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公开(公告)号：EP0594840A1
公开(公告)日：1994-05-04
申请号：EP93912350.0
申请日：1993-04-23
申请人： LUNAR CORPORATION
发明人： PELC, Norbert, J.
CPC分类号： A61B6/505 , A61B6/4035 , A61B6/482 , H05G1/60
摘要： L'invention se rapporte à un double système (10) d'énergie à rayons x destiné à déterminer la densité osseuse et analogue qui compense la densité de flux variable associée aux différentes absorptions, et la production de fortes et faibles énergies de rayons X par la régulation des deux tensions polarisant le tube à rayons X et les temps d'arrêt relatifs durant lesquels le tube à rayons X se trouve soumis à ces tensions, le temps d'arrêt étant augmenté pour que la tension plus basse compense la densité du flux plus faible. La compensation de variation de la densité du flux améliore le rapport signal/bruit obtenu des mesures prises et assure ainsi une mesure plus précise de matériaux avec un temps d'observation réduit.
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22.发明公开Method and apparatus for digital control of scanning X-ray imaging systems 失效Verfahren und Apparat zur digitalen Steuerung von Bildabtastvorrichtungen mittelsRöntgenstrahlen。
公开(公告)号：EP0593253A1
公开(公告)日：1994-04-20
申请号：EP93308105.1
申请日：1993-10-12
摘要： X-ray images are produced on a monitor display screen (32) by situating the subject between a detector (13) having a minute x-ray sensitive area and an x-ray source (12) having an extensive anode plate (18) on which an x-ray origin point is swept in a raster pattern similar to the raster of the display monitor. Operating parameters of the x-ray source are controlled by digital data processing circuits (43) which enable magnification of operator selected areas of the image by reducing the size of x-ray source raster pattern and repositioning of the raster pattern on the anode plate in response to operator actuation of one or more computer input devices.
In the preferred form, the system also enables image enhancements and control of image characteristics such as contrast and brightness in response to actuations of the input devices or in response to programming. X-ray exposure and image acquisition time may be reduced by operator selection of only specific areas of particular interest for high resolution scanning. In the preferred form, the apparatus can detect a particular gray level in the image data and relocate the scan to image the region where the gray level is found. This enables fixed imaging of a moving object.摘要翻译： X射线图像通过在具有微小的x射线敏感区域的检测器（13）和具有广泛的阳极板（18）的x射线源（12）之间使被摄体位于其上而在监视器显示屏幕（32）上产生 其以与显示监视器的光栅相似的光栅图案扫描x射线原点。 x射线源的操作参数由数字数据处理电路（43）控制，数字数据处理电路（43）可以通过减小X射线源光栅图案的尺寸和使阳极板上的光栅图案重新定位，从而放大操作者所选择的图像区域 响应于一个或多个计算机输入设备的操作者致动。 在优选形式中，该系统还能够响应于输入设备的启动或响应于编程而使图像增强和图像特性（例如对比度和亮度）的控制。 X射线曝光和图像采集时间可以通过操作者仅选择特定感兴趣的特定区域来进行高分辨率扫描。 在优选形式中，该装置可以检测图像数据中的特定灰度级，并将扫描重新定位成图像发现灰度级的区域。 这使得能够对移动物体进行固定成像。
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公开(公告)号：EP0587648A1
公开(公告)日：1994-03-23
申请号：EP92911202.0
申请日：1992-06-01
发明人： NELVIG, Per
摘要： Procédé et dispositif concernant la technique d'utilisation d'un élément capteur d'images, de préférence une cellule à charge couplée au lieu d'un film sensible aux rayons X. Ce procédé et dispositif peuvent s'appliquer à un appareil radiographique sans qu'une liaison directe soit nécessaire entre l'élément capteur d'images et l'appareil radiographique, en utilisant un certain nombre de points de détection pour les rayons X au niveau de la cellule à charge couplée ou dans cette dernière. De plus, un procédé et un dispositif permettant d'abaisser la dose de rayonnement au niveau exact nécessaire pour l'exposition d'une image, ce qui implique, selon la présente invention, que l'on puisse obtenir plus d'images pour une même dose de rayonnement normale totale, est également décrit.
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公开(公告)号：EP0564551A4
公开(公告)日：1994-03-09
申请号：EP92902862
申请日：1991-12-23
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25.发明公开X-ray examination apparatus having means for correcting scattered-radiation effects in an x-ray image 失效X射线检查设备具有用于校正X射线图像中的散射辐射效应的装置
公开(公告)号：EP0565171A3
公开(公告)日：1994-01-05
申请号：EP93200921.0
申请日：1993-03-31
发明人： Kemner, Rudolf
摘要： It is known that perturbations caused by scattered-radiation in an x-ray image can be partially avoided by employing a scattered-radiation grid. A device for further improvement of an x-ray image, in that real-time correction of scattered-radiation effects is achieved, is provided according to the invention. Behind x-ray absorbing parts of the scattered-radiation grid only scattered-radiation appears, whereas both scattered-radiation and primary radiation appear behind transparent channels of the scattered-radiation grid. The scattered-radiation grid gives rise to a high-frequency intensity modulation in the x-ray image. From the high-frequency component of the corresponding video signal produced by the x-ray detector, selection signals are generated by a double pulse generator for distinguishing signal amplitudes of the video signal, corresponding to intensities behind absorbing parts and transparent parts , respectively, of the scattered-radiation grid. The selection signals are supplied to a synchronous detector to split the video signal from the x-ray detector into separated video signals corresponding to scattered-radiation and primary radiation and to scattered-radiation only, respectively. A video signal corresponding to a corrected image is obtained by subtraction of the separated video signals.
摘要翻译： 已知可以通过采用散射辐射网格来部分地避免由X射线图像中的散射辐射引起的扰动。 根据本发明提供了一种用于进一步改善X射线图像的装置，其实现了散射辐射效应的实时校正。 在散射辐射网格的X射线吸收部分后面仅出现散射辐射，而散射辐射和主辐射出现在散射辐射网格的透明通道后面。 散射辐射栅格在X射线图像中引起高频强度调制。 从由X射线检测器产生的相应视频信号的高频分量中，选择信号由双脉冲发生器产生，用于区分视频信号的信号幅度，分别对应于吸收部分和透明部分之后的强度， 散射辐射网格。 选择信号被提供给同步检测器，以将来自X射线检测器的视频信号分离成分别对应于散射辐射和初级辐射的分离视频信号，并分别仅散射辐射。 通过减去分离的视频信号获得对应于校正图像的视频信号。
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26.发明公开X-ray examination apparatus having means for correcting scattered-radiation effects in an x-ray image 失效在einemRöntgenbild的Vorrichtung zurRöntgenuntersuchungmit Korrektur der Streustrahlungseffekte。
公开(公告)号：EP0565171A2
公开(公告)日：1993-10-13
申请号：EP93200921.0
申请日：1993-03-31
发明人： Kemner, Rudolf
摘要： It is known that perturbations caused by scattered-radiation in an x-ray image can be partially avoided by employing a scattered-radiation grid. A device for further improvement of an x-ray image, in that real-time correction of scattered-radiation effects is achieved, is provided according to the invention.
Behind x-ray absorbing parts of the scattered-radiation grid only scattered-radiation appears, whereas both scattered-radiation and primary radiation appear behind transparent channels of the scattered-radiation grid. The scattered-radiation grid gives rise to a high-frequency intensity modulation in the x-ray image. From the high-frequency component of the corresponding video signal produced by the x-ray detector, selection signals are generated by a double pulse generator for distinguishing signal amplitudes of the video signal, corresponding to intensities behind absorbing parts and transparent parts , respectively, of the scattered-radiation grid. The selection signals are supplied to a synchronous detector to split the video signal from the x-ray detector into separated video signals corresponding to scattered-radiation and primary radiation and to scattered-radiation only, respectively. A video signal corresponding to a corrected image is obtained by subtraction of the separated video signals.摘要翻译： 已知通过使用散射辐射网格可以部分地避免由X射线图像中的散射辐射引起的扰动。 根据本发明提供了一种用于进一步改进X射线图像的装置，其中实现了散射辐射效应的实时校正。 散射辐射网格的X射线吸收部分后面只出现散射辐射，而散射辐射和主辐射两者都出现在散射辐射网格的透明通道之后。 散射辐射网格在x射线图像中产生高频强度调制。 根据由X射线检测器产生的相应视频信号的高频分量，选择信号由双脉冲发生器产生，用于区分视频信号的信号幅度，分别对应于吸收部分和透明部分之后的强度 散射辐射网格。 选择信号被提供给同步检测器，以将来自X射线检测器的视频信号分离成分别对应于散射辐射和初级辐射的视频信号，并分别仅分散辐射。 通过减去分离的视频信号获得对应于校正图像的视频信号。
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27.发明公开Imaging system with means for compensating vignetting and X-ray examination apparatus comprising such an imaging system 失效一种成像系统，具有用于补偿的渐晕和含有X射线检查装置这样的成像系统的装置。
公开(公告)号：EP0562657A2
公开(公告)日：1993-09-29
申请号：EP93200666.1
申请日：1993-03-09
CPC分类号： H04N5/3572 , H04N5/32 , H05G1/60
摘要： Loss of brightness at the edges of an image is generally known as vignetting. Non-matching of stops in an optical system or, in particular in x-ray examination apparatus, variations in intensity of the x-ray beam and the combination of the image intensifier and the television camera tube give rise to vignetting. Compensating for vignetting is achieved by electronically multiplying the pixel-values of the vignetted image by a gain characteristic so as to obtain an unperturbed image. A gain characteristic pertaining to a particular vignetting effect is formed by a set of correction factors for all pixels. These correction factors are obtained from the image of an object having a spatially homogeneous brightness distribution. Various gain characteristics can be stored so that compensation for vignetting is sustained when the adjustments of the imaging system are varied.
In order to improve spatial resolution of the image formed on the output screen of an image intensifier in an x-ray examination apparatus a known method splits the image into two sub-images. Either of these images is subsequently detected by an opto-electronic sensor, e.g. a CCD-sensor. These sensors are mutually shifted such that the pixels of one sensor fall at the interstices of the other sensor. Upon recombination of both sub-images an image with improved spatial resolution results. Because of the use of a beam splitter the vignetting effects in either of the sub-images are inevitably different. The vignetting is decomposed in vignetting in a horizontal and in a vertical direction in the recombined image. Correction for vignetting is achieved by multiplying decomposition factors pertaining to horizontal and to vertical vignetting.摘要翻译： 在图像的边缘亮度的损失产生的反弹称为渐晕。 在光学系统的停止非匹配，或者在X射线检查装置particulare，在x射线束的强度和图像增强器的组合和电视摄像管的变化引起的渐晕。 补偿渐晕通过由增益特性电乘以渐晕的图像的像素值，以便获得在未扰动的图像来实现。 属于特定晕影效果的增益特性，通过对所有像素的一组校正因子形成。 这些校正因子是从具有空间均匀的亮度分布的对象的图像而获得的。 各个增益特性可以被存储为没有为渐晕补偿持续当成像系统的调整而变化。 为了改善形成在X射线检查装置中的图像增强器的输出屏上的图像的空间分辨率的公知的方法拆分成图像两个子图像。 无论哪种合成图像随后通过在光电传感器，E.G.检测 CCD传感器。 这些传感器相互偏移检查没有一个传感器事件的像素在另一传感器的空隙。 当两个子图像，以图像具有改善的空间分辨率的结果的复合。 因为使用一个光束的的分路器中的子图像的无论是渐晕效应是不可避免地不同。 渐晕在渐晕在水平方向和在重组图像在垂直方向上分解。 校正渐晕乘以关于水平方向和垂直于渐晕分解因素来实现的。
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28.发明公开
公开(公告)号：EP0518588A3
公开(公告)日：1993-07-21
申请号：EP92305223.7
申请日：1992-06-08
CPC分类号： G06T5/20 , G06T2207/10116 , G06T2207/30004 , H04N5/32 , H05G1/60
摘要： A medical imaging system includes a photodetector array which converts an X-ray image into a series of picture elements arranged in rows and columns of a two dimensional matrix. The picture elements are read from the array on a column by column basis. A spatial filter for the picture elements includes a first filter that applies one filter function to the pixels in each column of the image. The partially filtered pixels are stored in a first memory and then read therefrom row by row in a field interlaced order. The rows of picture elements are sent to a second filter that applies another filter function to each row. The fully filtered picture elements from the second filter either are stored or converted to a video signal for display.
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公开(公告)号：EP0309813B1
公开(公告)日：1992-12-09
申请号：EP88115027.0
申请日：1988-09-14
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30.发明公开Fluoroscopic method with reduced x-ray dosage 失效Fluoroskopisches Verfahren mit verminderterRöntgendosierung。
公开(公告)号：EP0498568A2
公开(公告)日：1992-08-12
申请号：EP92300814.8
申请日：1992-01-30
IPC分类号： H04N5/32
CPC分类号： H04N7/0135 , H04N5/32 , H04N19/587 , H05G1/60
摘要： A method for fluoroscopically observing a living creature with reduced x-ray dosage is usable with a video monitor for displaying frames of image samples received during respective ones of frame scan intervals that regularly and successively occur at a display frame rate sufficiently high that brightness flicker is acceptably low to a human observer; an x-ray source that can be gated on for intervals not as long as a display frame; a fluoroscopic camera, including a raster-scanning video camera and x-ray-to-light conversion apparatus with persistence not appreciably longer than a display frame; and frame filling apparatus for grabbing frames of image samples and interpolating between successively grabbed frames of image samples, when necessary, to generate frames of image samples at said display frame rate. During ones of said successive frame scan intervals, x-ray radiation is directed from the gated x-ray source through the living creature; the x-ray shadow of at least a portion of the living creature is viewed with the fluoroscopic camera; and the frame filling apparatus grabs frames of image samples from the raster-scanning video camera to be stored in frame stores and used as bases from which to compute fill frames of image samples. The frame filling apparatus continuously supplies to the video monitor the frames of image samples it generates at display frame rate.
摘要翻译： 用于透视观察具有减少的X射线剂量的活体的方法可用于视频监视器，用于显示在相应的帧扫描间隔期间接收的图像样本的帧，该帧扫描间隔以足够高的显示帧速率定期连续出现，使得亮度闪烁为 对人类观察者的接受度低; 可以在不显示框架的间隔上选通的X射线源; 荧光相机，包括光栅扫描摄像机和X射线至光转换装置，其持续时间不比显示帧长得多; 以及帧填充装置，用于抓取图像样本的帧并且在必要时在相继抓取的图像样本帧之间进行内插以以所述显示帧速率生成图像样本的帧。 在所述连续帧扫描间隔期间，x射线辐射从门控x射线源通过活体引导; 用荧光镜照相机观察至少一部分生物的x射线阴影; 并且帧填充设备从光栅扫描摄像机中抓取图像样本的帧以存储在帧存储中，并且用作从其计算图像样本的填充帧的基础。 帧填充装置向视频监视器连续地以显示帧速率向其生成图像样本的帧。
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