Abstract
Firstly, let's explain the basic principles of optical diffraction, which is the physical phenomenon where waves deviate from their original straight-line propagation when encountering obstacles. This experiment aims to investigate the varying degrees of wave bending after passing through narrow slits. This article mainly explores the relationship between the principal maximum value θ and the number of grating slits N.
In the experiment, we used the method of controlling variables to replace gratings with different numbers of slits while keeping the distance between the light screen, the grating, and the light source constant. We observed the imaging of light waves on the light screen and constructed a geometric model to calculate the value of the main maximum value θ using trigonometric function formulas.
First, we used the formula ∆θ=λ/Nd to calculate each preset value, then conducted actual measurements and recorded the data. Finally, combined with real experimental data, we verified that the formula ∆θ=λ/Nd holds true, and the principal maximum value θ is inversely proportional to the number of grating slits N.
摘要
首先，我们来解释一下光学衍射的基本原理，光学衍射是波在遇到障碍物时偏离其原始直线传播的物理现象。该实验旨在研究波浪在穿过狭窄狭缝后的不同程度的弯曲。本文主要探讨主极值θ与光栅狭缝数量N之间的关系。在实验中，我们采用控制变量的方法，在保持光幕、光栅和光源之间距离不变的情况下，用不同数量的狭缝替换光栅。我们观察了光波在光幕上的成像，并构建了几何模型，利用三角函数公式计算了主要最大值θ的值。首先，我们使用公式∆θ=λ/Nd）计算每个预设值，然后进行实际测量并记录数据。最后，结合真实实验数据，w .
Introduction
This experiment belongs to the exploration of the field of optics and is a diffraction experiment. Diffraction refers to the physical phenomenon where waves deviate from their original straight-line propagation when encountering obstacles. In classical physics, waves undergo varying degrees of bending propagation after passing through obstacles such as slits, small holes, or disks. If an obstacle is placed between the light source and the observation screen, bright and dark areas will appear on the observation screen, and the boundaries of these areas are not sharp, creating a complex pattern of alternating light and dark. This phenomenon is called diffraction and occurs when waves encounter obstacles along their propagation path.
Optical diffraction is a major research topic in modern science. The diffraction grating experiment is a type of optical experiment where the amplitude or phase (or both) of the incident light is periodically spatially modulated by a regular structure. The most important application of diffraction gratings in optics is as spectroscopic devices, often used in monochromators and spectrometers.
The main apparatus used in this experiment is the grating. A diffraction grating is a commonly used device in optical experiments that utilizes the phenomenon of light diffraction to achieve wavelength resolution. Diffraction gratings typically consist of a series of parallel and closely arranged grating strips. When parallel incident light passes through a diffraction grating, it is diffracted into a series of alternating light and dark fringes or spots.
The purpose of this study is to investigate the effect of adjusting the number of grating slits on the spectral width formed on the light screen, as well as the angular position of the principal maximum. By controlling variables such as the distance from the light source to the grating and the distance from the screen to the grating to be consistent, and using gratings with different numbers of slits, we ensure the accuracy and rigor of experimental measurements and summarize objective scientific laws.
This article first introduces the development background of diffraction grating technology, followed by the main problems and research objectives of this experiment. It briefly explains the research methods and experimental design, presents the experimental results and analysis reports, and finally summarizes the research conclusions and proposes future research directions.
简介
本实验属于光学领域的探索，属于衍射实验。衍射是指波在遇到障碍物时偏离其原始直线传播的物理现象。在经典物理学中，波在穿过狭缝、小孔或圆盘等障碍物后会经历不同程度的弯曲传播。如果在光源和观察屏之间放置障碍物，观察屏上会出现亮区和暗区，而这些区域的边界并不清晰，从而形成明暗交替的复杂图案。这种现象称为衍射，当波在其传播路径上遇到障碍物时就会发生。光学衍射是现代科学的一个重要研究课题。衍射光栅实验是一种光学实验，其中入射光的振幅或相位（或两者）通过规则的结构周期性地进行空间调制。
background
Diffraction and interference theory
Diffraction is a phenomenon in which a wave passes around an obstacle or slit, while interference is a phenomenon in which two or more columns of waves meet and superposition each other. In a grating, light is diffracted through multiple slits, and these diffracted waves interfere when they meet in space, creating an interference pattern between light and dark.
The grating equation describes the relationship between the diffraction Angle and the wavelength of light and the grating constant:
