工程光学英语补充内容和习题ppt课件

1、English SummaryEnglish Summary1. The electromagnetic spectrumGammaRaysX-RaysUltravioletV Infra-redMicro-wavesRadio-waveslongshortWave length380nmviolet-blue780nmdeep-red2. Law of Rectilinear propagationLight as it advances through free space or through homogeneous, isotropic matter follows a beeline

2、. (a direct straight course).Example: Shadows3. The Law of ReflectionA light ray striking a reflecting surface and reflected from it makes equal angles with the normal to the surface at the point of incidence, I=-Iand the incoming ray, the outgoing ray, and the normal to the surface at the point of

3、intersection all lie in the same plane.4. The Law of RefractionThe angle made by the incident ray, that made by the refracted ray, and the surface normal at the point of incidence in a refractive process obey the expression nsinI=nsinIThe incident ray, the refracted ray, and the surface normal are a

4、ll coplanar.5. Total Internal ReflectionnormalIncident rayRefracted rayDenser mediumRarer mediumCritical angleSurface6. Fermat principleLight takes the path that requires the least time.7. Key words and conceptImage space extends from infinity on one side to infinity on the other. The same holds for

5、 the object space; both completely overlap. Whether a given point is in the object space or the image space depends on whether it is part of a ray before or after refraction. If a given point is in the object space, it is a point object, otherwise it is a point image. Homework1. In ancient times the

6、 rectilinear propagation of light was used to measure the height of objects by comparing the length of their shadows with the length of the shadow of an object of known length. A staff 2m long when held erect casts a shadow 3.4 m long, while a buildings shadow is 170 m long. How tall is the building

7、? 2. Light from a water medium with n=1.33 is incident upon a water-glass interface at an angle of 45o . The glass index is 1.50. What angle does the light make with the normal in the glass?P12 4&9 Some Keywords1. single spherical surface2. converge and divergence3. conjugate ( points, planes, d

8、istance etc)4. magnification (transverse , axial , angular )5. Lagranges invariant6. sign convention (vertex, image distance, )7. image characteristics (larger or smaller, upright or inverted, real or virtual)8. Concave and convex mirror1. Vertex is the point where the optic axis intersects the surf

9、ace.2. Object distance is the distance from vertex to the object.3. Image distance is the distance from vertex to the image.4. Center of curvature is the center of single spherical surface.5. Meridional plane is a plane containing the optic axis and the object. Some ConceptHomework1. A goldfish swim

10、s 10cm from the side of a spherical bowl of water of radius 20cm. Where does the fish appear to be? Does it appear larger or smaller?2. An object is located 2cm to the left of convex end of a glass rod which has a radius of curvature of 1cm. The index of refraction of the glass is n=1.5. Find the im

11、age distance.P13-12&14 Some Keywords and concept1. Principal planes are defined as the loci where refraction is assumed to occur without reference as to where it actually does occur.2. Principal points are the points where the optical axis intersects principal planes. 3. Focal points (the first,

12、 the second / the object-side , the image-side )4. focal length is the distance from the principal point to the focal point.5. A on-axial point object at infinity and the second focal point are conjugate. Homework ( P18-Example) Some Keywords and concept1. Graphical construction HHFFFocal rayChief r

13、ayParallel rayThe parallel ray is first parallel to the axis and then, after refraction passes through F. The focal ray passes through F and then is rendered parallel to the axis.The chief ray goes through the principal point without deviation. Some Keywords and concept2. Newtons lens equation (x, x

14、 are called Newtons extrafocal object and image distances, respectively )3. Gauss equation Homework1. An object 1cm high is 30cm in front of a thin lens with a focal length of 10cm. Where is the image? Verify your answer by graphical construction of the image.2. A lens is known to have a focal lengt

15、h of 30cm in air. An object is placed 50cm to the left of the lens. Locate the image.P36-1&3 Keywords and concept1. Magnification Transverse magnification (Lateral magnification) is defined as the ratio of image size, y, to object size, y. Axial magnification (longitudinal magnification) is defi

16、ned as the ratio of a short length, or depth, in the image measured along the axis, to the conjugate length in the object. In the air, it is equal to the square of the transverse magnification.Angular magnification (magnifying power)The total magnification of a combination of lenses is the product o

17、f the magnification of the individual lenses. Keywords and concept2. Nodal points are where no refraction occurs. Whenever the refractive indices on either side of the lens are the same, the nodal points coincide with the principal points. If the refractive indices on the two sides of the lens are d

18、ifferent, the N points would move away from the principal planes, toward the side of higher index. Homework1. The object is a transparent cube, 4mm across, placed 60cm in front of a lens of 20cm focal length. Calculate the transverse and axial magnification and describe what the image looks like?P36

19、-4&6 Keywords and concept1. Plane mirrorwrong-readingIf a mirror is rotated through a given angle, a beam reflected by the mirror will be rotated through twice that angle. Keywords and concept2. Prisms are divided into two groups- reflecting prisms and dispersing prisms. 3. Some reflecting prism

20、s: right-angle prisms, roof (Porro) prisms, Dove (erecting) prisms, pentagonal prisms. Keywords and concept4. Dispersing prisms Elements of a prismApexApex angleAngle of deviationBasePrism equation Keywords and concept5. Dispersion Generally, the index decreases as the wavelength increases. The effe

21、ct is Chromatic dispersion Keywords and concept6. Optical material (glass, crystal, plastic) Crown glass (low dispersion)Flint glass (high dispersion) Keywords and concept7. Material characteristics Fraunhofer lines (blue F, yellow D, red C)Mean dispersion is numerical difference between the two ref

22、ractive indices nF and nC. Dispersive power Abbes number Keywords and concept1. Stops are either the finite size of the lenses or additional diaphragms in optical system which limit the bundle of light passing through in cross section. Keywords and concept2. Theory of stops3. An aperture stop is an

23、opening, usually circular, in an otherwise opaque screen. Keywords and concept4. The Aperture ratio of the system is the ratio D/f. Its reciprocal is f-stop number.5. Pupils (entrance pupil, exit pupil) Keywords and concept6. A field stop, in contrast to an aperture stop, limits the angular field, o

24、r field of view.7. Windows (entrance window, exit window)8. Telecentric on the object (image) side Homework1. A stop 8mm in diameter is placed halfway between an extended object and a large-diameter lens of 9cm focal length. The lens projects an image of the object onto a screen 14cm away. What is t

25、he diameter of the exit pupil?2. Two lenses, a lens of 12.5cm focal length and a minus lens of unknown power, are mounted coaxially and 8 cm apart. The system is afocal, that is light entering the system parallel at one side emerges parallel at the other. If a stop 15mm in diameter is placed halfway

26、 between the lenses:1) Where is the entrance pupil?2) Where is the exit pupil?3) What are their diameters? Homework Keywords and concept1. AberrationsMonochromatic aberrations (Spherical aberration, coma, astigmatism, curvature of field, distortion)Chromatic aberrations Keywords and concept2. Monoch

27、romatic aberrations can be further divided into two groups depending on whether or not they cause the image blur. Image blur occurs in spherical aberration, coma and oblique astigmatism. Keywords and conceptCurvature of field and distortion cause dislocations within the image but no blur.3. Wave abe

28、rration: The degree of departure from true sphericity,that is, the distance between the ideal reference sphere and the actual, distorted wavefront, measured along the radius of the reference sphere. Keywords and concept HomeworkAnswer the following questions:1. What is an aberration? How does it com

29、e?2. How can we classify the aberration?3. What is wave aberration? What relationship among wave aberration and other aberrations? HomeworkReading the complementary information and fill in the following form: Homework Answer1. What is an aberration? How does it come?An aberration is the difference b

30、etween the real image and the ideal image.In paraxial-ray tracing, which we discussed earlier in conjunction with single surfaces and thin lenses, we had assumed that the angles which the rays subtend with the optic axis aresmall. If this is so, the sines of these angles can be set equal to the angl

31、es themselves( in radians). In fact, the angles are larger, and if we use exact ray tracing, this can no longer be done. The sine of an angle must then be represented by a series expansion. So the difference occurs. Homework Answer Homework Answer2. How can we classify the aberration?AberrationWave

32、aberrationGeometrical aberrationChromatic aberrationMonochromatic aberrationSpherical aberrationComaAstigmatismCurvature of fieldDistortion Homework Answer3. What is wave aberration? What relationship among wave aberration and other aberrations?The degree of departure from true sphericity,that is, t

33、he distance between the ideal reference sphere and the actual, distorted wavefront, measured along the radius of the reference sphere.Generally speaking, the larger geometrical aberration is, the larger wave aberration is. Spherical aberration,coma, and astigmatism all have characteristic wavefront

34、distortions. In curvature of field and distortion, the wavefront normals come together but at the wrong point. Homework Answer Homework answerFill in the following form:A person wants to look at the image of his or her own eyes, without accommodation, using a concave mirror of 60cm radius of curvatu

35、re. How far must the mirror be from the eye if the person has1) Normal vision?2) 4diopter myopia, without correction?3) 4diopter hyperopia, without correction? Homework Keywords and concept1. Cross section of the human eye Keywords and concept2. Reduced eye and schematic eye3. Accommodation is accom

36、plished by a changed of power of the lens, resulting from a change of shape. Keywords and concept4. Normal vision5. Anomalies Myopia (nearsightedness)Hyperopia (hypermatropia, farsightedness) HomeworkA person wants to look at the image of his or her own eyes, without accommodation, using a concave m

37、irror of 60cm radius of curvature. How far must the mirror be from the eye if the person has1) Normal vision?2) 4diopter myopia, without correction?3) 4diopter hyperopia, without correction?P140-1&2 Keywords and concept1. MicroscopeA microscope is an instrument for viewing objects that are very

38、small.It is a two lens system, an objective of short focal length and an eyepiece.The distance between the right-hand focus of the objective and the left-hand focus of the eyepiece is called the optical tube length. Keywords and concept2. The structure of a microscope Keywords and concept3. Numerica

39、l aperture, NA4. The distance of most distinct vision, 25cm in front of the eye. Keywords and concept5. TelescopeKeplers telescope contains two converging lenses: an objective of long focal length and an eyepiece of short focal length. The lenses are spaced so that the second focus of the first lens

40、 coincides with the first focus of the second lens. Keywords and conceptGalileos telescope contains two lenses: the objective is positive and the eyepiece is negative. Still the two focal points coincide.The image is seen at infinity, with accommodation, the image is seen at the distance of most dis

41、tinct vision. Instrument myopia is a phenomenon that a person involuntarily accommodates when he or she looks into an optical instrument. Keywords and concept HomeworkDiscussion:What differences between the following situations: 1) a microscope is used for projection;2) the microscope is used for vi

42、sual observation.P140-3&6 Supplementary materials1. Digital cameraA/DMPU内存内存LCDPC卡卡接口接口成像物镜成像物镜CCD数码相机的成像过程数码相机的成像过程任务原理颜色的构成分色棱镜覆盖转轮目的像素数颜色深度 Supplementary materialsR G R G R G R GG B G B G B G BR G R G R G R GG B G B G B G BR G R G R G R GG B G B G B G BR G R G R G R GG B G B G B G BR G B G B

43、G B GG R G B G R G BR G B G R G B GG R G B G R G BR G B G R G B GG R G B G R G BR G B G R G B GG R G B G R G BBAYER编码三色编码 HomeworkClassification of camera lenses:1)Tessar camera lens (most widely used) 2) Telephoto lens3) Wide-angle lens, fisheye lens ,sky lens4) A zoom lensP140-5&7 Brief histor

44、y of laserThe word LASER is an acronym for light amplification by stimulated emission of radiation. In 1916, Einstein predicted that the existence of equilibrium between matter and electromagnetic radiation required that besides emission and absorption there must be a third process, now called stimu

45、lated emission.This prediction attracted little attention until 1954, when Townes and coworkers developed a microwave amplifier (Maser) .In 1958, Schawlow and Townes showed that the maser principle could be extended into the visible region.In 1960, Maiman built the first laser using ruby as the active medium. Brief history of laserCompared to radiation from other sources, laser radiation stands out in several ways. It has a particular beam sh