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公开(公告)号：US4288695A
公开(公告)日：1981-09-08
申请号：US29877
申请日：1979-04-13
CPC分类号： A61B6/032 , A61B6/4035 , G06T11/005 , G21K1/10
摘要： The invention comprises a shaped filter and a filter correction circuitry for computerized tomographic scanners. The shaped filter is a generally U-shaped block of filter material which is adapted to be mounted between the source of radiation and the scan circle. The U-shaped block has a parabolic recess. The filter material may be beryllium, aluminum, sulphur, calcium, titanium, erbium, copper, and compounds including oxides and alloys thereof. The filter correction circuit comprises a first filter correction profile adding circuit for adding a first scaler valve to each intensity valve in a data line. The data line is operated on by a beam hardness correction polynomial. After the beam hardness polynomial correction operation, a second filter correction circuit adds a second filter correction profile consisting of a table of scalor values, one corresponding to each intensity reading in the data line.
摘要翻译： 本发明包括用于计算机断层扫描仪的成形过滤器和过滤器校正电路。 成形过滤器是大体上U形的过滤材料块，其适于安装在辐射源和扫描圆之间。 U形块具有抛物线凹槽。 过滤材料可以是铍，铝，硫，钙，钛，铒，铜，以及包括氧化物及其合金的化合物。 滤波器校正电路包括第一滤波器校正曲线添加电路，用于将第一缩放阀添加到数据线中的每个强度阀。 数据线通过光束硬度校正多项式进行操作。 在光束硬度多项式校正操作之后，第二滤光器校正电路添加由量化值表构成的第二滤波器校正曲线，一个对应于数据线中的每个强度读数。
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2.发明授权Method of high resolution partial area scan involving concentrated high density material outside the partial area 失效高分辨率部分区域扫描方法涉及部分区域以外的集中高密度材料
公开(公告)号：US4333145A
公开(公告)日：1982-06-01
申请号：US98431
申请日：1979-11-29
CPC分类号： A61B6/483 , A61B6/032 , A61B6/4275 , G06T11/005 , G06T2211/421 , Y10S378/901
摘要： A method of minimizing a streaking effect found in reconstructed images obtained from high resolution CT scanning of a small scan circle that corresponds to a limited region of interest, such as portions of the spinal cord of a patient, particularly in scans that include concentrated high density material, such as bone, situated outside the small scan circle. The approximate range of view angles that will project bone from outside the limited region of interest is determined. Detectors corresponding to the determined region are selected out. The projection data acquired by the selected detectors is filtered. The filtering is accomplished by convolving the projection data with a preselected filter function or in machine implemented form by passing the electrical signal representing the projection data through a low pass filter.
摘要翻译： 一种最小化重建图像中发现的条纹效应的方法，该重建图像从对应于感兴趣的有限区域（例如患者的脊髓部分）的小扫描圆的高分辨率CT扫描获得，特别是在包括浓度高密度 材料，如骨头，位于小扫描圈外。 确定从有限的感兴趣区域外部投射骨骼的视角的近似范围。 选择对应于确定区域的检测器。 由所选择的检测器获取的投影数据被滤波。 通过将表示投影数据的电信号通过低通滤波器将预测滤波器函数或机器实现形式的投影数据进行卷积来实现滤波。
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公开(公告)号：US4577340A
公开(公告)日：1986-03-18
申请号：US533706
申请日：1983-09-19
CPC分类号： H01J35/106 , H01J35/16
摘要： An all metal and ceramic high vacuum rotary anode X-ray tube adapted for mounting on a gantry of a rotational type CT scanner. The evacuated region where X-rays are generated is maintained at about 10.sup.-7 Torr. Vacuum sealing about the rotating shaft of the anode is provided by a magnetic fluid. No bearings are utilized within the evacuated region. Large, long wearing ball bearings that transmit rotation through the vacuum seal are provided about the shaft outside of the high vacuum region where conventional lubricants may be applied. Circulating coolant is applied internally through the anode assuring continual operation of the tube without the need for frequent cool-down waits.
摘要翻译： 全金属和陶瓷高真空旋转阳极X射线管，适用于安装在旋转式CT扫描仪的台架上。 产生X射线的抽空区域保持在约10-7乇。 围绕阳极的旋转轴的真空密封由磁性流体提供。 在抽空区域内没有使用轴承。 通过真空密封件传递旋转的大型长磨损球轴承设置在可以施加常规润滑剂的高真空区域外侧的轴上。 循环冷却液通过阳极内部施加，确保管的连续操作，而不需要频繁的冷却等待。
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公开(公告)号：US4466112A
公开(公告)日：1984-08-14
申请号：US344244
申请日：1982-01-29
申请人： John Covic , Roland W. Carlson
发明人： John Covic , Roland W. Carlson
CPC分类号： A61B6/4476 , A61B6/06 , G01N23/046 , G01N2223/419 , G01N2223/612
摘要： In a rotating fan beam tomographic scanner there is included a variable detector aperture housed within a radiation scatter shield. The scanner includes a diverging source of penetrating radiation which is directed toward a patient receiving section for passing a fan shaped beam of radiation through a planar section of the patient. The incident radition beam is attenuated during its passage through the patient receiving section and the transmitted beam passes from the patient receiving section until it impinges on a plurality of detectors for eventual reconstruction into a visible image. The variable detector aperture controls the thickness of the fan shaped beam and hence limits the amount of radiation impinging on the detectors. The aperture includes a pair of elongated beam thickness defining members having an opening therebetween and rotatable relative to the scanning plane. The opening between the two members in a direction transverse to the scanning plane defines the thickness of the attenuated fan beam passing therethrough.
摘要翻译： 在旋转风扇束断层扫描仪中，包括容纳在辐射散射屏蔽内的可变探测器孔。 该扫描仪包括一个穿透辐射源，该辐射源指向患者接收部分，用于使扇形辐射束通过患者的平面部分。 入射光束在其通过患者接收部分期间被衰减，并且所发射的光束从患者接收部分通过，直到其撞击到多个检测器以最终重建为可见光图像。 可变检测器孔径控制扇形梁的厚度，因此限制了入射到检测器上的辐射量。 该孔包括一对细长的梁厚度限定构件，其具有在其间的开口并且可相对于扫描平面旋转。 两个构件之间的横向于扫描平面的方向上的开口限定了通过其中的衰减的扇形束的厚度。
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公开(公告)号：US5138642A
公开(公告)日：1992-08-11
申请号：US471856
申请日：1990-01-29
CPC分类号： G01N23/046 , G01N23/043 , G21K1/00 , G01N2223/419
摘要： A detector arrangement is disclosed for an industrial CT x-ray system which uses a three dimensional cone beam to irradiate the specimen and a large two dimensional scintillation screen to develop a light image corresponding to the energy of the attenuated radiation beams. The light image is focused by a special lens arrangement with zoom capability onto the photocathode of an intensifier. The intensified light image developed is transmitted by fiberoptics to a plurality of CCD chips, each chip developing electrical signals corresponding to a segment of the image developed in the intensifier. The chips are clocked in a predetermined manner based on a prior information developed in an initial scan to produce a high resolution image of large industrial objects in a short time.
摘要翻译： 公开了一种用于工业CT X射线系统的检测器装置，其使用三维锥形束来照射样本和大的二维闪烁屏以形成对应于衰减的辐射束的能量的光图像。 光图像通过具有变焦能力的特殊透镜布置聚焦到增强器的光电阴极上。 显影的增强的光图像通过光纤传输到多个CCD芯片，每个芯片显影对应于在增强器中显影的图像的段的电信号。 基于在初始扫描中开发的先前信息以预定方式对芯片进行计时，以在短时间内产生大型工业物体的高分辨率图像。
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公开(公告)号：US4501566A
公开(公告)日：1985-02-26
申请号：US533704
申请日：1983-09-19
CPC分类号： H01J35/16 , H01J35/101 , H01J2235/1266 , Y10S277/913 , Y10T29/49888
摘要： A method of vacuum assembling a rotating anode X-ray tube of the type having a rotor and a shaft extending therefrom with a magnetic fluid for vacuum sealing about the shaft. The tube is subjected to a high temperature bake-out whereby gases are sufficiently evolved from exposed metal parts that a stable low pressure region is created. A static seal is used to temporarily seal the region during bake-out with the anode temporarily rendered non-rotatable and the permanent magnetic vacuum seal protected from the high temperature. The system is then allowed to cool off before the permanent magnetic vacuum seal is moved into its operational position within the high vacuum. Assembly tooling is provided ensuring that the high vacuum is maintained throughout the installation. Bearings are installed external to the region of high vacuum to transmit rotary motion of the shaft through the permanent seal. Finally, the tube is rendered operational by displacing the static seal thereby permitting the anode to be rotated.
摘要翻译： 一种真空组装旋转阳极X射线管的方法，该旋转阳极X射线管具有转子和从其延伸的轴与用于真空密封轴的磁性流体。 对管进行高温烘烤，从而从暴露的金属部分充分放出气体，从而产生稳定的低压区域。 使用静态密封件在烘烤期间临时密封该区域，阳极暂时不可旋转，并且永久磁性真空密封件防止高温。 然后在永磁真空密封件在高真空中移动到其操作位置之前，使系统冷却。 提供组装工具，确保在整个安装过程中保持高真空度。 轴承安装在高真空区域外部，以通过永久性密封件传递轴的旋转运动。 最后，通过移动静态密封件使管子变得可操作，从而允许阳极旋转。
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公开(公告)号：US4625324A
公开(公告)日：1986-11-25
申请号：US579068
申请日：1984-02-10
CPC分类号： H01J35/106 , H01J35/16
摘要： An all metal and ceramic high vacuum rotary anode x-ray tube adapted for mounting on a gantry of a rotational type CT scanner. The evacuated region where x-rays are generated is maintained at about 10.sup.-7 Torr. Vacuum sealing about the rotating shaft of the anode is provided by a magnetic fluid. No bearings are utilized within the evacuated region. Large, long wearing ball bearings that transmit rotation through the vacuum seal are provided about the shaft outside of the high vacuum region where conventional lubricants may be applied. Circulating coolant is applied internally through the anode assuring continual operation of the tube without the need for frequent cool-down waits. A preferred embodiment discloses a modified path in the rotor for the coolant designed to disturb the conventional laminar type of flow which is heat transfer inefficient to one characterized by high turbulence resulting in approximately an order of magnitude improvement in the coefficient of heat transfer.
摘要翻译： 全金属和陶瓷高真空旋转阳极x射线管适用于安装在旋转式CT扫描仪的机架上。 产生X射线的抽空区域保持在约10-7乇。 围绕阳极的旋转轴的真空密封由磁性流体提供。 在抽空区域内没有使用轴承。 通过真空密封件传递旋转的大型长磨损球轴承设置在可以施加常规润滑剂的高真空区域外侧的轴上。 循环冷却液通过阳极内部施加，确保管的连续操作，而不需要频繁的冷却等待。 优选实施例公开了用于冷却剂的转子中的改进路径，其被设计成干扰传统的层流型流动，其传热效率低于以高湍流为特征的特征，导致传热系数提高大约一个数量级。
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公开(公告)号：US4398092A
公开(公告)日：1983-08-09
申请号：US265714
申请日：1981-05-20
申请人： Roland W. Carlson
发明人： Roland W. Carlson
CPC分类号： G01T1/202 , A61B6/032 , G01T1/1644
摘要： A radiation detector or detector array which has a non-constant spatial response individually and in combination with a tomographic scanner. The detector has a first dimension which is oriented parallel to the plane of the scan circle in the scanner. Along the first dimension, the detector is most responsive to radiation received along a centered segment of the dimension and less responsive to radiation received along edge segments. This non-constant spatial response can be achieved in a detector comprised of a scintillation crystal and a photoelectric transducer. The scintillation crystal in one embodiment is composed of three crystals arranged in layers, with the center crystal having the greatest light conversion efficiency. In a preferred embodiment, the non-constant spatial response is achieved in a detector comprised of a single scintillation crystal whose response is shaped by inducing along said first dimension a scintillation conversion efficiency gradient. In the single crystal embodiment, the gradient is chosen so that the crystal has greater conversion efficiency centrally than peripherally.
摘要翻译： 辐射检测器或检测器阵列，其独立地具有非恒定的空间响应并与断层扫描仪组合。 检测器具有平行于扫描器中的扫描圆的平面的第一尺寸。 沿着第一维度，检测器对沿着尺寸的中心部分接收的辐射响应最大，并且对沿着边缘段接收的辐射的响应较小。 这种非恒定的空间响应可以在由闪烁晶体和光电换能器组成的检测器中实现。 一个实施例中的闪烁晶体由三层晶体组成，中心晶体具有最大的光转换效率。 在优选实施例中，非恒定空间响应在包括单个闪烁晶体的检测器中实现，其响应通过沿着所述第一维度引入闪烁转换效率梯度而成形。 在单晶实施例中，选择梯度使得晶体比周边集中地具有更大的转换效率。
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公开(公告)号：US4292538A
公开(公告)日：1981-09-29
申请号：US64835
申请日：1979-08-08
申请人： Roland W. Carlson
发明人： Roland W. Carlson
CPC分类号： G01T1/202 , A61B6/032 , G01T1/1644
摘要： A radiation detector or detector array which has a non-constant spatial response, is disclosed individually and in combination with a tomographic scanner. The detector has a first dimension which is oriented parallel to the plane of the scan circle in the scanner. Along the first dimension, the detector is most responsive to radiation received along a centered segment of the dimension and less responsive to radiation received along edge segments. This non-constant spatial response can be achieved in a detector comprised of a scintillation crystal and a photoelectric transducer. The scintillation crystal in one embodiment is composed of three crystals arranged in layers, with the center crystal having the greatest light conversion efficiency. In another embodiment, the crystal is covered with a reflective substance around the center segment and a less reflective substance around the remainder. In another embodiment, an optical coupling which transmits light from adjacent the center segment with the greatest intensity couples the scintillation crystal and the photoelectric transducer. In yet another embodiment, the photoelectric transducer comprises three photodiodes, one receiving light produced adjacent the central segment and the other two receiving light produced adjacent the edge segments. The outputs of the three photodiodes are combined with a differential amplifier.
摘要翻译： 具有非恒定空间响应的辐射检测器或检测器阵列单独地公开并与断层扫描器组合。 检测器具有平行于扫描器中的扫描圆的平面的第一尺寸。 沿着第一维度，检测器对沿着尺寸的中心部分接收的辐射响应最大，并且对沿着边缘段接收的辐射的响应较小。 这种非恒定的空间响应可以在由闪烁晶体和光电换能器组成的检测器中实现。 一个实施例中的闪烁晶体由三层晶体组成，中心晶体具有最大的光转换效率。 在另一个实施例中，晶体被中心片周围的反射物体覆盖，而在其余部分周围的反射物质较少。 在另一个实施例中，以最大强度透射来自相邻中心部分的光的光学耦合将闪烁晶体和光电变换器耦合。 在另一个实施例中，光电变换器包括三个光电二极管，一个接收邻近中心段产生的光，而另外两个接收邻近边缘段产生的光。 三个光电二极管的输出与差分放大器组合。
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公开(公告)号：US4277685A
公开(公告)日：1981-07-07
申请号：US914361
申请日：1978-06-12
申请人： John Covic , Glen Leininger , Roland W. Carlson
发明人： John Covic , Glen Leininger , Roland W. Carlson
CPC分类号： G03B42/02
摘要： In a rotating fan beam tomographic scanner there is included an adjustable collimator and shutter assembly. The assembly includes a fan angle collimation cylinder having a plurality of different length slots through which the beam may pass for adjusting the fan angle of the beam. It also includes a beam thickness cylinder having a plurality of slots of different widths for adjusting the thickness of the beam. Further, some of the slots have filter materials mounted therein so that the operator may select from a plurality of filters. Also disclosed is a servo motor system which allows the operator to select the desired fan angle, beam thickness and filter from a remote location. An additional feature is a failsafe shutter assembly which includes a spring biased shutter cylinder mounted in the collimation cylinders. The servo motor control circuit checks several system conditions before the shutter is rendered openable. Further, the circuit cuts off the radiation if the shutter fails to open or close properly. A still further feature is a reference radiation intensity monitor which includes a tuning-fork shaped light conducting element having a scintillation crystal mounted on each tine. The monitor is placed adjacent the collimator between it and the source with the pair of crystals to either side of the fan beam.
摘要翻译： 在旋转风扇光束断层扫描仪中，包括可调整的准直仪和快门组件。 组件包括具有多个不同长度的狭槽的扇形角准直圆柱体，光束可以通过该狭槽来调节光束的扇角。 它还包括具有不同宽度的多个狭槽的光束厚度圆柱体，用于调节光束的厚度。 此外，一些槽具有安装在其中的过滤材料，使得操作者可以从多个过滤器中进行选择。 还公开了一种伺服电动机系统，其允许操作者从远程位置选择所需的风扇角度，梁厚度和过滤器。 一个附加的特征是故障保护快门组件，其包括安装在准直气缸中的弹簧偏压快门柱。 伺服电机控制电路在快门可打开之前检查几个系统状况。 此外，如果快门未正确打开或关闭，则电路切断辐射。 另外的特征是参考辐射强度监视器，其包括具有安装在每个齿上的闪烁晶体的音叉形光导元件。 将监视器放置在其与源之间的准直器附近，并且将一对晶体放置在风扇光束的任一侧。
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