近几年各地中考中有关光学的暗箱题很多,解题时不少学生出错,例如下面一题:在图1所示的方框中画出一个合适的光学元件,并完成光路图.图1　　　　　　　图2有些学生认为:方框前是会聚光线,经框内光学元件后成平行光线,于是就相当然地画上了一个凹透镜,如图2所示.此答案是错... In recent years, there have been a lot of questions about optics in the middle school entrance exams, and many students have made mistakes when solving the questions. For example, the following question: draw a suitable optical component in the box shown in Figure 1, and complete the light path diagram. Figure 1 Figure 2 Some students think that: Before the box is the convergence of light, after the optical elements within the frame into a parallel light, so it is natural to draw a concave lens, as shown in Figure 2. This answer is wrong...