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目的研究利用射野影像系统进行出射剂量测量的可能性。以便能进一步把该类系统发展为剂量仪系统。材料与方法使用荧光型电子射野影像系统，探头由金属板—荧光屏和Ｐｌｕｍｂｉｃｏｎ照像机组成。通过与电离室及射野证实片所测结果的比较，建立一套与像素位置对应的灰度校正矩阵。并在多种射野面积和体模厚度下验证，所用射线为６ＭＶ－Ｘ线。结果通过对该系统的各种性能测试，如灰度的稳定性、探头的均匀性、剂量响应曲线、灰度的射野依赖性及对体模厚度的依赖性，发现短期稳定性好于１％，有较明显的灰度饱和性，但需作灰度饱和校正。作为相对剂量仪使用时，只要建立一个探头非均匀性校正矩阵，就能与证实片的剂量结果保持一致，误差小于±５％。结论研究证明，电子射野影像系统完全可以成为一套剂量仪系统。在对靶区的位置进行实时监测的同时，还能通过对影像灰度的计算，得出出射野的剂量分布
Objective To study the possibility of using the field imaging system to measure the outgoing dose. In order to further develop this type of system into a dosimeter system. Materials and Methods Fluorescence electronic imaging system was used. The probe consisted of a metal plate - a phosphor screen and a Plumbicon camera. By comparing with the measured results of ionization chamber and field confirmed film, a set of gray level correction matrix corresponding to the pixel position is established. And in a variety of field area and phantom thickness verification, the radiation used for the 6MV-X line. Results The short-term stability was found to be better than 1 by testing various performance tests of the system, such as the stability of the grayscale, the uniformity of the probe, the dose response curve, the dependence of grayscale dependence on the thickness of the phantom %, There is more obvious gray saturation, but for saturation correction. When used as a relative dosimeter, the establishment of a probe non-uniformity correction matrix can be consistent with the dose results of the certified tablets with an accuracy of less than ± 5%. Conclusions Research has shown that electronic field imaging systems can be a complete dosimeter system. In the real-time monitoring of the location of the target area, but also through the calculation of the image gray, the dose distribution of the outgoing field