LEAF POSITION DETECTION DEVICE, MULTI-LEAF COLLIMATOR, AND RADIATION THERAPY DEVICE
A mark position detection unit includes an illumination unit which illuminates an identification mark provided on a leaf with detection light, and a detection unit which detects a light emitted from the identification mark which is illuminated with the detection light. The illumination unit includes a light source which emits the detection light. The detection unit includes a polarizing filter which filters the light emitted from the identification mark and an imaging device which detects a transmitted light filtered by the polarizing filter.
1 - 5 . (canceled)
6 . A leaf position detection device which detects a position of a leaf of a multi-leaf collimator having a plurality of leaves which limit a radiation field of radiation, the leaf position detection device comprising:
an illumination unit configured to illuminate an identification mark composed of a fluorescent substance provided on the leaf with detection light in a visible light range; and
a detection unit configured to detect light emitted from the identification mark which is illuminated with the detection light,
wherein the illumination unit includes a light source configured to emit the detection light, and
wherein the detection unit includes a polarizing filter configured to filter the light emitted from the identification mark and an imaging device configured to detect a transmitted light filtered by the polarizing filter.
7 . The leaf position detection device according to claim 6 , wherein the illumination unit further includes a polarizing plate configured to polarize the detection light emitted from the light source.
8 . A multi-leaf collimator which limits a radiation field of radiation, the multi-leaf collimator comprising:
a plurality of leaves arranged in a thickness direction of the leaf;
a driving mechanism configured to advance and retract each of the leaves with respect to the radiation;
an identification mark provided on each of the leaves and identifiable at least from a direction perpendicular to both the advancing and retracting direction in which the leaf is advanced and retracted and the thickness direction of the leaf; and
the leaf position detection device according to claim 6 .
9 . A radiation therapy device comprising:
the multi-leaf collimator according to claim 8 ;
a control unit configured to control the driving mechanism based on a position of the identification mark detected by the leaf position detection device; and
a radiation irradiation device configured to radiate radiation.