公开(公告)号：US5005419A

公开(公告)日：1991-04-09

申请号：US207532

申请日：1988-06-16

申请人： Matthew O'Donnell ,  Kenneth B. Welles, II ,  Carl R. Crawford ,  Norbert J. Pelc ,  Steven G. Karr

发明人： Matthew O'Donnell ,  Kenneth B. Welles, II ,  Carl R. Crawford ,  Norbert J. Pelc ,  Steven G. Karr

IPC分类号： A61B8/00 ,  G01N29/06 ,  G01S7/52 ,  G01S7/526 ,  G01S15/89 ,  G06T1/00

CPC分类号： G01S7/52023 ,  G01S15/8915

摘要： A method and apparatus for improved digital processing of the analog echo signals in a coherent imaging system is described which simplifies the channel circuitry requirements. The analog echo signals detected with a phased array of transducer elements are first compressed in a non-linear manner then expanded non-linearly with analog-to-digital converter means to provide increased instantaneous dynamic range in the overall system. Representative phased array coherent imaging systems having the improved digital processing means are also disclosed.

摘要翻译： 描述了一种用于改进相干成像系统中的模拟回波信号的数字处理的方法和装置，其简化了信道电路要求。 用相控阵的换能器元件检测的模拟回波信号首先以非线性方式压缩，然后以模数转换器装置非线性地扩展，以在整个系统中提供增加的瞬时动态范围。 还公开了具有改进的数字处理装置的代表性相控阵相干成像系统。

公开(公告)号：US4885688A

公开(公告)日：1989-12-05

申请号：US125510

申请日：1987-11-25

申请人： Carl R. Crawford

发明人： Carl R. Crawford

IPC分类号： G09G5/36 ,  G06T17/00

CPC分类号： G06T17/00

摘要： A system for displaying three-dimensional surface structures according to computer graphics methods extracts a surface definition from a tomographic array of data using interpolation of the data for smooth, high resolution images. Interpolation can be performed to a degree where artifact-free images are produced for all viewing orientations. Data-processing capacity and time requirements can be reduced with less interpolation while image quality is maintained for all viewing orientations by inspecting the viewing orientation and appropriately scaling the image.

公开(公告)号：US4626991A

公开(公告)日：1986-12-02

申请号：US487310

申请日：1983-04-21

申请人： Carl R. Crawford ,  Asher Reuveni

发明人： Carl R. Crawford ,  Asher Reuveni

IPC分类号： A61B6/03 ,  G06T1/00 ,  G06T11/00 ,  G06F15/42

CPC分类号： G06T11/006 ,  A61B6/5258 ,  G06T2211/421 ,  Y10S378/901

摘要： A system and method are presented for reprojecting images generated by a back-projector. The image data is processed to distinguish hard and soft tissue and then is transmitted to the normal input of the back-projector. Pseudo-projections (reprojections) are obtained at the normal output of the back-projector. Each image row is fed into the input of the back-projector as a normal projection. The "image" generated by the back-projector is now one projection. In order to generate the required amount of reprojections "L", the image is supplied to the back-projector "L" times. Each time the image is presented with constants, such as the reprojection angle associated with the specific reprojection. The reprojections at the back-projector output are combined in a feed-back circuit with the original projections to correct for artifacts, such as polychromatic artifacts.

摘要翻译： 提出了用于重新投影由背投影仪产生的图像的系统和方法。 处理图像数据以区分硬组织和软组织，然后被传送到背投影机的正常输入。 在背投影机的正常输出处获得伪投影（重投影）。 每个图像行作为正常投影被馈送到背投影机的输入。 由背投产生的“图像”现在是一个投影。 为了产生所需量的重播“L”，图像被提供给背投“L”次。 每次图像呈现常数，例如与特定重投影相关联的重投影角度。 背投投影机输出的重新投影在反馈电路中与原始投影组合在一起，以校正伪像，例如多色伪影。

公开(公告)号：US08151022B2

公开(公告)日：2012-04-03

申请号：US12352322

申请日：2009-01-12

申请人： Albert W. Wegener ,  Carl R. Crawford ,  Yi Ling

发明人： Albert W. Wegener ,  Carl R. Crawford ,  Yi Ling

IPC分类号： G06F13/12 ,  G06F13/38 ,  G06K9/36 ,  G06K9/46

CPC分类号： G06T9/00 ,  H04N19/15 ,  H04N19/17 ,  H04N19/196

摘要： A method and apparatus compress projection data and store the compressed projection data in a rotatable part that is mounted for rotation within a stationary part. The data acquisition source, compressor and storage device are connected to the rotatable part. The compressor compresses projection data samples provided by the data acquisition source to form compressed packets. The compressed packets are stored in the storage device, for example one or more solid state drives mounted on the rotatable part. A data access array contains information related to the location of the stored compressed packets. Compressed packets are retrieved and transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed packets to form decompressed samples of the corresponding projection data. This abstract does not limit the scope of the invention as described in the claims.

摘要翻译： 一种方法和装置压缩投影数据并将压缩的投影数据存储在安装成在静止部分内旋转的可旋转部分中。 数据采集​​源，压缩机和存储设备连接到可旋转部件。 压缩器压缩由数据采集源提供的投影数据样本以形成压缩分组。 压缩的数据包被存储在存储设备中，例如一个或多个安装在可旋转部件上的固态驱动器。 数据访问阵列包含与存储的压缩数据包的位置有关的信息。 压缩的数据包被检索并通过接口传输到固定部分。 固定部分的解压缩器解压缩接收到的压缩数据包，形成相应投影数据的解压缩样本。 该摘要并不限制如权利要求中所述的本发明的范围。

公开(公告)号：US20100128998A1

公开(公告)日：2010-05-27

申请号：US12352322

申请日：2009-01-12

申请人： Albert W. Wegener ,  Carl R. Crawford ,  Yi Ling

发明人： Albert W. Wegener ,  Carl R. Crawford ,  Yi Ling

IPC分类号： G06K9/46

CPC分类号： G06T9/00 ,  H04N19/15 ,  H04N19/17 ,  H04N19/196

摘要： A method and apparatus compress projection data and store the compressed projection data in a rotatable part that is mounted for rotation within a stationary part. The data acquisition source, compressor and storage device are connected to the rotatable part. The compressor compresses projection data samples provided by the data acquisition source to form compressed packets. The compressed packets are stored in the storage device, for example one or more solid state drives mounted on the rotatable part. A data access array contains information related to the location of the stored compressed packets. Compressed packets are retrieved and transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed packets to form decompressed samples of the corresponding projection data. This abstract does not limit the scope of the invention as described in the claims.

摘要翻译： 一种方法和装置压缩投影数据并将压缩的投影数据存储在安装成在静止部分内旋转的可旋转部分中。 数据采集​​源，压缩机和存储设备连接到可旋转部件。 压缩器压缩由数据采集源提供的投影数据样本以形成压缩分组。 压缩的数据包被存储在存储设备中，例如一个或多个安装在可旋转部件上的固态驱动器。 数据访问阵列包含与存储的压缩数据包的位置有关的信息。 压缩的数据包被检索并通过接口传输到固定部分。 固定部分的解压缩器解压缩接收到的压缩数据包，形成相应投影数据的解压缩样本。 该摘要并不限制如权利要求中所述的本发明的范围。

公开(公告)号：US5970113A

公开(公告)日：1999-10-19

申请号：US948928

申请日：1997-10-10

申请人： Carl R. Crawford ,  Hans J. Weedon ,  Christopher C. Ruth

发明人： Carl R. Crawford ,  Hans J. Weedon ,  Christopher C. Ruth

IPC分类号： G01V5/00 ,  G01N23/00

CPC分类号： G01V5/005

摘要： A method and apparatus for performing CT scans of baggage being carried or loaded onto commercial aircraft are described. The CT baggage scanner of the invention includes numerous features which provide the system with high baggage throughput on the order of seven hundred bags per hour as well as improved image quality and accurate target detection. In one aspect, the scanner includes an adaptive image reconstruction window which identifies data collected from the field of view that are not related to the baggage being scanned. These unrelated data are excluded from the image reconstruction process, resulting in greatly reduced reconstruction time and increased baggage throughput. The invention also includes the capability of performing calibration "air scans" with objects such as the system conveyor in the field of view. Data gathered during the calibration scan are applied to a threshold, and data exceeding the threshold are assumed to be from X-rays that are unobstructed by objects in the field of view and are therefore used to perform the air calibration. The baggage scanner can also analyze scan data to identify shapes of objects, particularly, objects formed in the shape of a sheet. This greatly improves the ability of the system to detect sheet explosives. The system also compensates for detector dark currents and provides dark current offsets which can be dependent upon detector temperature.

摘要翻译： 描述了用于对携带或加载到商用飞机上的行李进行CT扫描的方法和装置。 本发明的CT行李扫描器包括许多特征，为系统提供每小时七百袋的高行李吞吐量，以及改进的图像质量和精确的目标检测。 在一个方面，扫描器包括自适应图像重建窗口，其识别从视场收集的与正在扫描的行李无关的数据。 这些不相关的数据从图像重建过程中排除，从而大大减少了重建时间和增加了行李吞吐量。 本发明还包括在视场中执行诸如系统输送机之类的物体的校准“空气扫描”的能力。 在校准扫描期间收集的数据被应用于阈值，并且超过阈值的数据被假设为来自视场中的物体不受阻挡的X射线，因此用于执行空气校准。 行李扫描器还可以分析扫描数据以识别物体的形状，特别是形成为片状形状的物体。 这大大提高了系统检测片状炸药的能力。 该系统还补偿检测器暗电流，并提供暗电流偏移，这取决于检测器温度。

公开(公告)号：US5887047A

公开(公告)日：1999-03-23

申请号：US948697

申请日：1997-10-10

申请人： Eric M. Bailey ,  Carl R. Crawford ,  Alexander I. Greenberg ,  Christopher C. Ruth

发明人： Eric M. Bailey ,  Carl R. Crawford ,  Alexander I. Greenberg ,  Christopher C. Ruth

IPC分类号： A61B6/03 ,  G01N23/04 ,  G06T15/00

CPC分类号： A61B6/032 ,  A61B6/027 ,  Y10S378/901

摘要： A nutating slice CT image reconstruction apparatus and method generates a set of projection data using helical cone-beam scanning. The three-dimensional projection data is used to reconstruct a series of planar image slices. The slices are selected such that they define a tilt angle and a rotation angle with respect to the longitudinal axes of the object being scanned. Successive slices have equal tilt angles but changing rotation angles such that normal axes of successive slices define a nutation and precession about the longitudinal axis of the object. Projection data for the tilted slices are formed of selected one-dimensional fan-beam data. As such, the projection data can be applied to conventional two-dimensional reconstruction approaches to generate an image. The projection data can also be used to generate two-dimensional projection images at one or more stationary projection angles through an object being scanned. The nutation or tilt of image volume elements can be compensated for to provide a more accurate image and more accurate target assessment such as accurate total mass determination. A parallel processing architecture can be used to generate and process the nutated slices with improved efficiency.

摘要翻译： 章动切片CT图像重建装置和方法使用螺旋锥束扫描产生一组投影数据。 三维投影数据用于重建一系列平面图像切片。 切片被选择为使得它们相对于被扫描物体的纵向轴线限定倾斜角度和旋转角度。 连续切片具有相等的倾斜角度，但是改变旋转角度，使得连续切片的法线定义关于物体的纵向轴线的章动和进动。 倾斜切片的投影数据由选定的一维扇形光束数据形成。 因此，投影数据可以应用于常规的二维重建方法以产生图像。 投影数据还可用于通过被扫描物体在一个或多个固定投影角度产生二维投影图像。 可以补偿图像体积元件的章动或倾斜，以提供更准确的图像和更准确的目标评估，例如准确的总质量确定。 可以使用并行处理架构来提高效率来生成和处理章程切片。

公开(公告)号：US5396528A

公开(公告)日：1995-03-07

申请号：US723361

申请日：1991-06-28

申请人： Hui Hu ,  Carl R. Crawford ,  Armin H. Pfoh ,  Jiang Hsieh

发明人： Hui Hu ,  Carl R. Crawford ,  Armin H. Pfoh ,  Jiang Hsieh

IPC分类号： A61B6/03 ,  G01N23/04 ,  G01N23/083

CPC分类号： A61B6/032 ,  A61B6/4085 ,  Y10S378/901

摘要： A CT apparatus employing a cone beam of x-rays reduces image artifacts by employing full as opposed to half scans of less than 360.degree.. The present invention recognizes that rays of a cone beam that cross the imaging plane are not redundant with opposing rays in the scan, as is the case with the rays within the imaging plane. In a second embodiment, half scans of less than 360.degree. are obtained using in-plane and cross-plane rays of the cone beam and the data from the in-plane rays is used to estimate the missing data from that collected with the cross-plane rays.

摘要翻译： 使用X射线锥形束的CT装置通过采用与小于360度的半扫描相反的方式来减少图像伪影。 本发明认识到，如同成像平面内的射线的情况一样，穿过成像平面的锥形束的射线在扫描中与相对的射线不是冗余的。 在第二实施例中，使用锥形束的平面内和平面光线获得小于360°的半扫描，并且使用来自平面内射线的数据来估计从交叉点收集的数据中丢失的数据， 飞机射线

公开(公告)号：US5361291A

公开(公告)日：1994-11-01

申请号：US796113

申请日：1991-11-20

申请人： Thomas L. Toth ,  Carl R. Crawford ,  Kevin F. King

发明人： Thomas L. Toth ,  Carl R. Crawford ,  Kevin F. King

IPC分类号： A61B6/03 ,  G06T11/00 ,  G01N23/083

CPC分类号： A61B6/032 ,  A61B6/4021 ,  G06T11/005 ,  Y10S378/901

摘要： A CT apparatus for reducing aliasing in reconstructed images uses an x-ray tube with a translatable focal spot to double the spatial sampling rate, over that achieved by a conventional CT machine. Radial resolution artifacts in the image, identified to the "bleeding through" of previous samples from different focal spot positions into the present sample are removed by a convolution process employing the inverse of the detector transfer function. Timing of the data sampling with respect to the changing of the wobble positions is also employed to minimize the bleed through and to improve signal-to-noise ratio.

摘要翻译： 用于减少重建图像中的混叠的CT装置使用具有可平移焦点的X射线管将空间采样速率提高一倍，超过常规CT机实现的。 通过使用检测器传递函数的倒数的卷积处理，去​​除了识别为从先前样品从不同焦斑位置到本样品的“渗透”的图像中的径向分辨率伪像。 关于摆动位置改变的数据采样的定时也用于使渗流最小化并提高信噪比。

公开(公告)号：US5270923A

公开(公告)日：1993-12-14

申请号：US430372

申请日：1989-11-02

申请人： Kevin F. King ,  Albert H. R. Lonn ,  Carl R. Crawford

发明人： Kevin F. King ,  Albert H. R. Lonn ,  Carl R. Crawford

IPC分类号： G01N23/04 ,  A61B6/03 ,  G01T1/161 ,  G06T1/00 ,  G06T11/00 ,  H04N1/04 ,  H04N3/30 ,  G06F15/42

CPC分类号： A61B6/032 ,  A61B6/027 ,  G06T11/005

摘要： A method of reducing image artifacts in images acquired with fan beam, helical scanning, tomographic imaging systems uses half scans of less than 360.degree. of projection data of an imaged object on each side of the slice plane being imaged. The half scans are weighted with half scan weighting factors to compensate for redundant data and are weighted with helical scanning weighting factors to interpolate the half scans projection data to projection data at the slice plane. The imaged object may be moved one slice thickness for each 360.degree. of scanning so that the half scans are concentrated closer to the slice plane thereby reducing interpolation errors. Alternatively, for a series of slice images, the imaged object may be moved one slice thickness for each half scan to reduce average slice acquisition time.