Abstract: Ultrasound imaging adapts as a function of a coherence factor. Various beamforming, image forming or image processing parameters are varied as a function of a coherence factor to improve detail resolution, contrast resolution, dynamic range or SNR. For example, a beamforming parameter such as the transmit or receive aperture size, apodization type or delay is selected to provide maximum coherence. Alternatively or additionally, an image forming parameter, such as the number of beams for coherent synthesis or incoherent compounding, is set as a function of the coherence factor. Alternatively or additionally an image processing parameter such as the dynamic range, linear or nonlinear video filter and/or linear or nonlinear map may also adapt as a function of the coherence factor.

Abstract: Disclosed is focus control method for Delta-Sigma based image formation devices in which a steering term and a focusing term of a delay formula are respectively quantized, and corresponding two channels at both sides of the probe are synchronized by a delay produced during dynamic focusing. During synchronizing the two channels, two numeral values with equal absolute value but with opposite signs are respectively inserted so as to eliminate extra noise the signals are after summing up, and controlling common delay of the two channels is performed by same one controller. After summing up the inserted two values, the dynamic aperture control of the Delta-Sigma based image formation device can be effectively realized and noise during dynamic focusing also is eliminated thereby achieving an ideal single bit output.

Abstract: Disclosed is focus control method for Delta-Sigma based image formation devices in which a steering term and a focusing term of a delay formula are respectively quantized, and corresponding two channels at both sides of the probe are synchronized by a delay produced during dynamic focusing. During synchronizing the two channels, two numeral values with equal absolute value but with opposite signs are respectively inserted so as to eliminate extra noise the signals are after summing up, and controlling common delay of the two channels is performed by same one controller. After summing up the inserted two values, the dynamic aperture control of the Delta-Sigma based image formation device can be effectively realized and noise during dynamic focusing also is eliminated thereby achieving an ideal single bit output.

Abstract: Methods perform dynamic focusing of a coherent array imaging system are invented. Dynamic focusing in ultrasonic array imaging involves extensive real-time computations and data communication. Particularly for real-time three-dimensional imaging using fully-sampled two-dimensional arrays, implementation of dynamic focusing can be extremely complicated. The invention described in this disclosure greatly simplifies the delay control mechanism by exploiting both spatial and temporal characteristics of the focusing delay patterns. The simplification primarily results from (1) grouping adjacent channels into sub-apertures for the range dependent focusing component, and (2) non-uniform quantization of the delay values.

Abstract: A compounding method for reducing speckle noise applied in an ultrasound imaging apparatus is disclosed. The compounding method includes the steps of providing an object, measuring the object for obtaining a reference image by the ultrasound imaging apparatus, applying an external force to the object to deform the object, measuring the deformed object for obtaining an deformed object image at the same position, estimating an in-plane displacement field of the deformed object image for correcting an in-plane motion of the object to obtain a corrected image, and compounding the reference image with the corrected image to obtain a compounded image of the object for achieving the speckle noise reduction.

Abstract: A compounding method for reducing speckle noise applied in an ultrasound imaging apparatus is disclosed. The compounding method includes the steps of providing an object, measuring the object for obtaining a reference image by the ultrasound imaging apparatus, applying an external force to the object to deform the object, measuring the deformed object for obtaining an deformed object image at the same position, estimating an in-plane displacement field of the deformed object image for correcting an in-plane motion of the object to obtain a corrected image, and compounding the reference image with the corrected image to obtain a compounded image of the object for achieving the speckle noise reduction.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: Doppler principle has been widely applied to calculate the velocity of the object in motion. In medical ultrasonic imaging, it can be used to detect blood flow or myocardial motion. However, due to the inherent limitation of the Doppler effect, the measured velocity is only the projection of the actual velocity onto the ultrasound beam direction instead of the actual velocity. In previously proposed methods for measuring or correcting the Doppler angles, some need manual correction, others use complicated algorithms. They are either inconvenient to use or difficult to implement in current systems. In the method of Doppler motion detection with automatic angle correction according to the instant invention, it focuses on the relation between the Doppler angle and signal bandwidth to compute the Doppler angle by efficient correlation processing. Specifically, it uses variance of the Doppler signal to approximate square of the Doppler bandwidth.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or booth. By properly selecting the frequency pass bands, of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: A display processor for an ultrasonic imaging system includes a two-dimensional filter to generate a smoothed image signal I.sub.p from a high spatial resolution image signal I.sub.D. I.sub.p is optimized for high contrast resolution and good tissue differentiation, and I.sub.D is optimized for high detail resolution and the display of fine structural details. I.sub.p and I.sub.D are applied as addressing inputs to a look-up table that provides an output image signal I.sub.O that combines both detail resolution of I.sub.D and contrast resolution of I.sub.p. I.sub.O can display detail resolution as brightness and contrast resolution as color. I.sub.O can also be formed as a weighted combination or sum of I.sub.p and I.sub.D.