１设计原则：头颅Ｘ射线摄影检查位置繁多，铅板为Ｘ射线摄影检查常用器材，为使被检器官显示在同一张照片上，采用单纯铅板遮挡暗盒的一半，未遮挡部分曝光。有的一个部位要两侧对照分析，需投照４次。为有效地规范照射野面积，必须按被摄组织的大小，形态变更照射野。变... 1 design principles: skull X-ray examination of many locations, lead plate for the X-ray photography commonly used equipment, in order to make the organs were displayed on the same photo, the use of simple shielding half of the cassette, not part of the exposure block. Some sites to both sides of the control analysis, subject to vote 4 times. In order to regulate the irradiation field effectively, the irradiation field must be changed according to the size and shape of the tissue to be taken. change...