Chapter 2Just Do It:Design a DigitalCamera Lens动手做：设计一个数码相机镜头In this chapter,you will design a fixed-focus digital camera lens for VGAresolution(640x480).在这章，你将会设计一个定焦数码相机镜头，它的显示绘图阵列分辨率是(640*480).Guided by the required specifications,youwill use the New Lens Wizard to identify a suitable starting point.根据说明书的指导，你将会使用新镜头向导去定义一个适宜的起点。You will thenmodify,analyze,and optimize the optical system to meet the requirements.后你将修改、分析、优化你的光学系统使它满足你的要求。This will allowyou to learn most of the basic techniques needed to use CODE V.这将使你学会使用CODE V的大部分基础技术。ContentsLearning by DoingThe New Lens Wizard....21Working with Surfaces.25CODE V Introductory User's Guide1Chapter 2 Just Do It:Design a Digital Camera LensLearning by DoingA Simple Digital Camera Lens一个简单的数码相机镜头Digital cameras are very common these days,and the latest mega-pixel models havehigh-esolution CCD arrays and sophisticated optics and electronics.数码相机在今天已相当普及了，最新的mega-piel有高分辨率的CCD阵列以及很成熟的光学和电子学。But don't worry,that won't be your very first task with CODE V.但这并不你学习CODE V的第一任务。Instead,you will design a fairly simple objective lensfor a fixed-focus digital camera.你将为定焦数码相机设计一个相对简单的物镜。This will still require some optical design,but it's a relatively simple problem,atwo-or three-element centered lens with glass and/or plastic refracting lens elements.这需要一些光学设计，但那只是相对简单的问题，一个两单元或三单元的由玻璃或塑料折射透镜单元组成的镜头。Here is what you will learn in this chapter:以下将是你这章所要学习的：？Interpret general design specifications for a simple lens给出你的镜头的大致设计说明Use this information to identify a starting point用这些信息来确定你的初模Modify the starting point to match the requirements修改你的设计初模使它符合你的要求Perform a basic analysis,compare these results with the specs,and determineguidelines for optimization执行基础分析，对比规格决定优化指导In the next chapter,you will use the results of this chapter as a starting point to章你将根据这一章的初模结果优化你的镜头Optimize the lenst优化镜头Identify problems with the design for potential refinement'它和镜头细微改进设计的问题有关These steps will allow you to work with many of CODE V's features through variousphases of optical design.在各个光学设计过程中将使你了解到CODE V里面的很多功能特点。We will explain some of these features as they are introduced here,withadditional explanations in subsequent chapters..我们将在这章引入这些功能，并将在下一章作进一步解释。Design Specifications设计说明Sometimes you will receive a lens prescription from someone and you will need toenter it in CODE V,analyze it,and perhaps optimize it.This is fairly straightforward.有时你将收到一些透镜库并把它载入CODE V,这是相当简单的。In other cases,a design problem starts out with a spec,or set of specifications,on how the lens2CODE V Introductory User's Guidemust perform,and from these guidelines you must determine a starting point,set itp,analyze,.and optimize it.在其他情况下，一个设计从它的初模的开始，说明书将告诉你要怎样操作的，这些你将从这些指导中决定选取哪个初模。For this digital camera problem,the spec came from a CODE V customer whomakes consumer products.The question was,"If you wanted to define a low-cost,fixed-focus digital camera for VGA,how would you specify it?"对于一个数码相机，它的规格来自CODE V的顾客，那些生产消费产品的人，也就是说“如果你要一个低造价、定焦的数码相机，那么你需要如何选择初模和设计”