thomasedison外文介绍
篇一：Thomas Edison
Thomas Edison
Thomas Edison was born February 11, 1847 in Milan, Ohio. He was nicknamed "Al" at an early age. At age 11, Edison moved to Michigan where he spent the remainder of his childhood.
Thomas Edison struggled at school, but learned to love reading and conducting
experiments from his mother who taught him at home. At age 15, Edison became a "tramp telegrapher", sending and receiving messages via morse code, an
electronically-conveyed alphabet using different clicks for each letter. Eventually, he worked for the Union Army as a telegrapher. Edison often entertained himself by taking things apart to see how they worked. Soon, he decided to become an inventor.
In 1870, Edison moved to New York City and improved the stock ticker. He soon formed his own company that manufactured the new stock tickers. He also began working on the telegraph, and invented a version that could send four messages at once.
Meanwhile, Edison married Mary Stillwell, had three children and moved his family to Menlo Park, New Jersey where he started his famous laboratory.
In 1877, Edison, with help from "muckers", individuals from around the world looking to make fortunes in America, invented the phonograph. The phonograph was a machine that recorded and played back sounds. He perfected the phonograph by recording "Mary had a Little Lamb" on a piece of tin foil! In 1878, Edison invented the light bulb as well as the power grid system, which could generate electricity and deliver it to homes through a network of wires. He subsequently started the Edison Electric Light Company in October of 1878.
In 1884, after he attained great fame and fortune, Mary Stillwell died. Edison remarried 20 year old Mina Miller in 1886. He had three more children and moved to West Orange, New Jersey. At West Orange, Edison built one of the largest laboratories in the world. He worked extremely hard and registered 1,093 patents. Edison continued to invent or improve products and make significant contributions to x-ray technology, storage batteries and motion pictures (movies). He also invented the world's first talking doll. His inventions changed the world forever. They still influence the way we live today. Edison worked until his death on October 18, 1931.
1. In what state did Thomas Edison NOT live?
A. ? Michigan
B. ? Ohio
C. ? New York
II. Vocabulary notes:
1. remainder n. the rest
2. struggle v. try hard
3. convey v. carry
4. manufacture v. make sth in the factory
5. version n. a particular form of sth
6.subsequently adv. later
7. generate v. produce
8. patent n. right given by government to an inventor
9. fortune n. treasure
After reading
I. Complete each sentence with the given words in the box. There is one more
word than you need.
A. remainder B. struggle C. convey D. manufacture E. version F. subsequently G. generate H. patent I. fortune
1. Those who have lost their jobs _____________ to pay their supermarket bills.
2. Our company ____________ various types of machine tools.
3. The prisoner is _______________ freed.
4. He is creative, and he owned several _______________.
5.The company, New England Electric, burns coal to ____________ power.
6.She won a ___________ in a lottery.
7. The _____________ of the money must be paid by the end of June.
8. I found it hard to ____________ my feelings in word.
9. The new __________ of this dictionary is not in use yet.
1.B.
2.D.
3.F.
4.H
5.G
6.I
7.A.
8.C.
9.E.
篇二：Thomas Edison
Thomas Edison
爱迪生
I think 1847 is unusual, because Thomas Edison was born this year. Do you know him? He is one of the most famous persons all around the world. And his birthday is November 2nd. He started to go to school at the age of 8.
He sold newspapers on a train in 1859. And he began working early, he left home to work in different cities when he was only 18 years old. In 1869, he moved to New York to become an inventor.
I think he is very creative, because he could have 1903 inventions from 1868 to 1931. He is a talented inventor, isn't he?
篇三：英语学习_Thomas Edison_必备
弃我去者，昨日之日不可留
乱我心者，今日之日多烦忧
Thomas Edison
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"Edison" redirects here. For other uses, see Edison (disambiguation).
Thomas Alva Edison
"Genius is one per cent inspiration, ninety-nine per cent perspiration." - Thomas Edison,
Harper's Monthly (September 1932)
Born: February 11, 1847
Milan, Ohio, United States
Died: October 18, 1931
West Orange, New Jersey, United States
Occupation: Inventor, entrepreneur
Spouse: Mary Edison, Mina Edison
Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who developed many devices which greatly influenced life in the 20th century. Dubbed "The Wizard of Menlo Park" by a newspaper reporter, he was one of the first inventors to apply the principles of mass production to the process of invention, and can therefore be credited with the creation of the first industrial research laboratory. Some of the inventions credited to him were not completely original, but improvements of earlier inventions, or were actually created by numerous employees working under his direction. Nevertheless, Edison is considered one of the most prolific inventors in history, holding 1,097 U.S. patents in his name, as well as many patents in the United Kingdom, France,
and Germany.
Early life
Thomas Edison was born in Milan, Ohio, the seventh child of Samuel Ogden Edison, Jr.(1804-1896) and the former Nancy Matthews Elliott (1810–1871). His family was of Dutch origin. [1] He had a late start in his schooling as the result of an illness. His mind often wandered and his teacher the Reverend Engle was overheard calling him "addled". This ended Edison's three months of formal schooling. His mother had been a school teacher in Canada and happily took over the job of schooling her son. She encouraged and taught him to read and experiment. He recalled later, "My mother was the making of me. She was so true, so sure of me; and I felt I had something to live for, someone I must not disappoint."[2] Many of his lessons came from reading R.G. Parker's School of natural philosophy. Edison became hard of hearing at the age of twelve. There are many theories of what caused this; according to Edison he went deaf
because he was pulled up to a train car by his ears.[3]
Thomas's life in Port Huron, Michigan was bittersweet. He sold candy and newspapers on trains running from Port Huron to Detroit. Partially deaf since adolescence, he became a telegraph operator after he saved Jimmie Mackenzie from being struck by a runaway train. Jimmie's father, station agent J.U. Mackenzie of Mount Clemens, Michigan, was so grateful that he took Edison under his wing and trained him as a telegraph operator. Edison's deafness aided him as it blocked out noises and prevented Edison from hearing the telegrapher sitting next to him. One of his mentors during those early years was a fellow telegrapher and inventor named Franklin Leonard Pope, who allowed the then impoverished youth to live and work in the basement of his Elizabeth, New Jersey home.
Some of his earliest inventions related to electrical telegraphy, including a stock ticker. Edison applied for his first patent, the electric vote recorder, on October 28, 1868.
Beginning his career
Edison and his early phonograph, 1877Thomas Edison began his career as an inventor in Newark, New Jersey, with the automatic repeater and other
improved telegraphic devices, but the invention which first gained him fame was the phonograph in 1877. This accomplishment was so unexpected by the public at large as to appear almost magical. Edison became known as "The Wizard of Menlo Park," New Jersey, where he lived. His first phonograph
recorded on tinfoil cylinders that had low sound quality and destroyed the track during replay so that one could listen only a few times. In the 1880s, a redesigned model using wax-coated cardboard cylinders was produced by Alexander Graham Bell, Chichester Bell, and Charles Tainter. This was one reason that Thomas Edison continued work on his own "Perfected
Phonograph."
Thomas Edison was a freethinker, and was most likely a deist, claiming he did not believe in "the God of the theologians," but did not doubt that "there is a Supreme Intelligence." However, he rejected the idea of the supernatural, along with such ideas as the soul, immortality, and a personal God. "Nature," he said, "is not merciful and loving, but wholly merciless, indifferent."
Menlo Park
Thomas Edison's first light bulb used to demonstrate his invention at Menlo Park. Edison's Menlo Park Laboratory, removed to Greenfield Village in
Dearborn, MI. (Note the organ against the back wall)Edison's major innovation
was the first industrial research lab, which was built in Menlo Park, New Jersey. It was the first institution set up with the specific purpose of producing constant technological innovation and improvement. Edison was legally attributed with most of the inventions produced there, though many employees carried out research and development work under his direction.
William Joseph Hammer, a consulting electrical engineer, began his duties as a laboratory assistant to Edison in December 1879. He assisted in experiments on the telephone, phonograph, electric railway, iron ore separator, electric lighting, and other developing inventions. However, Hammer worked primarily on the incandescent electric lamp and was put in charge of tests and records on that device. In 1880 he was appointed Chief Engineer of the Edison Lamp Works. In his first year, the plant under general manager Francis Robbins Upton turned out 50,000 lamps. According to Edison, Hammer was "a pioneer of
incandescent electric lighting."
Most of Edison's patents were utility patents, which during Edison's lifetime protected for a 17 year period inventions or processes that are electrical, mechanical, or chemical in nature. About a dozen were design patents, which protect an ornamental design for a 14 year period. Like most inventions, his were not typically completely original, but improvements to prior art. The phonograph patent, on the other hand, was unprecedented as the first device to record and reproduce sounds. Edison did not invent the first electric light bulb, but instead invented the first commercially practical incandescent light. Several designs had already been developed by earlier inventors including the patent he purchased from Henry Woodward and Mathew Evans, Moses G. Farmer,[5] Joseph Swan, James Bowman Lindsay, William Sawyer, Humphry Davy, and Heinrich G?bel. Some of these early bulbs had such flaws as
extremely short life, high expense to produce, and high current draw, making them difficult to apply on a large scale commercially. In 1878, Edison applied the term filament to the element of glowing wire carrying the current, although English inventor Joseph Swan had used the term prior to this. Edison took the features of these earlier designs and set his workers to the task of creating longer-lasting bulbs. By 1879, he had produced a new concept: a high
resistance lamp in a very high vacuum, which would burn for hundreds of hours. While the earlier inventors had produced electric lighting in laboratory
conditions dating back to a demonstration of a glowing wire by Alessandro Volta in 1800, Edison concentrated on commercial application and was able to sell the concept to homes and businesses by mass-producing relatively
long-lasting light bulbs and creating a complete system for the generation and distribution of electricity.
The Menlo Park research lab was made possible by the sale of the quadruplex telegraph that Edison invented in 1874, which could send four
simultaneous telegraph signals over the same wire. When Edison asked Western Union to make an offer, he was shocked at the unexpectedly large amount that Western Union offered; the patent rights were sold for $10,000. The quadruplex telegraph was Edison's first big financial success.
Incandescent era
U.S. Patent #223898 Electric LampIn 1878, Edison formed the Edison Electric Light Company in New York City with several financiers, including J. P. Morgan and the Vanderbilt families. Edison made the first public demonstration of the incandescent light bulb on December 31, 1879, in Menlo Park. On January 27, 1880, he filed a patent in the United States for the electric incandescent lamp; it was during this time that he said, "We will make electricity so cheap that only the rich will burn candles."[6]
On October 8, 1883, the U.S. patent office ruled that Edison's patent was based on the work of William Sawyer and was therefore invalid. Litigation continued for nearly six years, until October 6, 1889, when a judge ruled that Edison's electric light improvement claim for "a filament of carbon of high resistance" was valid. To avoid a possible court battle with Joseph Swan, he and Swan formed a joint company called Ediswan to market the invention in Britain.
Other designs for a light bulb included Serbian inventor Naikola Tesla's idea of utilizing radio frequency waves emitted (in the Tesla effect) from the side
electrode plates to light a wireless bulb. He also developed plans to light a bulb with only one wire with the energy refocused back into the center of the bulb by the glass envelope with a center "button" to emit an incandescent glow. Edison's design won out during this time, although Tesla did go on to invent fluorescent lighting.
Edison patented an electric distribution system in 1880, which was critical to capitalize on the invention of the electric lamp. The first investor-owned electric utility was the 1882 Pearl Street Station, New York City. On September 4, 1882, Edison switched on the world's first electrical power distribution system, providing 110 volts direct current (DC) to 59 customers in lower Manhattan, around his Pearl Street generating station. On January 19, 1883, the first standardized incandescent electric lighting system employing overhead wires began service in Roselle, New Jersey.
Carbon telephone transmitter
In 1877 and 1878 Edison invented and developed the carbon microphone used in all telephones along with the Bell receiver until the 1980s. After
protracted patent litigation, a federal court ruled in 1892 that Edison and not Emile Berliner was the inventor of the carbon microphone. (Josephson, p146). The carbon microphone was also used in radio broadcasting and public address work through the 1920s.
War of currents
Main article: War of Currents
Extravagant displays of electric lights quickly became a feature of public events, as this picture from the 1897 Tennessee Centennial Exposition shows.George Westinghouse and Edison became adversaries due to Edison's promotion of direct current (DC) for electric power distribution over the more easily transmitted alternating current (AC) system promoted by George
Westinghouse. Unlike DC, AC could be stepped up to very high voltages with transformers, sent over thinner wires, and stepped down again at the destination for distribution to users.
Despite Edison's contempt for capital punishment, the war against AC led Edison to become involved in the development and promotion of the electric chair as a demonstration of AC's greater lethal potential versus the "safer" DC. Edison went on to carry out a brief but intense campaign to ban the use of AC or to limit the allowable voltage for safety purposes. As part of this campaign, Edison's employees publicly electrocuted dogs, cats, and in one case, an elephant[7] to demonstrate the dangers of AC. AC replaced DC in most instances of generation and power distribution, enormously extending the range and improving the efficiency of power distribution. Though widespread use of DC ultimately lost favor for distribution, it exists today primarily in long-distance high-voltage direct current (HVDC) transmission systems. Low voltage DC distribution continued to be used in high density downtown areas for many years and was replaced by AC low voltage network distribution in many central business districts. DC had the advantage that large battery banks could maintain continuous power through brief interruptions of the electric supply from generators and the transmission system. Utilities such as
Commonwealth Edison in Chicago had rotary converters which could change Dc to AC and AC to various frequencies in the early to mid 20th century. Utilities supplied rectifiers to convert the low voltage AC to DC for such DC load as elevators, fans and pumps. There were still 1600 DC customers in downtown New York City when the service was discontinued in 2005.
Media inventions
The key to Edison's fortunes was telegraphy. With knowledge gained from years of working as a telegraph operator, he learned the basics of electricity. This allowed him to make his early fortune with the stock ticker, the first
electricity-based broadcast system. Edison patented the sound recording and reproducing phonograph (or gramophone in British English) in 1878. Edison also holds the patent for the motion picture camera, although the invention itself was the work of Edison's British employee, William Dickson. In 1891, Thomas Edison built a Kinetoscope, or peep-hole viewer. This device was installed in penny arcades, where people could watch short, simple films.
篇四：英语介绍名人-比尔盖茨
Bill Gates(比尔·盖茨）
Bill Gates was born on Oct, 28 in 1955 and grew up in Seattle with his two sisters. His father was a lawyer and his mother was a teacher. Bill Gates had his elementary school and high school education is Seattle. And it was during that time Bill founded that his interests lying in writing programs and began to write programs at 13.
In 1973, Bill Gates was matriculated by Harvard but he quitted from Harvard three years later. He put all his time and energy into designing programs for Microsoft Cooperation which established in 1975 by Bill and his friend Paul Allen.
Owing to Bill’s talent and efforts, Microsoft developed rapidly and its software won more and more reputations among the publics.
What’s more, Bill is also committed to philanthropy. So far, he has donated more than 29 billion dollars to establish a fund to support medical security and education careers in the world.
Bill Gates married Melinda French Gates on Jan, 1st in 1994.They have three children .In the spare time, Bill has passion in reading books and playing golf.
比尔·盖茨(比尔·盖茨)
比尔盖茨出生在10月28日和1955年在西雅图长大和他的两个姐妹。他的父亲是一位律师,他的母亲是一名教师。比尔盖茨有他的小学和中学教育是西雅图。,这是在这段时间里,他的利益的法案成立躺在写程序,开始编写程序在13。
1973年,比尔盖茨考上了哈佛大学,但他离开哈佛大学三年后。他把他所有的时间和精力投入到设计程序对微软合作,成立于1975年由比尔和他的朋友保罗艾伦。
由于比尔的天赋和努力,微软发展迅速,其软件赢得了越来越多的声誉在公众。
更重要的是,比尔也致力于慈善事业。到目前为止,他已经捐赠了超过290亿美元来建立一个基金来支持医疗保障和教育事业在世界。
比尔盖茨结婚了梅林达法国盖茨1月1日1994年。他们有三个孩子。在业余时间,比尔有激情在看书和打高尔夫球。
Thomas Edison was a famous American scientist. He was born in 1847. When he was a child, he liked to find out how things worked. He was in school for only three months. He asked his teacher a lot of strange questions. Most of them had nothing to do with his lessons. The teacher thought the boy was not bright and was not worth teaching. When he told this to Edisons mother,she took her son out of school. As she had been a teacher,she taught him herself. The boy read a lot. Soon he became very interested in science. At the age of ten, Edison had already built a chemistry lab for himself. Ever since then, he never stopped searching for new and better ways to do things.
Thomas Edison was born on February 11, 1847 and died on October 18, 1931. H
e was an inventor and businessman who developed many important devices.
Edison is considered one of the most prolific inventors, holding a record 1,093 patents in his name.
Most of these inventions were not completely original but improvements of earlier patents, and were actually works of his numerous employees.
Nevertheless, Edison received patents worldwide, including the United States, United Kingdom, France, and Germany. Edison started the Motion Picture Patents Company, which was a conglomerate of nine major film studios.
托马斯·爱迪生是一个著名的美国科学家。他生于1847年。当他还是个孩子的时候,他喜欢发现事物如何运作。他只在学校读了三个月。他问他的老师很多奇怪的问题。他们中的大多数和他的功课无关。老师认为这个男孩是不亮和不值得教学。当他告诉这爱迪生年代的母亲,她带她的儿子离开学校。她是一个老师,她教会了他自己。这个男孩读了很多。很快他就变得非常对科学感兴趣。在他10岁的时候,爱迪生已经为自己建了一个化学实验室。从那时起,他从未停止过寻找新的和更好的做事方法。
爱迪生出生在1847年2月11日,死于1931年10月18日。他是一位发明家和商人发达许多重要设备。 爱迪生被认为是最多产的发明家之一,共有1093项专利的名字。
大多数的这些发明都不是原创,但早期的改进专利,实际上是他的众多员工的作品。
然而,爱迪生收到专利在世界范围内,包括美国、英国、法国和德国。爱迪生开始电影专利公司,这是一个集团的九个主要电影制片厂。
篇五：激光测距_外文翻译
Laser rangefinder
A long range laser rangefinder is capable of measuring distance up to 20 km; mounted on a tripod with an angular mount. The resulting system also provides azimuth and elevation measurements.
A laser rangefinder is a device which uses a laser beam to determine the distance to an object. The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender. Due to the high speed of light, this technique is not appropriate for high precision sub-millimeter measurements, where triangulation and other techniques are often used.
Pulse
The pulse may be coded to reduce the chance that the rangefinder can be jammed. It is possible to use Doppler effect techniques to judge whether the object is moving towards or away from the rangefinder, and if so how fast.
Precision
The precision of the instrument is determined by the rise or fall time of the laser pulse and the speed of the receiver. One that uses very sharp laser pulses and has a very fast detector can range an object to within a few millimeters.
Range
Despite the beam being narrow, it will eventually spread over long distances due to the divergence of the laser beam, as well as due to scintillation and beam wander effects, caused by the presence of air bubbles in the air acting as lenses ranging in size from microscopic to roughly half the height of the laser beam's path above the earth.
These atmospheric distortions coupled with the divergence of the laser itself and with transverse winds that serve to push the atmospheric heat bubbles laterally may combine to make it difficult
to get an accurate reading of the distance of an object, say, beneath some trees or behind bushes, or even over long distances of more than 1 km in open and unobscured desert terrain.
Some of the laser light might reflect off leaves or branches which are closer than the object, giving an early return and a reading which is too low. Alternatively, over distances longer than 1200 ft (365 m), the target, if in proximity to the earth, may simply vanish into a mirage, caused by temperature gradients in the air in proximity to the heated surface bending the laser light. All these effects have to be taken into account.
Calculation
The distance between point A and B is given by
D=ct/2
where c is the speed of light in the atmosphere and t is the amount of time for the round-trip
between A and B.
where is the delay which made by the light traveling and is the angular frequency of optical modulation.
Then substitute the values in the equation D=ct/2,D=1/2 ct=1/2 c·φ/ω=c/(4πf) (Nπ+Δφ)=c/4f (N+ΔN)=U(N+)
in this equation, U stands for the unit length.
Δφ stands for the delay part which does not fulfill π.
ΔN stands the decimal value.
Discrimination
Some instruments are able to determine multiple returns, as above. These instruments use waveform-resolving detectors, which means they detect the amount of light returned over a certain time, usually very short. The waveform from a laser pulse that hits a tree and then the ground would have two peaks. The first peak would be the distance to the tree, and the second would be the distance to the ground.
Using wavefront sensing, it is possible to determine both the closest and the farthest object at a
given point. This makes it possible for aircraft-mounted instruments to see "through" dense canopies[clarification needed Please explain how lasers see through canopies] and other semi-reflective surface such as the ocean, leading to many applications for airborne instruments such as:
1. Creating "bare earth" topographic maps - removing all trees
2. Creating vegetation thickness maps
3. Bathymetry(measuring topography under the ocean)
4. Forest firehazard
Technologies
Time of flight - this measures the time taken for a light pulse to travel to the target and back. With the speed of light known, and an accurate measurement of the time taken, the distance can be calculated. Many pulses are fired sequentially and the average response is most commonly used. This technique requires very accurate sub-nanosecond timing circuitry.
Multiple frequency phase-shift - this measures the phase shift of multiple frequencies on reflection then solves some simultaneous equations to give a final measure.
Interferometry - the most accurate and most useful technique for measuring changes in distance rather than absolute distances.
Applications
Military
An American soldier with a GVS-5 laser rangefinder.
A Dutch ISAF sniper team displaying their Accuracy International AWSM .338 Lapua Magnum rifle and Leica/Vectronix VECTOR IV laser rangefinder binoculars.
Rangefinders provide an exact distance to targets located beyond the distance of point-blank shooting to snipers and artillery. They can also be used for military reconciliation and engineering.
Handheld military rangefinders operate at ranges of 2 km up to 25 km and are combined with
binoculars or monoculars. When the rangefinder is equipped with a digital magnetic compass (DMC) and inclinometer it is capable of providing magnetic azimuth, inclination, and height (length) of targets. Some rangefinders can also measure a target's speed in relation to the observer. Some rangefinders have cable or wireless interfaces to enable them to transfer their measurement(s) data to other equipment like fire control computers. Some models also offer the possibility to use add-on night vision modules. Most handheld rangefinders use standard or rechargeable batteries.
The more powerful models of rangefinders measure distance up to 25 km and are normally installed either on a tripod or directly on a vehicle or gun platform. In the latter case the rangefinder module is integrated with on-board thermal, night vision and daytime observation equipment. The most advanced military rangefinders can be integrated with computers.
To make laser rangefinders and laser-guided weapons less useful against military targets, various military arms may have developed laser-absorbing paint for their vehicles. Regardless, some objects don't reflect laser light very well and using a laser rangefinder on them is difficult. 3-D Modelling
This LIDAR scanner may be used to scan buildings, rock formations, etc., to produce a 3D model. The LIDAR can aim its laser beam in a wide range: its head rotates horizontally, a mirror flips vertically. The laser beam is used to measure the distance to the first object on its path.
Laser rangefinders are used extensively in 3-D object recognition, 3-D object modelling, and a wide variety of computer vision-related fields. This technology constitutes the heart of the so-called time-of-flight 3D scanners. In contrast to the military instruments described above, laser rangefinders offer high-precision scanning abilities, with either single-face or 360-degree scanning modes.
A number of algorithms have been developed to merge the range data retrieved from multiple angles of a single object to produce complete 3-D models with as little error as possible. One of the advantages that laser rangefinders offer over other methods of computer vision is that the computer does not need to correlate features from two images to determine depth information as in stereoscopic methods.
Laser rangefinders used in computer vision applications often have depth resolutions of tenths of millimeters or less. This can be achieved by using triangulation or refraction measurement techniques as opposed to the time of flight techniques used in LIDAR.
Forestry
Laser rangefinder TruPulse used for forest inventories (in combination with Field-Map technology)
Special laser rangefinders are used in forestry. These devices have anti-leaf filters and work with reflectors. Laser beam reflects only from this reflector and so exact distance measurement is guaranteed. Laser rangefinders with anti-leaf filter are used for example for forest inventories. Sports
Laser rangefinders may be effectively used in various sports that require precision distance measurement, such as golf, hunting, and archery. Some of the more popular manufacturers are: Opti-logic Corporation, Bushnell, LaserTechnology, Trimble, Leica, Newcon Optik, Nikon, and Swarovski Optik.
Industry production processes
An important application is the use of laser Range finder technology during the automation of stock management systems and production processes in steel industry.
Safety
Laser rangefinders for consumers are laser class 1 devices and therefore are considered eyesafe. Some laser rangefinders for military use exceed the laser class 1 energy levels.
History
Development of the methods used in modern printed circuit boards started early in the 20th century. In 1903, a German inventor, Albert Hanson, described flat foil conductors laminated to an insulating board, in multiple layers. Thomas Edison experimented with chemical methods of plating conductors onto linen paper in 1904. Arthur Berry in 1913 patented a print-and-etch
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