Estimation of the optical errors on the luminescence imaging of water for proton beam
Estimation of the optical errors on the luminescence imaging of water for proton beam
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DOI：
10.1016/j.nima.2018.01.030
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发表时间：
2018-04-21
影响因子：
1.4
通讯作者：
Yamamoto, Seiichi
中科院分区：
文献类型：
--
作者：
Yabe, Takuya;Komori, Masataka;Yamamoto, Seiichi
虽然质子束照射期间水的发光成像可以应用于距离估计，但发光图像的布拉格峰的高度小于用电离室测量的高度。我们假设这种差异的原因归因于光学现象；光学系统的视差误差和水体模的发光反射。我们估计了这些影响水的发光图像的光学现象引起的误差。为了估计发光图像的视差误差，我们通过改变相机光轴相对于布拉格峰的高度，使用冷却电荷耦合相机测量质子束照射期间的发光图像。当光轴的高度与布拉格峰的深度匹配时，深度剖面中的布拉格峰高度最高。黑墙幻影的水的发光反射略小于透明幻影的水的反射，并且改变了深度轮廓的形状。我们得出的结论是，视差误差显着影响布拉格峰的高度，并且体模的反射影响水的发光图像的深度剖面的形状。
Although luminescence imaging of water during proton-beam irradiation can be applied to range estimation, the height of the Bragg peak of the luminescence image was smaller than that measured with an ionization chamber. We hypothesized that the reasons of the difference were attributed to the optical phenomena; parallax errors of the optical system and the reflection of the luminescence from the water phantom. We estimated the errors cause by these optical phenomena affecting the luminescence image of water. To estimate the parallax error on the luminescence images, we measured the luminescence images during proton-beam irradiation using a cooled charge-coupled camera by changing the heights of the optical axis of the camera from those of the Bragg peak. When the heights of the optical axis matched to the depths of the Bragg peak, the Bragg peak heights in the depth profiles were the highest. The reflection of the luminescence of water with a black wall phantom was slightly smaller than that with a transparent phantom and changed the shapes of the depth profiles. We conclude that the parallax error significantly affects the heights of the Bragg peak and the reflection of the phantom affects the shapes of depth profiles of the luminescence images of water.