General Electric Company

James E Blake

Thomas W Lambert

Edward W Andrews

Robert R Lijewski

William H Wesbey

Jay S Plugge

James D Hajicek

Frank A Kozlowski

A method and apparatus for reducing delay times between successive x-ray images in a medical x-ray diagnostic system in which delay times are a function of the time required to transport film in a camera apparatus. The camera is used to record images on an image display apparatus. The delay time is reduced by determining the time at which an image on the apparatus will reach a predetermined intensity level and initiating the camera film transport cycle at a predetermined time prior to the image reaching the predetermined intensity level. Apparatus is disclosed for determining the rate of image development and for providing a signal to initiate the camera film transport at a fixed time prior to completion of image development regardless of the rate of image development. The predetermined time period is selected such that actual film motion is not initiated until the image is fully developed on the image display apparatus.

Exposure anticipation circuit

The display Gray level in a video display of a computer tomography system is changed at a rate which is non-linearly proportional to the rate of pulses generated by a manually operated control such as a track ball thereby accelerating change in the Gray level when a large change is desired and decelerating change in the Gray level when exact positioning is desired. Control of the rate of change can be by programmed computer or by hardwired logic.

Method and means for automatically variably controlling display

A composite video signal waveform is fed through a video mixer and to a video monitor for displaying a raster scanned image on its screen. Signals are also fed through the mixer for causing a cursor having distinctive light intensity to be overlayed on the image. Programs for defining multiple cursors are stored in a readable memory. A microprocessor uses the programs for generating cursor parameters for each horizontal raster line and these are stored in a random access memory. A direct memory access controller responds to occurrence of each horizontal sync pulse by loading the cursor parameters for each corresponding raster line into counters which determine the starting point and end point of the cursor in that line or the width of the particular cursor line. During the interval representative of cursor line width, signals are fed through the mixer for altering the brightness intensity of the display. The random access memory is read out on a horizontal line-by-horizontal line basis so as to produce a whole cursor configuration between vertical blanking intervals. Operator interactive controls are provided for moving and angulating cursors.

Cursor generator for use in computerized tomography and other image

Data derived from multiple x-ray views of a body layer is processed in accordance with an image reconstruction algorithm by a central processing unit (CPU) to result in a matrix of digital data corresponding with picture elements (pixels) which are for being displayed on a tv or video monitor. A device for delineating or identifying a region in the displayed picture with a box, irregular trace, or cursor with a bright dotted line uses a trackball to generate data signals corresponding in position with pixels in the matrix. The trackball generated data is processed for producing video picture modulating signals corresponding with the pixels in the matrix to which they positionally relate. The modulating signals are overlayed on the composite video signals from the display controller with a video mixer.

Device for delineating zones in a video image display

In computed tomography, a computer calculates CT numbers corresponding with the X-ray attenuation by elemental volumes in a body undergoing an X-ray beam scan. Analog signals corresponding with the sequence of CT numbers modulate a raster scanned cathode ray tube to produce a display of the image. Means are provided for controlling the display tube to display elements within a range of CT numbers or gray scale window. New means are provided for causing zones in the image corresponding with picture elements near the selected level or center of the gray scale to blink from gray to white such that when the level is set to correspond with a gray scale level of interest, the blinking zones will have CT numbers corresponding with the level setting. This permits identification of the CT numbers of the zones. The blink mode may be activated while the full image is displayed on the screen and zones of interest may be visualized in the total picture.

CT number identifier in a computed tomography system

Raster lines are obscured in a photograph of an image displayed on a video monitor. A photographic film is used as an integrating mechanism. The TV raster is vertically displaced during the camera shutter open time a total deflection of one horizontal line, thus blending the information between horizontal lines. Vertical raster deflection is accomplished by adding a series of delays to the normal vertical sync and then generating a processed composite sync to drive the external sync input to the monitor. The shutter is open for several video frames, each frame being deflected vertically by an integer amount greater than the previous frame until the total raster deflection equals one horizontal line.

Growing community of inventors

New Berlin, WI, United States of America

James E Blake