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[转自汪秉宏同学英译汉]诺贝尔奖得主高锟的获奖演说

已有 4464 次阅读 2009-12-18 12:40 |个人分类:信息交流|系统分类:人物纪事| 诺贝尔奖得主, 高锟的获奖演说, 高锟夫人黄美芸代讲

Sand from centuries past;

Send future voices fast.
亘古砂石递捷音

-诺贝尔奖得主高锟的获奖演说,高锟夫人黄美芸代讲

[按语]转发汪秉宏的大学同学陈锡浩(曾在上海阿尔卡特光缆有限公司工作的光纤光缆研发专家),对于诺贝尔奖得主高锟获奖演说英文稿的全文汉译。

 

A Nobel Lecture organized by the Royal Swedish Academy of Sciences and The Prize Committee in Physics delivered by Mrs Gwen MW Kao on behalf of Prof Charles K Kao Nobel Laureate in Physics 2009 8 December 2009 Aula Magna Stockholm University
2009128高锟夫人黄美芸代表2009年诺贝尔物理奖得主高锟教授在Aula Magna Stockholm大学由瑞典皇家科学院和物理学奖委员会组织的演讲会上的演讲。


1. Introduction
引言
It is sad that my husband, Professor Charles Kao, is unable to give this lecture to you himself. As the person closest to him, I stand before you to honour him and to speak for him. He is very very proud of his achievements for which the Nobel Foundation honours him. As are we all!

非常抱歉,我的丈夫高锟教授不能亲自为你们演讲。作为他最亲近的人,我站在你们面前对他表示敬意代他进行演讲。他为被授予诺贝尔奖的成就而感到非常非常的骄傲,就像我们所有人一样!

In the 43 years since his seminal paper of 1966 that gave birth to the ubiquitous glass fiber cables of today, the world of telephony has changed vastly. It is due to Professor Kao’s persistence in the face of skepticism that this revolution has occurred.

1966年他的论文的发表诞生了今天无处不有的玻璃光纤光缆的43年以来,世界通话技术的变化实在是太大了。正是因为高锟教授面对怀疑的坚持,才发生了这样的革命。

In the 1970s the pre-production stage moved to ITT Corp Roanoke VA, USA. Whilst Charles worked there, he received two letters. One contained a threatening message accusing him of releasing an evil genie from its bottle; the other, from a farmer in China, asked for a means to allow him to pass a message to his distant wife to bring his lunch. Both letter writers saw a future that has since become past history.

1970年代,前期制作阶段移到了美国维吉尼亚州罗诺克的ITT公司。当时在那儿工作高锟的收到了两封信。一封信含有威胁的信息指责他从瓶中释放了邪恶魔鬼;另一封来自一位中国农民,请教怎样才能告诉他远方的妻子送来午餐。两位作者都看到了一种未来,而这已经成为了历史。
In the 1960s, our children were small. Charles often came home later than normal – dinner was waiting as were the children. I got very annoyed when this happened day after day. His words, maybe not exactly remembered, were –‘Please don’t be so mad. It is very exciting what we are doing; it will shake the world one day!’ I was sarcastic, ‘Really, so you will get the Nobel Prize, won’t you!’
He was right – it has revolutionized telecommunications.
1960年代,我们的孩子还小。高锟经常回家比往常晚——晚餐在等他,孩子们也在等他。每天如此使我很恼怒。他说道,也许我记得不那么确切——“不要那么发火。我们正在做一件非常激动人心的工作,有一天它将震撼世界!我讥讽道,真的,那么你将会获得诺贝尔奖,不是吗?

他是对的——它使电信技术发生了一场革命。


2. The early days
早年
In 1960, Charles joined Standard Telecommunications Laboratories Ltd. (STL), a subsidiary of ITT Corp in the UK, after having worked as a graduate engineer at Standard Telephones and Cables in Woolwich for some time. Much of the work at STL was devoted to improving the capabilities of the existing communication infrastructure with a focus on the use of millimeter wave transmission systems.

1960年,在Woolwich标准电话和电缆公司作为应届毕业生工程师工作一段时间之后,高锟加入了标准电信实验室公司(STL),那是英国ITT公司的一个下属公司。STL的很多工作旨在提高既有通信设施的性能,致力研究采用毫米波传输系统。

Millimeter waves at 35 to 70 GHz could have a much higher transmission capacity. But the waters were uncharted and the challenges enormous, since radio waves at such frequencies could not be beamed over long distances due to beam divergence and atmospheric absorption. The waves had to be guided by a waveguide. And in the 1950’s, R&D work on low loss circular waveguidesHE11mode– was started. A trial system was deployed in the 1960s. Huge sums were invested, and more were planned, to move this system into the pre-production stage. Public expectation for new telecommunication services such as the video phone had heightened.
35
70 GHz的毫米波可有相当高的传输能力。但是这是一个未知的领域,挑战巨大。这一频率的电波因波束发散及大气吸收不能长距离传送。得用波导引导电波。1950年代,开始了对低损耗HE11模圆波导的研发。1960年代建立了试验系统。为了使这一系统推入前期制作阶段投入了无数的资金,更多款项在计划中。公众期望着新的如可视电话那样的电信服务得到提高。

Charles joined the long-haul waveguide group led by Dr Karbowiak at STL. He was excited to see an actual circular waveguide. He was assigned to look for new transmission methods for microwave and optical transmission. He used both ray optics and wave theory to gain a better understanding of waveguide problems – then a novel idea. Later, his boss encouraged him to pursue a doctorate while working at STL. So Charles registered at University College London and completed the dissertation ‘Quasi-Optical Waveguides’ in two years.

STL,高锟参加了Karbowiak博士领导的长距离波导组。他为看到实际圆波导感到非常惊喜。他被分派寻找微波和光的新的传输方法。他同时采用了射线光学和波动理论以便更好地理解波导问题——那在当时是新观念。后来,他老板鼓励他在STL边工作边攻读博士学位。于是他注册在伦敦大学学院,并在两年里完成了他题为“准光波导”的博士论文。

The invention of the laser in 1959 gave the telecom community a great dose of optimism that optical communication could be just around the corner. The coherent light was to be the new information carrier with capacity a hundred thousand times higher than point-to-point microwaves –based on the simple comparison of frequencies: 300 terahertz for light versus 3 gigahertz for microwaves.

1959年激光的发明使得电信界极为乐观,认为光通信讲指日可待。相干光被认为是容量比之点到点的微波要高十万倍的新的信息载体——根据对频率的简单比较:光的300 terahertz1 terahertz=1012赫兹)对微波的3 gigahertz1 gigahertz=109赫兹)。

The race between circular microwave waveguides and optical communication was on, with the odds heavily in favour of the former. In 1960, optical lasers were in their infancy, demonstrated at only a few research laboratories, and performing much below the needed specs. Optical systems seemed a non-starter.

微波圆波导同光通信之间的竞赛开始了,而前者胜算的机会要大得多。1960年激光器尚在襁褓之中,仅在少数几个实验室有演示,并且性能远非众望。光系统看来希望不大。
But Charles still thought the laser had potential. He said to himself: ‘How can we dismiss the laser so readily? Optical communication is too good to be left on the theoretical shelf.’
但是高锟仍旧认为激光是有潜力的。他对自己说:“我们怎么能这样轻易地将激光除名?光通信不能好得只停留在理论层面上”。

He asked himself the obvious questions:
1. Is the ruby laser a suitable source for optical communication?
2. What material has sufficiently high transparency at such wavelengths?
At that time only two groups in the world were starting to look at the transmission aspect of optical communication, while several other groups were working on solid state and semiconductor lasers. Lasers emit coherent radiation at optical frequencies, but using such radiation for communication appeared to be very difficult, if not impossible. For optical communication to fulfill its promises, many serious problems remained to be solved.

他问自己几个显而易见的问题:

1. 红宝石激光器是不是一种适合光通信的光源?

2. 什么材料在那样的波长下有足够高的透明度?

当时,世界上只有两个小组开始关注光通信的传输方面,其它几个小组在固体和半导体激光器方面进行研究。激光器在光频下辐射相干光,但是要在通信上利用这样的辐射看来即便不是不可能也是极为困难的。对于光通信来说在满足这一要求之前,必须解决存在的许多严重问题。


3. The key discovery
关键发现
In 1963 Charles was already involved in free space propagation experiments: the rapid progress of semiconductor and laser technology had opened up a broader scope to explore optical communication realistically. With a helium-neon laser beam directed to a spot some distance away, the STL team quickly discovered that distant laser light flickered. The beam danced around several beam diameters because of atmospheric fluctuations.
The team also tried to repeat experiments done by other research laboratories around the world. For example, they set up con-focal lens experiments similar to those at Bell Labs: a series of convex lenses were lined up at intervals equal to the focal length. But even at the dead of night when the air was still and even with refocusing every 100 meters, the beam refused to stay within the lens aperture.

Bell Labs experiments using gas lenses were abandoned due to the difficulty of providing satisfactory insulation while maintaining the profiles of the gas lenses. These experiments were struggles in desperation, to control light travelling over long distances.

早在1963年,高锟便已从事自由空间传输实验:半导体技术和激光技术的飞速进展将探索范围现实地展宽到了光通信。将氦氖激光束导向远处的光斑,STL的团队很快发现远处激光在闪烁。由于大气涨落,光束在几个光束直径位置附近跳动。小组还尝试重复世界上其它实验室进行的实验。例如,他们建立了类似于贝尔实验室的共焦透镜(con-focal lens)实验:将一系列凸透镜以等于焦距的间隔排成直线。但是,即使在空气静止的深夜即使每100进行再聚焦,光束还是不能停留在透镜孔径之内。

因为不能在维持气体透镜轮廓的同时提供满意的隔热性,贝尔实验室采用的气体透镜被放弃了。这些实验是为使光在长距离传输而进行的拼命的奋斗。

At STL the thinking shifted towards dielectric waveguides. Dielectric means a non-conductor of electricity; a dielectric waveguide is a waveguide consisting of a dielectric cylinder surrounded by air. Dr Karbowiak suggested Charles and three others to work on his idea of a thin film waveguide.

But thin film waveguides failed: the confinement was not strong enough and light would escape as it negotiates a bend.
STL,思路移向了介质波导。介质意味着电的非导体;介质波导是由一周围是空气的介质圆柱体构成的。Karbowiak博士建议高锟和其他三位同事按照他的思路在薄膜波导上研究。

但是薄膜波导不成功:约束不够强烈,一遇到弯曲光就逃逸。

When Dr Karbowiak decided to emigrate to Australia, Charles took over as the project leader and he then recommended that the team should investigate the loss mechanism of dielectric materials for optical fibers.

这时Karbowiak博士决定移居澳大利亚,高锟接替他成为项目负责人,并建议团队应对制作光纤用介质材料的损耗机理进行研究。

A small group worked on methods for measuring material loss of low-loss transparent materials. George Hockham joined him to work on the characteristics of dielectric waveguides. With his interest in waveguide theory, he focused on the tolerance requirements for an optical fiber waveguide; in particular, the dimensional tolerance and joint losses. They proceeded to systematically study the physical and waveguide requirements on glass fibers.

一个小小组进行了低损耗透明物质材料损耗测试方法的研究。George Hockham同他一起研究介质波导的特性。带着对波导理论的兴趣,他关注了光纤波导的容差要求;特别是,尺寸容差和连接损耗。他们进行了玻璃光纤的物理和波导要求的系统性研究。

In addition, Charles was also pushing his colleagues in the laser group to work towards a semiconductor laser in the near infrared, with emission characteristics matching the diameter of a single-mode fiber. Single mode fiber is optical fiber that is designed for the transmission of a single ray or mode of light as a carrier. The laser had to be made durable, and to work at room temperatures without liquid nitrogen cooling. So there were many obstacles. But in the early 1960s, esoteric research was tolerated so long as it was not too costly.

另外,高锟让他在激光器小组的同事朝辐射特性同单模光纤直径相匹配的近红外半导体激光器方向进行研究。单模光纤是一种设计来传输单一射线或单一光模式的光纤载体。激光器得做成耐久、无需液氮冷却可室温运行。因此,困难很多。但是在1960年代早期,只要花费不是很大,进行深奥的研究是允许的。
Over the next two years, the team worked towards the goals. They were all novices in the physics and chemistry of materials and in tackling new electromagnetic wave problems. But they made very credible progress in considered steps. They searched the literature, talked to experts, and collected material samples from various glass and polymer companies. They also worked on the theories, and developed measurement techniques to carry out a host of experiments. They developed an instrument to measure the spectral loss of very low-loss material, as well as one for scaled simulation experiments to measure fiber loss due to mechanical imperfections.

随后的两年间,团队朝着这些目标进行了研究。他们在材料的物理学和化学方面都是新手,同时却要处理新的电磁波问题。但是他们以一步步地取得了可靠的进展。他们检索文献、同专家交谈、到各个玻璃公司和聚合物公司收集材料样品。他们还进行理论研究,开发了测试技术进行了许多实验。他们开发了一台仪器测试极低损耗材料的光谱损耗,并进行比例模拟实验测试光纤因机械缺陷导致的损耗。

Charles zeroed in on glass as a possible transparent material. Glass is made from silica –sand from centuries past that is plentiful and cheap.

The optical loss of transparent material is due to three mechanisms: (a) intrinsic absorption, (b)extrinsic absorption, and (c) Rayleigh scattering. The intrinsic loss is caused by the infrared absorption of the material structure itself, which determines the wavelength of the transparency regions. The extrinsic loss is due to impurity ions left in the material and the Rayleigh loss is due to the scattering of photons by the structural non-uniformity of the material. For most practical applications such as windows, the transparency of glass was entirely adequate, and no one had studied absorption down to such levels. After talking with many people, Charles eventually formed the following conclusions.

1. Impurities, particularly transition elements such as iron, copper, and manganese, have to be reduced to parts per million or even parts per billion. However, can impurity concentrations be reduced to such low levels?
2. High temperature glasses are frozen rapidly and therefore are more homogeneous, leading to a lower scattering loss.
The ongoing microwave simulation experiments were also completed. The characteristics of the dielectric waveguide were fully defined in terms of its modes, its dimensional tolerance both for end-to-end mismatch and for its diameter fluctuation along the fiber lengths. Both the theory and the simulated experiments supported the approach.
They wrote the paper entitled, ‘Dielectric-Fibre Surface Waveguides for Optical Frequencies’ and submitted it to the Proceedings of Institute of Electrical Engineers. After the usual review and revision, it appeared in July 1966 – the date now regarded as the birthday of optical fiber communication.
作为一种可能的透明物质,高锟锁定了玻璃。 玻璃是由硅石——几千年来的砂子做成的,到处都是而且价廉。

透明物质的光损耗出于三个机理:(a) 本征吸收,(b) 非固有吸收,(c) 瑞利散射。本征吸收是材料结构本身导致的红外吸收,它决定了透明区域的波长范围。非固有吸收是由材料中存在的杂质离子引起的,瑞利损耗则是由光子因材料结构不均匀导致的散射所致。对于如窗玻璃那样的多数实际应用,玻璃的透明度完全足够,没有人被要求去研究如何降低那样程度的吸收。在同许多人交谈后,高锟终于得出了以下结论:
1. 杂质、特别是如铁、铜、锰那样的过渡元素含量应该降低到数百万分甚至数十亿分之一。但是,杂质浓度是否能够降低到这种地步?

2. 高温玻璃是迅即冷却制成的,因而更均匀有较低的散射损耗。

开展的微波模拟实验也完成了。介质波导的特性完全由其模式、它在端对端失配时的尺寸容差及沿着光纤长度方向的直径波动所规定。理论和实验两者都支持研究。

他们撰写了题为“光频介质光纤表面波导”的论文,递交到Proceedings of Institute of Electrical Engineers。经过普通的审查和修改后论文于19667月发表——这一日期现在被视为光纤通信的诞生日期。


4. The paper论文
The paper started with a brief discussion of the mode properties in a fiber of circular cross section.

The paper then quickly zeroed in on the material aspects, which were recognized to be the major stumbling block. At the time, the most transparent glass had a loss of 200 dB/km, which would limit transmission to about a few meters – this is very obvious to anyone who has ever peered through a thick piece of glass. Nothing can be seen.

But the paper pointed out that the intrinsic loss due to scattering could be as low as 1 dB/km, which would have allowed propagation over practical distances. The culprit is the impurities: mainly ferrous and ferric ions at these wavelengths. Quoting from the paper: ‘It is foreseeable that glasses with a bulk loss of about 20 dB/km at around 0.6 micron will be obtained, as the iron-impurity concentration may be reduced to 1 part per million’. In layman terms, if one has a sufficiently ‘clean’ type of glass, one should be able to see through a slab as thick as several hundred meters. That key insight opened up the field of optical communications.
论文以开头简要地讨论了圆截面光纤的模式特性。

然后论文迅即转向材料方面,那被认为是主要的绊脚石。那时,最透明的玻璃损耗有200 dB/km,从而使传输限于大约几米的长度上——对于任何在厚玻璃块边张望过的人,那是显而易见的。什么也看不见。

但是文章指出:起因散射而产生的本征损耗可以低达1dB/km, 从而可在实用距离下传输。罪魁祸首是杂质:主要是这些波长的二阶和三阶铁离子。论文说:“可以预见,由于铁离子浓度也许能降到百万分之一,将能够获得0.6微米波长下损耗为20 dB/km的块状玻璃” 。用通俗的话说来,如果你能使一种玻璃足够地“清洁”, 你就能透过厚达几百米的薄玻璃块看东西。这一关键洞察开辟了光通信的领域。

The paper considered many other issues:
? The loss can be reduced if the mode is chosen so that most of the energy is actually outside the fiber.
? The fiber should be surrounded by a cladding of lower index (which became the standard technology).
? The loss of energy due to bends in the fiber is negligible for bends larger than 1 mm.
? The losses due to non-uniform cross sections were estimated.
? The properties of a single-mode fiber (now a key technology especially for long distance and high data rate transmission) were analyzed. It was explained how dispersion limits bandwidth; an example was worked out for a 10 km route – a very bold scenario in 1966.
论文还考虑了一些其它议题:

?如果进行模式选择,使得大部分能量实际上在光纤外,损耗就可以降低。

?光纤应为周围折射率较低的包层所包围(这已成为标准工艺)。

?光纤弯曲导致的能量损耗对于大于1mm的弯曲来说可以忽略。

?估算了截面不均匀引起的损耗。

?分析了单模光纤的性质(它现在是关键技术,对于长距离高速率传输来说尤其如此)。说明了色散会怎样限制带宽; 给出了10km路由的结果——在1966年,这是一个非常大胆的方案。

It may be appropriate to quote from the Conclusion of this paper:
The realization of a successful fiber waveguide depends, at present, on the availability of suitable low-loss dielectric material. The crucial material problem appears to be one which is difficult but not impossible to solve. Certainly, the required loss figure of around 20 dB/km is much higher than the lower limit of loss figure imposed by fundamental mechanisms.
引用论文的结论部分可能是恰当的:

光纤波导的成功实现,现在取决于能否获得适当的低损耗介质材料。关键材料看来是一个很困难但不是不可解决的问题。当然,要求20dB/km左右的低损耗值已经远远高于根据基本机理得到的损耗极限值。
Basically all of the predictions pointed accurately to the paths of developments, and we now have 1/100 of the loss and 10,000 times the bandwidth then forecast – the evolutionary proposal in the 1966 paper was in hindsight too conservative.

所有预言指出的开发方向基本上正确,现在我们已经有了损耗等于预言的1/100、带宽等于预言10000倍的光纤——事后看来,1966年的进化建议还是太保守了。


5. Convincing the world
说服世界
The substance of the paper was presented by Dr Kao at an IEE meeting in February 1966. Most of the world did not take notice – except for the British Post Office (BPO) and the UK Ministry of Defense, who immediately launched major research programs. By the end of 1966, three groups in the UK were studying the various issues involved: Kao himself at STL; Roberts at BPO; Gambling at Southampton in collaboration with Williams at the Ministry of Defense Laboratory.

19662月高锟在IEE会议上发表了论文的实质部分。世界的多数没有加以理会——BPO(英国邮电)和英国国防部除外,它们立即启动了研究程序。1966年底,三个研究各种课题的英国研究小组包括:高锟本人所在的STLBPORoberts;同国防部实验室Williams合作的SouthamptonGambling小组。
In the next few years, Dr Kao traveled the globe to push his idea: to Japan, where enduring friendships were made dating from those early days; to research labs in Germany, in the Netherlands and elsewhere to spread his news. He said that until more and more jumped on the bandwagon, the use of glass fibers would not take off. He had tremendous conviction in the face of widespread skepticism. The global telephony industry is huge, too large to be changed by a single person or even a single country, but he was persistent and his enthusiasm was contagious, and slowly he converted others to be believers.

在随后的若干年间,高锟走遍世界宣传他的观点:在日本,他重温了过去持久的友谊;在德国的研究室,在荷兰和其他一些地方宣传他的论文。他说,除非越来越多的人表示支持,玻璃光纤的应用不会起飞。面对着普遍的怀疑主义他信心十足。全球的电话产业十分巨大, 大到难以被一个个人甚至一个国家所改变。但他坚持着,他热情而富有感染力,逐渐说服了别人。
The experts at first proclaimed that the materials were the most severe of the intrinsic insurmountable problems. Gambling wrote that British Telecom had been ‘somewhat scathing’ about the proposal earlier, and Bell Labs, who could easily have led the field, simply failed to take notice until the proven technology was pointed out to them. Dr Kao visited many glass manufacturers to persuade them to produce the clear glass required. He got a response from Corning, where Maurer led the first group that later produced the glass rods and developed the techniques to make the glass fibers to the required specifications.

专家们起先声称材料是本质上难以解决的问题中的最严重的问题。Gambling写道:英国电信已经对先前的建议表示某种程度的不满,而很容易引领该领域的贝尔实验室则简单地不予理会直到验证技术出席为止。高锟访问了多个玻璃制造厂劝说他们生产要求的透明玻璃。他在康宁得到了响应,Maurer领导了后来生产玻璃棒并按所要求规格制造光纤进行技术开发的第1个小组。

Meanwhile, Dr Kao continued to pour energy into proving the feasibility of glass fibers as the medium for long-haul optical transmission. They faced a number of formidable challenges. The first was the measurement techniques for low-loss samples that were obtainable only in lengths of around 20 cm. The problem of assuring surface perfection was also formidable. Another problem is end surface reflection loss, caused by the polishing process. They faced a measurement impasse that demanded the detection of a loss difference between two samples of less than 0.1%, when the total loss of the entire 20 cm sample is only 0.1%. An inexact measurement would be meaningless.

同时,高锟继续为证明玻璃光纤作为长距离光传输的媒质的可行性倾注精力。他们面临着巨大的挑战。首先是关于获得的长度仅约20cm的低损耗样品的测试技术。确保表面完善十分困难。另一问题是抛光过程引起的末端表面的反射损耗。他们面对的测试难题是要求测出两个样品间小于0.1%的损耗差,而20cm样品的总损耗却只有0.1%。不精确的测试毫无意义。
In 1968 and 1969, Dr Kao and his colleagues Davies, Jones and Wright at STL published a series of papers on the attenuation measurements of glass that addressed the above problems. At that time, the measuring instruments called spectrophotometers had a rather limited sensitivity – in the range of 43 dB/km. The measurement was very difficult: even a minute contamination could have caused a loss comparable to the attenuation itself, while surface effects could easily be ten times worse. Dr Kao and the team assembled a homemade single-beam spectrophotometer that achieved a sensitivity of 21.7 dB/km. Later improvements with a double-beam spectrophotometer yielded a sensitivity down to 4.3 dB/km.

19681969年,高锟和他在STL的同事Davies, JonesWright就玻璃的衰减测试发表了一系列论述上述问题的论文。那时,一种称为分光光度计的测试仪器灵敏度相当有限——在43 dB/km左右。测试非常困难:一点点污染就会引起可同衰减值本身相比拟的损耗, 而表面效应则很容易十倍地糟糕。高锟和他的团队自行组装了一台单光束分光光度计,灵敏度达到21.7 dB/km。后来改进的双光束分光光度计,灵敏度则达到4.3dB/km

The reflection effect was measured with a homemade ellipsometer. To make it, they used fused quartz samples made by plasma deposition, in which the high temperature evaporated the impurity ions. With the sensitive instrument, the attenuation of a number of glass samples was measured and, eureka, the Infrasil sample from Schott Glass showed an attenuation as low as 5 dB/km at a window around 0.85 micron – at last proving that the removal of impurity would lower the absorption loss to useful levels.

用自制椭圆度计测试了反射效应。为了自制它,他们采用了等离子沉积得到的熔融石英样品,其杂质离子已在高温下蒸发。利用灵敏的仪器,测试了许多玻璃样品的衰减。终于有了,Schott玻璃公司的红外硅样品在0.85微米波长呈现了低达5 dB/km的衰减——终于证明去除杂质可将吸收损耗降到可用的大小。
This was really exciting because the low-loss region is right at the gallium-arsenide laser emission band. The measurements clearly pointed the way to optical communication –compact gallium-arsenide semiconductor lasers as the source, low-cost cladded glass fibers as the transmission medium, and silicon or germanium semiconductors for detection. The dream no longer seemed remote. These measurements apparently turned the sentiments of the research community around. The race to develop the first low-loss glass fiber waveguide was on.

这实在令人振奋,因为低损耗窗口正处于砷化镓激光器的发光波段。测试结果清楚地指出了光通信的道路——就是以紧凑的砷化镓半导体激光器为光源,廉价的包层光纤为传输媒质,硅或锗半导体为探测器。梦想的实现看来不再遥远。这些测试结果当然在研究界激起了激情。开发第一根低损耗玻璃光纤波导的竞赛开始了。
In 1967, at Corning, Maurer’s chemist colleague Schultz helped to purify the glass.

In 1968, his colleagues Keck and Zimar helped to draw the fibers. By 1970, Corning had produced a fiber waveguide with a loss of 17 dB/km at 0.633 micron using a titanium-diffused core with silica cladding, using the Outside Vapor Deposition (OVD) method. Two years later, they reduced the loss to 4 dB/km for a multimode fiber by replacing the titanium-doped core with a germanium-doped core.

Bell Labs finally got on the bandwagon in 1969 and created a programme in optical fiber research after having been skeptical for years. Their work on hollow light pipes was finally stopped in 1972. Their millimeter wave research programme was wound down and eventually abandoned in 1975.

1967年,在康宁,Maurer的化学家同事Schultz帮助进行了玻璃提纯
1968年,他的同事KeckZimar帮助进行了光纤拉丝。到了1970年,康宁用外气相沉积法(OVD)生产了在0.633微米波长下损耗为17 dB/km的光纤波导,其纤芯掺钛包层为石英。两年后,通过将掺钛纤芯换成掺锗纤芯他们制成了损耗降到4 dB/km的多模光纤。

贝尔实验室终于在1969年也赶上来了,经过了多年的怀疑之后他们制定了光纤研究计划。贝尔在中空光管方面的工作最终于1972年终止。毫米波的研究计划被放松,最终于1975年被放弃。
It was during this time of constant flying out to other places that this cartoon joke hit home: ‘Children, the man you see at the breakfast table today is your father!’

在这一不断地从一地飞往另一地的时期,我们家,正像一个卡通笑话所说的那样:“孩子们,今天你们在早餐餐桌上见到的那个人是你们父亲!”
We saw him for a few days and off he went again. Sometimes he flew off for the day for meetings at ITT Corp headquarters in New York. I would forget he had not left to go to the office and would phone his secretary to remind Charles to pick up milk or something on his way home.
His secretary was very amused: ‘Mrs Kao, don’t you know your husband is in New York today!’
我们看见他几天就马上送他离开。有时他白天飞往ITT在纽约的总部开会。我忘记他不曾去办公室上班会打电话给他秘书希望提醒高锟在回家的途中带一些牛奶或其它东西回来。
他秘书非常开心:“太太,难道你不知道你丈夫今天是在纽约!”


6. Impact on the world 对世界的影响
Since the deployment of the first-generation, 45-megabit-per-second fiber-optic communication system in 1976, the transmission capacity in a single fiber has rapidly increased a million fold to tens of terabits per second. Data can be carried over millions of km of fibers without going through repeaters, thanks to the invention of the optical fiber amplifier and wavelength division multiplexing. So that is how the industry grew and grew. The world has been totally transformed because of optical fiber communication. The telephone system has been overhauled and international long distance calls have become easily affordable.

Brand new mega-industries in fiber optics including cable manufacturing and equipment, optical devices, network system and equipment have been created.

Hundreds of millions of kilometers of glass fiber cables have been laid, in the ground and in the ocean, creating an intricate web of connectivity that is the foundation of the world-wide web.

The Internet is now more pervasive than the telephone used to be. We browse, we skype, we blog, we go onto you-tube, we shop, we socialize on-line. The information revolution that started in the 1990s could not have happened without optical fibers.
Over the last few years fibers are being laid all the way to our homes.
All-optical networks that are environmentally green are contemplated.
The revolution in optical fiber communication has not ended – it might still just be at the beginning.

自从第一代45Mb/s光纤通信系统在1976年部署以来,单模光纤的传输容量迅速地增加了一百万倍到达了数十Tb/s。由于光纤放大器和波分复用的发明,数据现在可以在几百万公里的光纤中传送而无需经过中继器。产业的发展有多快!因为光纤通信,世界已被完全改变。电话系统在更新,国际间的长途电话变得负担得起了。

包括缆的制造和设备、光器件、网络系统和设备在内的全新而庞大的光纤产业形成了。在地下、在海洋,数亿公里的玻璃光纤光缆已经敷设,错综复杂的网络节点已经形成,这是遍及世界的网络的基础。

现在,因特网比过去的电话网还要普及。我们浏览、我们打网络电话、我们博客,我们上you-tube、我们购物、我们进行网上交际。没有光纤,便不会发生始于1990年代的信息革命。
过去几年里,到处敷设光纤,通向我们的家庭。

环保的全光网络正在受到关注。

光纤通信的革命没有完结——它也许还刚刚起步。


7. Conclusion
结论

The world-wide communication network based on optical fibers has truly shrunk the world and brought human beings closer together. I hardly need to cite technical figures to drive this point home. The news of  the Nobel Prize reached us in the middle of the night at 3 am in California, through a telephone call from Stockholm (then in their morning) no doubt carried on optical fibers; congratulations came literally minutes later from friends in Asia (for whom it was evening), again through messages carried on optical fibers. Too much information is not always a good thing: we had to take the phone off the hook that night in order to get some sleep!
以光纤为基础的全球通信网的确缩小了世界,使人类越来越近。我几乎不需要引用技术数据而可以清晰地证明这一点。我们是在加利福尼亚半夜3点通过来自Stockholm的电话(那里是在早上)知道诺贝尔奖的消息的,毫无疑问是通过光纤;从亚洲的朋友那儿来的祝贺就在几分钟后到达(对他来说,那是傍晚),又是通过光纤传送的信息。太多的信息不总是好事:这一夜我们得摘下电话以便得到一些睡眠!

Optical communication is by now not just a technical advance, but has also caused major changes in society. The next generation will learn and grow up differently; people will relate to one another in different ways. Manufacturing of all the bits and pieces of a single product can now take place over a dozen locations around the world, providing huge opportunities for people especially in developing countries. The wide accessibility of information has obviously led to more equality and wider participation in public affairs.

现在光纤通信不但是一种技术进步,也在使社会发生巨大变化。我们的下一代将以完全不同的方式学习和成长;人们采用不同的途径相互联系。全部零零碎碎单个产品的制造现在可以在世界几十个不同地方进行,从而为人们特别是发展中国家的人民提供了巨大的机会。信息的广泛可接近性明显地导致了进一步的平等和人们对公众事务的更广泛的参与。
Many words, indeed many books have been written about the information society, and I do not wish to add to them here – except to say that it is beyond the dreams of the first serious concept of optical communication in 1966, when even 1 GHz was only a hope.
In conclusion, Charles and I want to thank the Professors at The Chinese University of Hong Kong, namely: Professor Young, Professor Wong, Professor Cheung and Professor Chen for their support in compiling this lecture for us. Charles would like to thank ITT Corp where he developed his career for 30 years and all those who climbed on to the bandwagon with him in the early days, as without the legions of believers the industry would not have evolved as it did. Charles Kao planted the seed; Bob Maurer watered it and John MacChesney grew its roots.

关于信息社会,已经有了许多文字、确切的说写了许多书,我不想在这里添加什么——除了说1966年首先提出庄重的光通信概念的梦想已被超过,那时连1GHz也只是一种愿望。

作为结论,高锟和我要感谢香港中文大学的教授们,他们是教授、教授、教授和陈教授, 感谢他们的支持,为我们编写了这一演讲稿。高锟也要感谢ITT公司,他在那里渡过了30年的职业生涯,他也要感谢所有那些早期追随他的人们,没有千军万马的信徒,产业就不会有现在那样的进步。高锟播下了种子;Bob Maurer进行了灌溉,而John MacChesney使它根深叶茂。



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