Radiography
First Claim
1. Radiographic apparatus including a source of a substantially planar spread of penetrating radiation, such as X-radiation, detector means responsive to said radiation for detecting the radiation after it has passed through a body under examination, scanning means for scanning at least said source around the body about an axis intersecting said spread of radiation, means for causing relative movement to occur between said spread of radiation and said detector means, and collimator means including a plurality of apertured members, each including a respective part disposed between said body and the detector means, said parts being disposed so that they are successively encountered by said radiation, and means for moving said members at respective, different rates across said spread of radiation, said rates being influenced by the rate at which said scanning is executed, the rate of said relative movement and the proximity of the respective part to said detector means, whereby said apertured members as a whole act as a dynamic collimator arrangement for said detectors.
1 Assignment
0 Petitions
Accused Products
Abstract
In a computerized tomographic apparatus in which relative movement occurs between a fan of radiation and a bank of detectors, at least some of the detectors are required to receive radiation over a range of angles of incidence while at the same time being insensitive to scattered radiation. A dynamic collimating arrangement is described which enables each detector to accommodate said relative movement but nevertheless intercepts a substantial amount of scattered radiation.
-
Citations
10 Claims
- 1. Radiographic apparatus including a source of a substantially planar spread of penetrating radiation, such as X-radiation, detector means responsive to said radiation for detecting the radiation after it has passed through a body under examination, scanning means for scanning at least said source around the body about an axis intersecting said spread of radiation, means for causing relative movement to occur between said spread of radiation and said detector means, and collimator means including a plurality of apertured members, each including a respective part disposed between said body and the detector means, said parts being disposed so that they are successively encountered by said radiation, and means for moving said members at respective, different rates across said spread of radiation, said rates being influenced by the rate at which said scanning is executed, the rate of said relative movement and the proximity of the respective part to said detector means, whereby said apertured members as a whole act as a dynamic collimator arrangement for said detectors.
-
8. A medical radiological apparatus for examining a patient comprising:
-
a source disposed on one side of the patient and irradiating the patient with X-radiation fanning out substantially in a plane when moving downstream from the source; detectors of said radiation disposed in a row in said plane on the other side of the patient to receive and detect radiation from the source which has passed through the patient; means for orbiting at least the source around the patient and for moving the source relative to the detectors; and a dynamic collimator system comprising; a plurality of members each having a portion disposed downstream of the patient in the path of the radiation received by the detectors, each of said portions having X-ray transparent and X-ray opaque areas alternating in the direction in which the row of detectors extends; and means for moving at least said portions of the members, at respective different rates, relative to the radiation to align only X-ray transparent areas of the members along each of a numer of lines connecting the source with a corresponding number of detectors at selected relative positions of the source and detectors. - View Dependent Claims (9, 10)
-
Specification