Multi-blade collimator blade zero calibration device

Abstract

The invention discloses a multi-blade collimator blade zero calibration device. The device comprises a photoelectric switch assembly, a light path collimation assembly, a blade assembly and a blade driving control assembly which are installed on a multi-blade collimator base. The photoelectric switch assembly is used for forming a detection light beam and feeding back a calibration signal to the driving control assembly; the light path collimation assembly is used for ensuring that the divergence error of the detection light beam in the detection range meets the positioning precision requirement; and a plurality of blades in the blade assembly are respectively driven by the blade driving control assembly to move to the detection light beam for zero calibration. According to the invention, the optical path of one photoelectric switch is segmented and collimated through the light path collimation assembly, trigger errors of different positions of the optical path of the photoelectric switch caused by long-distance transmission scattering are eliminated, the zero consistency of each blade of a multi-leaf collimator is improved, and zero errors caused by inconsistency of the trigger precision and attenuation speed of multiple photoelectric switches are eliminated at the same time.

Description

technical field [0001] The invention relates to the technical field of radiotherapy instruments, in particular to a blade zero position calibration device of a multi-leaf collimator. Background technique [0002] According to the projection shape of the tumor under a certain radiation angle, the multi-leaf collimator forms a polygon close to the projection shape of the tumor through the movement of multiple leaves, so as to complete the conformal radiation therapy. The position of the leaves and the consistency of repeatability have a great influence on the accuracy of radiotherapy. Usually, multiple photoelectric switches are used to calibrate the zero positions of multiple leaves, and then the position of each leaf is sampled through the photoelectric encoder, which increases the number of photoelectric switches. The position sampling consistency error, and the inconsistency of the precision and attenuation speed of each photoelectric switch also introduce positioning erro...

AI Technical Summary

Problems solved by technology

The position of the leaves and the consistency of repeatability have a great influence on the accuracy of radiotherapy. Usually, multiple photoelectric switches are used to calibrate the zero positions of multiple leaves, and then the position of each leaf is sampled through the photoelectric encoder, which increases the number of photoelectric switches. The position sampling consistency error, and the inconsistency of the precision and attenuation speed of each photoelectric switch also introduces positioning errors

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