《丁教授光学讲义.ppt

中学生物理冬令营－－光学 南京大学物理系 丁剑平 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 光是什么？ 光的基本特性 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 真空中的光速 c 例如 --- 空气：1.00029; 水：1.33; 玻璃 ~ 1.5 光的速度 －－普适常数 任何物体的运动速度不可能超过真空光速 c Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 正常色散曲线 折射率 n 与波长有关: Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 牛顿的色散实验 色散现象 正常色散曲线 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 光学的内容： 几何光学 波动光学（物理光学） 光与物质的相互作用 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 几何光学 用光线来处理光的传播 λ→0 几何光学三定律 光的直线传播定律 ---- 光在均匀媒质中沿直线传播 或者说，几何光学是波动光学的近似理论 反过来说，光在非均匀介质中的传播路径是曲线 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 反射线和折射线 在入射面内；（入射线、反射线、法线三者共面） 反射定律和折射定律： n1 n2 i1 i1’ i2 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 反射的特性 光路的可逆性：当光线沿反射光线方向入射时，反射光线一定沿入射光线方向反射 反射面可以是任意形状，光滑或粗糙，但每一条光线都遵从反射定律 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 例2、光线经过成 q 交角的两平面镜的两次反射后，出射光线跟入射光线的夹角 a 为多少？ B C D q M1 M2 解： O Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 例3.两个平面镜相互垂直放置，证明：不论入射光线方向如何，经过平面镜两次反射后的光线，总是与入射光线平行反向。 1