X-ray or gamma ray systems or devices – Beam control – Filter
Patent
1983-06-06
1985-01-29
Smith, Alfred E.
X-ray or gamma ray systems or devices
Beam control
Filter
378 62, G03B 4116, H05G 300
Patent
active
044970625
ABSTRACT:
X-ray compensation masks (51) are prepared by exposing an X-ray target object (43), such as a patient, to a first beam of X-rays. The X-ray fluence from the patient is received by an electronic image receptor (44) which provides an output signal indicating the intensity of the X-rays at all positions in the image field. The image information is converted by an image processor (47) to transformed X-ray intensity values for a plurality of pixels which cover the image field. A mask generating controller (48) determines the minimum transformed intensity value for any pixel, assigns to each pixel an attenuation number which is proportional to the difference between the transformed intensity value for the pixel and the minimum transformed intensity value, and issues control signals to a mask former (49) which deposits on a non-attenuating substrate (50) attenuating masses in a two dimensional array of pixels with the mass thickness in each pixel proportional to the attenuation number. When the mask (51) is inserted into the beam from the X-ray source (41), and a second exposure taken, the X-ray fluence passing through both the attenuating mask (51) and the patient (43) will be substantially equalized across the image field.
REFERENCES:
patent: 2216326 (1940-10-01), Smith
patent: 2744031 (1956-05-01), Mumma
patent: 3074801 (1963-01-01), Gessler et al.
patent: 3248547 (1966-04-01), Van DeGeijn
patent: 3486006 (1969-12-01), Siegel
patent: 3717768 (1973-02-01), Edholm et al.
patent: 3748487 (1973-07-01), Edholm et al.
patent: 3755672 (1973-08-01), Edholm et al.
patent: 3917954 (1975-11-01), Boge
patent: 3921001 (1975-11-01), Edholm et al.
patent: 3961121 (1976-06-01), Warsager
patent: 4322619 (1982-03-01), Nelson
patent: 4347440 (1982-08-01), Haas
R. A. Kruger et al., "A Digital Video Image Processor for Real-Time X-Ray Subtraction Imaging," Optical Engineering, vol. 17, No. 6, Nov.-Dec. 1978, pp. 652-657.
D. B. Plewes et al., "Improved Lung Nodule Detection with an Equalized Image," SPIE, vol. 233, Application of Optical Instrumentation in Medicine VIII, 1980, pp. 183-189.
E. C. Pennington et al., "High Bandpass Spatial Filtering of the Primary X-Ray Beam," SPIE, vol. 233, Application of Optical Instrumentation in Medicine VIII, 1980, pp. 176-182.
L. Kusoffsky et al., "Attenuation Equalizing Filter in Diagnostic Radiography," Acta Radiologica Therapy Physics Biology 15, Jun. 1976, pp. 259-272.
Paul R. Edholm et al., "Primary X-Ray Dodging," Radiology, vol. 99, Jun. 1971, pp. 694-696.
"Digitally Controlled Beam Attenuator", Proceedings of SPIE, vol. 347, pp. 106-111.
Dobbins, III James T.
Hasegawa Bruce H.
Kudva Balakrishna V.
Mistretta Charles A.
Peppler Walter W.
Grigsby T. N.
Smith Alfred E.
Wisconsin Alumni Research Foundation
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