(a) Geometric scheme of the x-ray head and MLC components. Schematic drawings of the MLC from (b) the front and (c) the side.
Definition of pan and tilt coordinate system. (a) Pan rotation and (b) tilt rotation.
A custom-made jig for leaf position accuracy verification.
Leaf position accuracy testing film at the gantry angle of 90° with a pan rotational angle of 2.5°. The black dotted lines, perpendicular to match lines, show the leaf positions of −57.5, −27.5, 2.5, 32.5, and 62.5 mm. White dotted lines connected opposed small pinholes, indicating that the middle match line was parallel to the in-plane direction.
An example of dose profiles in the LR and HF directions for the maximum field size of .
A simplified geometric model with a tilt rotational angle of .
Intra- and interleaf leakage for the MLC for MHI-TM2000. (a) Leakage testing film. (b) Cross-leaf dose profiles along the dashed line in (a).
Tongue-and-groove effect on the MLC for MHI-TM2000. (a) Tongue-and-groove effect on testing film. (b) Cross-leaf dose profiles along the dashed line in (a).
Field characteristics without the pan and tilt rotations. Abbreviations: ; .
Field characteristics for nominal field size of at the maximum pan or tilt rotational angle of 2.5°. Abbreviations: ; .
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