doppler ping with one or more separate receive apertures, detecting Doppler signals and determining the speed of moving reflectors. In some embodiments, the system also provides the ability to determine the direction of motion by solving a set of simultaneous equations based on echo data received by multiple receive apertures.

US Patent:

20130172743, Jul 4, 2013

Filed:

Dec 28, 2012

Appl. No.:

13/730346

Inventors:

Kenneth D. BREWER - Santa Clara CA, US
David M. SMITH - Lodi CA, US
Rozalin M. LORENZATO - Palo Alto CA, US
Bruce R. RITZI - Sunnyvale CA, US

International Classification:

A61B 8/08
A61B 8/14
A61B 8/00

US Classification:

600440

Abstract:

Systems and methods of M-mode ultrasound imaging allows for M-mode imaging along user-defined paths. In various embodiments, the user-defined path can be a non-linear path or a curved path. In some embodiments, a system for M-mode ultrasound imaging can comprise a multi-aperture probe with at least a first transmitting aperture and a second receiving aperture. The receiving aperture can be separate from the transmitting aperture. In some embodiments, the transmitting aperture can be configured to transmit an unfocused, spherical, ultrasound ping signal into a region of interest. The user-defined path can define a structure of interest within the region of interest.

US Patent:

20130218012, Aug 22, 2013

Filed:

Feb 21, 2013

Appl. No.:

13/773340

Inventors:

Donald F. Specht - Los Altos CA, US
Kenneth D. Brewer - Santa Clara CA, US

International Classification:

A61B 8/08
A61B 8/00
G03B 42/06
A61B 8/14

US Classification:

600438, 367 7

Abstract:

Changes in tissue stiffness have long been associated with disease. Systems and methods for determining the stiffness of tissues using ultrasonography may include a device for inducing a propagating shear wave in tissue and tracking the speed of propagation, which is directly related to tissue stiffness and density. The speed of a propagating shear wave may be detected by imaging a tissue at a high frame rate and detecting the propagating wave as a perturbance in successive image frames relative to a baseline image of the tissue in an undisturbed state. In some embodiments, sufficiently high frame rates may be achieved by using a ping-based ultrasound imaging technique in which unfocused omni-directional pings are transmitted (in an imaging plane or in a hemisphere) into a region of interest. Receiving echoes of the omnidirectional pings with multiple receive apertures allows for substantially improved lateral resolution.