教案光的等厚干涉与应用林一仙一 目的1、观察光的等厚干涉现象，加深理解干涉原理2、学习牛顿环干涉现象测定该装置中平凸透镜的曲率半径3、掌握读数显微镜的使用方法4、掌握逐差法处理数据的方法仪器读数显微镜，钠光灯，牛顿环装置二 原理牛顿环装置是一个曲率半径相当大的平凸透镜放在一平板玻璃上，这样两玻璃间形成空气薄层厚度e与薄层位置到中央接触点的距离r，凸透镜曲率半径R的关系为：(a)(b)图201根据干涉相消条件易得第K级暗纹的半径与波长入及牛顿环装置中平凸透镜的凸面曲率半径R存在下述关系：根据d2K与K成正比的性质采取逐差法处理实验数据教学内容和步骤1、牛顿环装置的调整，相应的提出问题，怎样将干涉图样调到装置的中心？2、显微镜的调节，焦距怎么调？叉丝怎样调节？干涉图样不清晰怎么办？反光镜怎么用？刻度尺怎么读？3、读数方法，要防止螺距差。读完一组之后要把牛顿环转90度再重新读一组。4、用逐差法处理数据，忽略仪器误差。三 注意事项1、仪器轻拿轻放，避免碰撞。2、镜头不可用手触摸，有灰尘时用擦镜纸轻轻拂去不能用力擦拭。调焦及调鼓轮时不可超出可调范围。为防止产生螺距误差，测量过程中鼓轮只能往一个方向转动，不许中途回倒鼓轮。六主要考核内容1、预习报告内容是否完整，原理图、公式、表格等是否无误。2、看是否将干涉图样调出来，数据是否有误等。七参考数据KdK(mm)dK（mm）（转90度）dK(mm)dK2(mm2)1027.3454.81527.2224.8224.81823.2122.53022.4001227.5415.21927.4355.2335.22627.3122.32222.2021427.7355.59027.6085.5985.59431.2922.14522.0101627.9075.94527.7955.9605.95235.4321.96221.8351828.0796.29127.9656.2976.29439.6121.78821.6682028.2356.60328.1256.6176.61043.6921.63221.5082228.3856.90528.2686.9136.90947.7321.48021.3552428.5317.19628.4157.2057.20051.8421.35521.2102628.6557.47028.5557.4837.47655.8921.19521.0722828.8057.73728.6857.7507.74459.9721.06820.9353028.9418.00628.8088.0038.00464.0620.93520.8053229.0628.25428.9408.2528.25368.1120.80820.688KdK(mm)dK（mm）（转90度）dK(mm)22dK(mm)1029.8059.79029.7409.9059.84896.9820.01519.8351230.23810.66330.19010.79510.729115.1119.57519.3951430.64811.47330.59511.60511.539133.1519.17518.9901631.02512.23030.96512.36312.296151.1918.79518.6021831.37512.93031.32513.07513.002169.0518.44518.2502031.70513.59031.66213.75413.672186.9218.11517.9082232.02514.23031.98514.40014.315204.9217.79517.5852432.32514.83732.28515.00014.918222.5617.48817.2852632.62815.43335.58515.60015.516240.7617.19516.9852832.90815.97832.86216.16716.072258.3216.93016.6953033.17816.53033.14816.73216.631276.5916.64816.4253233.43017.04233.41517.25017.146293.9816.38816.165