1、专业英语教案 光电信息工程专业用专 业 英 语 教 案1 What is Optics（什么是光）Mankind has always been fascinated with light, thinking of it in ancient times as an uncontrollable, mystical force of nature. Science unraveled some of its mysteries as the inventions of mirrors, spectacles, and later microscopes and telescopes revea
2、led to mankind how light can be tailored to help people in their daily lives and in exploration, physically through the world and intellectually through science. unraveled vt. 阐明, 解决 reveal vt. 展现, 显示, 揭示, 暴露 tailor n. 裁缝；vt. 剪裁, 缝制(衣服), 适应, 适合人类总被光迷住，在古代把它认为成是一种无法控制的、神秘的自然力量。科学用一些发明来阐明光的神秘，例如有镜子，眼镜
3、和后来展示给人类的显微镜和望远镜，以此来告诉我们光是如何被调整而用于帮助人们的日常生活和科学研究，以及帮助我们认识世界和发展科学（身体上通过世界和智力通过科学）。Optics is the study of light and vision in science and engineering. Light is generally defined as the sector of the electromagnetic spectrum between the infrared and ultraviolet sectors that can be seen with the unaided
4、 eye.光学是在科学和工程方面对光和视觉的研究。光一般被定义介于红外和紫外之间、可被裸眼看到的电磁波谱的一部分。Optics plays an influential role in our lives:光学在我们的生活中起着重要作用：When you look into a mirror in the morning to comb your hair, when you see a rainbow after it rains, in medical devices that save lives, as you read this page, as you see, optics is
5、 at work.当你在早晨面对一面镜子梳你的头发时，当你在雨后看到彩虹时，在那些挽救生命的医学设备里，当你读这篇文章时，如你所见，是光在工作。Through these lessons, we hope to give you at least a peek peek vi. 偷看；窥视；偷偷的一看, 一瞥我们希望通过下面的这些课程，可以使你对光学有个大概的了解：into geometrical optics; geometrical adj. 几何学的, 几何的对几何光学into physical optics; 对物理光学into the dual nature of light and
6、 past and current theories on it; 光学在过去和现代理论中的二重性into lenses and mirrors; 对透镜和反射镜into optical instruments; 对光学仪器into experiments that led to breakthroughs in the study of optics; breakthrough n. 突破；突破性的发现，成就对在光学的研究过程中带来突破的实验；into how optics affects our daily lives and how it will affect the future.光
7、学是如何影响我们现在的日常生活，以及将如何影响未来。2 The Dual Nature of Light（光的二重性）The nature of light has been a controversy debated throughout the course of history. Two models evolved: the wave model and the particle model. Each model has taken an important dominating place, but neither has been disproved completely. Th
8、erefore, the scientific community has combined the two theories to form the wave particle duality, where characteristics from both models are attributed to light (the “wavicle”). These two seemingly contradicting models have been reconciled by a new theory of physics, called quantum electrodynamics,
9、 which is a quantum theory of the electromagnetic interactions between photons, electrons and muons (an elementary particle having a mass around 200 times greater than an electron). This model is also known as quantum theory of light. controversy n. 争论, 辩论, 论战； debate v. 争论, 辩论 dominating adj. 专横的,
10、主要的, 独裁的 disprove vt. 反证；反驳；证明为伪 wavicle 物量子波粒二象性 attribute vt. （与to连用）归因于 contradict vt. 同矛盾, 同抵触 reconcile vt. 使和解, 使和谐, 使顺从；调解, 调停; 使相协调 quantum electrodynamics n. 物量子电动力学 electromagnetic interaction 电磁相互作用 muon n. 介子 elementary particle n. 核基本粒子光的本性在其整个历史过程中是一场辩论。它们发展成两种模式：波动模型和粒子模型。每一种模型都有其重要的专
11、用位置，但是没有任何一个可以被完全证明为误。因此，科学界将这两种理论结合而形成波粒二象性，而来自于两种模型的特征可以归因于光（波粒二象性）。这两种看似矛盾的模型被一种新的物理理论所统一，即量子电动力学，是一种光子，电子和介子（某一体积比单个电子大大约200倍的基本粒子）之间的电磁相互作用的量子理论。这个模型也被称为光的量子理论。The Wave Theory of Light:光的波动理论The theory that light is transmitted via wave form was proposed by Christian Huygens in 1679. According
12、to his theory:光以波动形式传播的理论是克里斯蒂安惠更斯在1679年提出的，根据他的理论：（克里斯蒂安惠更斯：（Christian Huygens 1629-1695）是与牛顿同一时代的科学家，是历史上最着名的物理学家之一，他对力学的发展和光学的研究都有杰出的贡献，在数学和天文学方面也有卓越的成就，是近代自然科学的一位重要开拓者。） Light must travel through a medium. 光必须通过某种介质进行传播。 This medium is called Ether, which is an omnipresent, boundlessly resilient
13、, massless medium unable to be sensed that was formerly theorized as the medium that carried light. 这种介质称为以太，它是一种无所不在的，有无限弹性的，无质量的，不不能被感知的介质，在从前它被理论化为能运载光的介质。 Light is a form of energy - Light travels in waveform in short wavelengths. 光是一种能量形式光在短波长方面以波形的形式传播。 ether n. 天空醚, 大气, 苍天, 物以太 omnipresent ad
14、j. 无所不在的, 同时遍在的 boundlessly adv. 无穷地, 无限地 resilient adj. 弹回的, 有回弹力的 massless adj. 物无质量的 theorize v. 建立理论, 理论化 waveform n. 波形The Particle Theory of Light:光的粒子理论The theory that light is transmitted via corpuscular form was supported and advocated by Sir Isaac Newton. According to this theory: light is
15、 composed of particles (“corpuscular”) that travel in a straight line at an extreme speed, they allow the eye experience vision when they are absorbed, and various colored particles all have differing sizes. corpuscular adj. 微粒的，细胞的，小体的 advocate vt. 拥护；提倡； 主张 according to v. 依照光以粒子形式传播的这一理论被艾萨克牛顿先生支
16、持并且提倡。依照这一理论：光是由粒子构成的，它们沿直线并以高速传播，当它们被吸收时，就使得眼睛体验视力，不同颜色的粒子都有着不同的尺寸。The Quantum Theory of Light:光的量子理论The theory that combines both the wave and particle models was suggested by Max Planck. According to this theory: light is absorbed or released in bundles of energy called photons. suggest vt. 建议, 提
17、出, 使想起, 暗示结合波动模型和粒子模型的理论是由马克斯普朗克提出的。依照这一理论：光被以含有能量束的光子形式吸收或者释放。Huygens Principle:惠更斯原理Christian Huygens, a Dutch scientist, supported the concept that light is a wave motion that is transmitted through ether. Applying this theory, Huygens derived the laws of reflection and refraction. derive vt. 获得,
18、 导出(from)克里斯蒂安惠更斯，一位荷兰科学家，他支持光是通过以太传播的波形运动的概念。应用这一理论，惠更斯推导出反射定律和折射定律。Youngs Double-Slit Experiment:杨氏双缝实验Thomas Young (1773-1829), an English scientist, also credited for helping translate the Rosetta Stone, conducted an experiment in 1801, known as Youngs double-slit experiment, that allowed him to
19、 show the wave nature of light and measure its wavelengths. The setup of this experiment is quite elegant-Light from a single source shines through two narrow, closely-placed slits for them to serve as two coherent light sources. (A coherent light source is one that makes light waves have a consiste
20、nt phase relationship with each other-crest overlaps crest, trough overlaps trough) A screen is put behind these slits. credit n. 信任, 信用, 声望, 荣誉, 财务贷方, 银行存款vt. 相信, 信任, 把.归给 conduct vt. 处理； 经营；引导；实施 elegant adj. 优雅的, 风雅的, 雅致的, 文雅的, 有风度的；优美的, 精彩的, 讲究的 crest 【物】波峰; 振幅; 峰值, 最大值 trough 【物】波谷托马斯杨(1773-182
21、9)，一位英国科学家，也相信可以帮助翻译“罗塞塔碑”，在1801年进行了一个实验，就是着名的“杨氏双缝实验”，这一实验使得他向人们展示了光的波动特性，并且可以测量波长。这个实验的安装十分讲究来自同一光源的光将两条狭窄、挨得很近的裂缝照亮，那么它们就象两个相干光源（相干光源是指能够使得两束光相互有固定的位相关系，波峰与波峰重叠，波谷与波谷重叠）。（约5000年前，古埃及人发明了一种图形文字，称为象形文字。这种字写起来既慢又很难看懂，国此大约在3400年前，埃及人又演化一种写得较快并且较易使用的字体。随着时光的流逝，最终连埃及人自己也忘记了如何释讳早期的那种象形文字了。若不是因为拿破仑大军入侵埃及
22、时，随军的法国古文字学家们的那次发现，极有可能至今考古学家们仍无法辩认这种文字。年，拿破仑率军远征埃及时，他手下的一名军官布夏尔带领士兵，在罗塞塔城附近修筑防御工事时，发现了一块黑色玄武岩断碑。碑上用两种文字三种字体刻着同一篇碑文。最上面用的是古埃及的象形文字，中间是古埃及的草书体象形文字（亦称民书体文字），下面是希腊文字。这就是后来被世人称之为“罗塞塔碑”的着名石碑。原来，“罗塞塔碑”上的碑文是公元前年埃及孟斐斯城的僧侣们，给当时的国王写的一封歌功颂德的感激信。这位国王就是第十五王朝法老托勒密。他登上国王宝座后不久，取消了僧侣们欠交的税款，并为神庙开辟了新的财源，对神庙采取了特殊的保护措施，
23、给僧侣们带来了一系列好处，所以很快赢得了僧侣们的敬仰。于是僧侣们写了这封感激信，并用三种字体写的两种文字刻在这块黑色玄武岩碑石上。小小的罗塞塔城，由于有了这块借以解开埃及象形文字之谜的碑石而举世闻名。不过，这块着名的碑石早已不在该城，它被收藏在伦敦的大英博物馆里了。）Now, if light consisted of particles, then the screen would reveal two bright lines when the light illuminated through. Young, however, saw a center bright line and g
24、roups of symmetrical dark and bright edges and explained these groups to be marks of constructive and destructive interference. constructive interference 相长干涉（当两列同相的波相遇，它们的波峰波谷会叠加成一个更大的波峰波谷，这现象称为相长干涉。） destructive interference 相消干涉（当两列反相的波相遇，一列波的波峰会叠加在另一列波的波谷上，使两个波互相抵消，这现象称为相消干涉。）那么，若光由粒子组成，当光通过狭缝时，
25、在屏幕上将显示两条明亮的线。不过，（托马斯）杨看见中心是亮线，然后两侧是对称的明暗边缘，并且解释这些条纹就标志着相长干涉和相消干涉。So, since weve covered the basics, here is a diagram, which geometrically analyzes the experiment and explains some equations:因此，既然掌握了这些基本性质，这就是一张图解，可以从几何角度分析这些实验并且解释一些方程式：As the image indicates, the difference in the length of and is
26、 .正如图像所显示的，和的长度差为。Equations for Youngs Double-Slit Experiment may be found here. 杨氏双缝实验的公式在这里就可以得到。Fresnel and Transverse Waves:Augustin Fresnel, in 1821 put forward results from experiments involving double refraction and polarized light suggested that light is a transverse wave, which is a wave wh
27、ere the vibrating part moves perpendicularly to the coming wave. Equations that he formulated, the Fresnel equations provide the amplitude of reflected and transmitted polarized light traveling at a plane interface. Transverse adj. 横向的, 横断的 formulate vt. 用公式表示, 明确地表达, 作简洁陈述；v. 阐明 amplitude n. 【物】振幅
28、interface n. 分界面奥古斯丁菲涅耳，在1821根据双折射和偏振光方面的实验提出结论，认为光是一个横波，所谓横波是指波的振动方向与传播方向垂直（原文：波的振动部分垂直地移向来波）。他推导出的方程式称为菲涅耳方程式，当光遇到一个平面的分界面时，它可以给出反射光和透射偏振光的振幅。Further Developments:James Clerk Maxwell, a scientist studying electricity and magnetism, formulated the four Maxwell equations, which gave a predicted spee
29、d of an electromagnetic wave through ether, which actually ended up being the speed of light, c. So from this point on, light was considered to be a part of the electromagnetic spectrum. Predict v. 预知, 预言, 预报, 预测 end up v. 竖着, 结束, 死詹姆斯克拉克麦克斯韦，一位研究电学和磁学（电磁学）方面的科学家，总结出4个麦克斯韦方程式，这一方程组可以给出电磁波在以太中的预测速度，这
30、实际上是给出了光速c。因此自此以后，光被认为是电磁波谱的一部分。And later still, Einsteins theory of relatively helped throw out the idea of ether, which solved some problems dealing with the transverse vibrations of waves in liquids and gases. throw out v. 伸出, 扔掉, 说出, 派出, 放出, 使出局, 使突出, 显示并且直至后来，爱因斯坦的相对论帮助（我们）丢弃以太的概念，这就可以解决在液体和气体中
31、横波遭遇的一些（无法解决的）问题。3 Geometrical Optics（几何光学）Lets face it. Optics is pretty complicated. Light travels in waves, and waves are not easy to analyze. Thats why in this lesson we are going to try to explain as many phenomena of reflection and refraction as possible with only straight lines and angles ins
32、tead of waves to represent light. 让我们面对它。光学相当错综复杂。光以波的形式传播，而波也不容易分析。那也就是为什么在这门课中，我们将尽可能多地只用直线和角度而非波来描述反射和折射现象。Before we begin, an important concept to note is the speed of light, or .在我们开始之前，需要要注意到的一个重要的概念，那就是光的速度，或者叫。Now that you know the speed of light in meters per second, you will be able to apply it to
