Apparatus for and method of capturing radiation image

Abstract

A radiation application time upper limit calculator calculates a radiation application time upper limit based on a subject thickness, as measured by a subject thickness measuring unit. While an X-ray tube is controlled according to exposure conditions that have been set in order to apply a radiation X to a breast to capture a radiation image thereof, an X-ray tube controller compares the applied radiation time with the radiation application time upper limit. If the applied radiation time exceeds the radiation application time upper limit, then application of radiation to the subject is interrupted, so as to prevent an inappropriate radiation dosage from being applied to an X-ray detector.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a mammographic system according to an embodiment of the present invention;

FIG. 2 is a fragmentary vertical elevational view, partly in cross section, showing internal structural details of a radiation source housing unit of the mammographic system according to the embodiment of the present invention;

FIG. 3 is a fragmentary vertical elevational view, partly in cross section, showing internal structural details of an image capturing base of the mammographic system according to the embodiment of the present invention;

FIG. 4 is a block diagram of a control circuit of the mammographic system according to the embodiment of the present invention;

FIG. 5 is a flowchart of an operation sequence of the mammographic system according to the embodiment of the present invention; and

FIG. 6 is a block diagram of a control circuit of a mammographic system according to another embodiment of the present invention.

Claims

1. An apparatus for capturing a radiation image by emitting radiation from a radiation source and applying the radiation to a subject, comprising: required dosage setting means for setting a required radiation dosage required to capture the radiation image;radiation dosage upper limit setting means for setting a radiation dosage upper limit for the radiation applied to said subject;radiation application time upper limit setting means for setting a radiation application time upper limit until said radiation dosage upper limit is reached;radiation dosage detecting means for detecting a radiation dosage of said radiation applied to said subject; andradiation source control means for controlling said radiation source based on the radiation dosage of said radiation detected by said radiation dosage detecting means to apply the required radiation dosage of said radiation to said subject, monitoring a radiation application time in which said radiation is applied to said subject, and interrupting application of said radiation to said subject if the radiation application time exceeds said radiation application time upper limit.

2. An apparatus according to claim 1, wherein said radiation dosage upper limit setting means sets said radiation dosage upper limit based on image capturing information with respect to a region to be imaged of said subject.

3. An apparatus according to claim 1, wherein said radiation dosage upper limit setting means sets said radiation dosage upper limit based on image capturing information with respect to a thickness of a region to be imaged of said subject along a direction in which said radiation passes through said subject.

4. An apparatus according to claim 1, wherein said apparatus comprises a mammographic system.

5. An apparatus according to claim 1, further comprising: announcing means for announcing that said radiation source control means has controlled said radiation source to interrupt application of said radiation to said subject.

6. An apparatus for capturing a radiation image by emitting radiation from a radiation source and applying the radiation to a subject, comprising: radiation dosage upper limit setting means for setting a radiation dosage upper limit for the radiation applied to said subject;radiation dosage detecting means for detecting a radiation dosage of said radiation applied to said subject;required dosage setting means for setting a required radiation dosage required to capture the radiation image, based on said radiation dosage detected by said radiation dosage detecting means; andradiation source control means for controlling said radiation source based on the radiation dosage of said radiation detected by said radiation dosage detecting means to apply the required radiation dosage of said radiation to said subject, and canceling application of said radiation to said subject if said required radiation dosage exceeds said radiation dosage upper limit.

7. An apparatus according to claim 6, wherein said radiation dosage upper limit setting means sets said radiation dosage upper limit based on image capturing information with respect to a region to be imaged of said subject.

8. An apparatus according to claim 6, wherein said radiation dosage upper limit setting means sets said radiation dosage upper limit based on image capturing information with respect to a thickness of a region to be imaged of said subject along a direction in which said radiation passes through said subject.

9. An apparatus according to claim 6, wherein said apparatus comprises a mammographic system.

10. An apparatus according to claim 6, further comprising: announcing means for announcing that said radiation source control means has controlled said radiation source to cancel application of said radiation to said subject.

11. A method of capturing a radiation image by emitting radiation from a radiation source and applying the radiation to a subject, comprising the steps of: setting a required radiation dosage required to capture the radiation image;setting a radiation dosage upper limit for the radiation applied to said subject;setting a radiation application time upper limit until said radiation dosage upper limit is reached;detecting a radiation dosage of said radiation applied to said subject;controlling said radiation source based on the radiation dosage of said radiation and applying the required radiation dosage of said radiation to said subject to capture the radiation image; andmonitoring a radiation application time in which said radiation is applied to said subject and interrupting application of said radiation to said subject if the radiation application time exceeds said radiation application time upper limit.

12. A method according to claim 11, further comprising the step of: announcing an interrupted state when application of said radiation to said subject is interrupted.

13. A method of capturing a radiation image by emitting radiation from a radiation source and applying the radiation to a subject, comprising the steps of: setting a radiation dosage upper limit for the radiation applied to said subject;detecting a radiation dosage of said radiation applied to said subject;setting a required radiation dosage required to capture the radiation image, based on said radiation dosage;controlling said radiation source to cancel application of said radiation to said subject if said required radiation dosage exceeds said radiation dosage upper limit; andcontrolling said radiation source to apply the required radiation dosage of said radiation to said subject to capture a radiation image thereof, if said required radiation dosage does not exceed said radiation dosage upper limit.

14. A method according to claim 13, further comprising the step of: announcing a cancelled state when application of the radiation to said subject is cancelled.

15. A method according to claim 13, wherein said step of setting a required radiation dosage further comprises the step of: applying a dose of said radiation to said subject in an amount which is smaller than when said radiation image is captured.