同学们学习每一单元内容后若能将其作一系统的归纳总结，则对加深理解与记忆大有益处．初中物理光学知识可归纳为“（六）2（四）3”：（－）2个模型：光源与光线．光源是指能够自行发光的物体，光源是物体，但物体不一定是光源；光线是指光的传播路线，在同一介质里光线是直的 After students learn each unit content, if they can summarize it systematically, it will be helpful to deepen understanding and memory. Junior high school physical optics knowledge can be summarized as “(six) 2 (four) 3”: (-) 2 models: light source and light. Light source refers to an object that can emit light by itself. A light source is an object, but an object is not necessarily a light source. Light refers to the propagation path of light. In the same medium, light is straight.