Multi-leaf collimator and multi-leaf collimator device

A multi-leaf collimator and multi-leaf collimator device; the multi-leaf collimator comprises at least one leaf group; the leaf group comprises a plurality of identical leaf pairs; each leaf in a leaf pair has a top surface, a bottom surface and two side surfaces located between the top surface and the bottom surface; the top surfaces of the plurality of leaves are arranged in a first circular arc having a radiating source as the center, and the bottom surfaces of the plurality of leaves are arranged in a second circular arc having the radiating source as the center, and the extension lines of both side surfaces of the plurality of leaves are focused at the radioactive source; the leaves in each leaf group are the same, so that the leaves in each leaf group are interchangeable, thus effectively reducing the types of leaves, facilitating in improving the controllability of leaf process precision and in the mass production of the leaves to reduce the cost of the multi-leaf collimator; the top surfaces and bottom surfaces of the plurality of leaves are arranged in circular arcs having the radiating source as the center, thus ensuring that the extension lines of both side surfaces of the plurality of identical leaves are focused at the radioactive source and have a smaller radiation field penumbra.