| 摘要 |
A collimator assembly of variable radiation field sizes and a radiation apparatus of the assembly. The radiation apparatus comprises a source carrier body, a collimator, and a collimator fixing bracket. The collimator is connected to the collimator fixing bracket via an arced guide rail having the center thereof running through a focus point and capable of rotating around the focus point. A radiation source and a precollimator are arranged on the source carrier body. Multiple sets of collimators are arranged on the collimator fixing bracket. Each collimator is provided thereon with multiple collimation openings forming different radiation field sizes on a focal plane. By combination of the different openings of the collimators to change the size of a radiation field, solved is the problem of forming radiation field sizes of different shapes on the focal plane and of intensity modulation of dose rate at the focus point. |
