视光专业英语大作业

材料专业英语大作业班级11视光（2）班姓名徐天平学号1107102061成绩1040-5488/07/8407-0548/0 VOL. 84, NO. 7, PP. 548–549 OPTOMETRY AND VISION SCIENCECopyright © 2007 American Academy of OptometryBOOK REVIEWAdaptive Optics inVision ScienceJason Porter,Hope Queener,Julianna Lin,Karen Thorn,Abdul Awwal,eds. Hoboken,NJ WileyInterscience;2006.$150.00.The last decade has been a remarkably productive and interesting time for those vision scientists who study the retinal structure of the human eye. In great part this has been made possible by the introduction of a technological advance in their field that has dramatically increased their ability to resolve the fine detail of the retina. This advance is the incorporation of adaptive optics into their imaging systems and by so doing, to almost completely remove the natural optical aberrations of the eye. Those involved in this field are comparatively few in number, and there are a limited number of centers throughout the world equipped to conduct this research. However, there is great interest in their findings throughout the large field of vision scientists and eye care professionals. So, a number of pioneers in the field of adaptive optics for vision science thought to put together a book “to equip engineers, scientists, and clinicians with the basic concepts, engineering tools, and tricks of the trade required to master adaptive optics-related application in vision science and ophthalmology.”Adaptive Optics inVision Science is the result of this initiative.Does the book fulfill its stated goal? I think it only partially does and I will say why I feel this way. However, this book is valuable in a way the authors themselves perhaps did not perceive, in that is represents a unique historical record of the thoughts and opinions of the pioneers and early workers in a field that has most recently experienced a revolution. Each chapter of the book has been written by people who participated in this revolution, each in their own way and at their respective institutions. So in reading what they have written about their work, one gets a glimpse of the different approaches and ideas one always finds in any field that is new and emerging. Later in its life a scientificfield develops an ‘orthodox’ view, but in the beginning many views exist together and what way better to record them than to get those involved at the beginning to write about what they consider to be important parts of their work? Scientists may like to feel that their work is quite objective in nature but in fact, subjective opinion and human preference are as present in science as in any field of human endeavor. This is why it is so interesting to read the work of early workers in any field because then you see the variety that is often suppressed as a field matures and the opinions of a few start to dominate. Adaptive Optics in Vision Science offers this interesting window into the early days of an exciting new scientific field.Now let us see what the reader will find in this book. Each chapter in the book is written by persons associated with one of the active centers doing vision research with a system using adaptive optics. These centers are the University of Rochester Center for Adaptive Optics (six chapters), Indiana University (five chapters), the University of California at Berkeley (two chapters), Lawrence Livermore Laboratories (two chapters), the University of California at Davis (one chapter), and the Univerisdad de Murica (one chapter). In addition, there are two chapters from persons who are not at one of the centers named but have an interest and expertise in an area of adaptive optics. So the book has the flavor of a series of individual papers on a generally common theme.The book is organized broadly into sections dealing with overall information on adaptive optics systems and the components that comprise them, use of adaptive optics in retinal imaging, use of adaptive optics in vision correction, and finally examples of adaptive optics systems built at the various centers. Most of these sections offer the type of information that a person inquiring into the use of adaptive optics in vision science would be interested in and the sort of thing one would expect to find in a book of this type.The section on Vision Correction Applications is an unexpected guest at the party. It is really not about adaptive optics at all. It is somewhatrelated to adaptive optics in that adaptive optics are used to remove the aberrations of the eye, but really the chapters in this section are about the aberrations of the eye and various nonadaptive methods to correct them. They include wavefront corrected contact lenses, wavefront guided laser refractive corrections, such as PRK and LASIK treatments, and a somewhat philosophic discussion of what the refractive state of the eye means when one considers complex refractive error, such as that revealed by wavefront measurement.There is also a very interesting, but somewhat unexpected chapter on the structure of the retina. Of course viewing the retinal structure in ever increasing detail is one of the primary reasons for employing adaptive optics. So it does make sense to know what one should be looking for and the resolution one will need to see it. Perhaps then it makes sense to find this chapter in a book that is supposed to be about adaptive optics and its use in vision research.I now turn to the question of whether or not the book will truly be a proper guide for someone with a need and desire to understand the technology and use of adaptive optics in vision science. Let us approach this by asking - what does one need to know?To correct the aberrations of the eye you first have to know what they are and you need a way to measure them. There is a chapter on the type of aberrations expected to be found in the eye, and explanations in several chapters on the theory and design of the principal type of wavefront sensor used today, the Shack-Hartmann wavefront sensor. Each chapter in which the Shack-Hartmann sensor is discussed, does so in a slightly different fashion and sometimes these explanations do not completely agree with one another. It appears as though there was not an overall technical editing effort or inter-book peer review done here.Next, you have to know what is available to alter a wavefront to achieve the desired diffraction limited state. Then having identified the device, one needs to understand how to control it using the available wavefront error information. To address these questions the book has chapters that describe the various types of deformable mirrors and other devices, such as variable phase elements, that are available and that have been used in adaptive optics systems used in vision research. Since different centers have used different devices and there are new devices being developed, one has to read through the book to get a good idea of what is available and what has been used to date. There is also the matter of the control of the adaptive optical device, whatever it is, and several chapters are devoted to overall control strategies, software for this task, and related considerations.Once you know how to sense wavefront error and how you might remove it, you have to decide what you want to examine and what type of overall system would be best for this task. Several chapters address this topicin a variety of ways. Some authors address the resolution that can be achieved, or has been achieved, with different system designs. Some authors give fairly detailed guidance on the components needed in an adaptive optics system and how to approach the design. One chapter addresses putting a system together and aligning it. While the book offers a wealth of information in this area, it is scattered throughout a number of chapters so it not easy to find exactly what you might need to know unless you read through the whole book.Finally, you might be interested in what has been used to date at the various participating centers. For this the book is quite helpful in that there is a separate section on Design Examples in which each chapter is authored by persons at a single center and tells, in quite comprehensive detail, about the system found at that particular center.At the end of the book there is an appendix that reproduces the first attempt to standardize the reporting of the aberrations of the human eye that was done 8 years ago by a task force associated with the Optical Society of America. Since that time, this early effort has been improved and expanded upon by the American National Standards Institute and there has existed since 2004, a comprehensive standard on this important matter. It is a shame that the authors of this book did not recognize the existence of this more modern and official standard, ANSI Z80.28 to 2004 –Methods for Reporting Optical Aberrations of Eyes.This then is a very brief summary what Adaptive Optics for Vision Science has to offer and I return to the question of whether it equips “engineers, scientists, and clinicians with the basic concepts, engineering tools, and tricks of the trade required to master adaptive optics-related application in vision science and ophthalmology.” May I first say that if a person wished to design and build an adaptive optics system and use it for vision research that person would be well advised to start as an apprentice at a center that has such a system in operation. That is because systems of this sort have complexity at all levels and of a very detailed, system specific nature, such that no book or series of books could properly prepare a person for the task of creating a successful system. So a book can only give a general overall view of what needs to be done – which is quite different from what you really need to know to do it. This is why the stated goal of this book is probably an impossible task.But still there is a difference – even for a task of this sort – between a great effort and something less. If too much detail is included it is very hard to for the reader to distinguish between what is really important and what is not. On the other hand, if the treatment is simply a broad overview then it is not much help when specific questions arise. It seems to me the best way to proceed is fully acquaint the reader with the important considerations and questions in the field and then,after giving fairly general guidance on them, to teach the reader how to think about them and to approach their solution. It is the old plan of ‘not giving a man a fish a day so he can eat but teaching him how to fish.’ If anything, Adaptive Optics for Vision Science is weak in this area. There is a wealth of information in the book but it is a little hard to get at due to the way the book is organized. Each author was obviously given a topic and told to proceed. This leads to duplication of effort and makes it hard to go to one place in the book to learn of a particular area of interest. Having participated, as an author, in a book of this type I know of the difficulty of getting the various authors to coordinate the separate chapters. It is the major task of the editor of the book to achieve this harmonization, and really it can only be well done if it is a recognized goal from the start of the work and all participants are aware of it.In summary Adaptive Optics for Vision Science is a very interesting record of the early days of an exciting new field in vision science, rich in detail and quite informative but a little hard to digest.Charles CampbellBerkeley, California在自适应光学视觉科学在过去十年一直是一个非常高效和有趣的时间为那些视力科学家谁研究了人眼的视网膜结构。