Deceased--Tingye Li

Tingye Li
July 7th, 1931 to December 27th, 2012

"Tingye Li Dies at 81; Played Crucial Role in Laser’s Development"

by

Douglas Martin

January 6th, 2013

The New York Times

Tingye Li, an electrical engineer whose calculations in the early 1960s helped guide the development of the laser and propel the dizzying increase in the speed of fiber-optic communication, died on Dec. 27 in Snowbird, Utah. He was 81.

The cause was a heart attack while he was on a family ski trip, his family said. He lived in Boulder, Colo.

Lasers were in the early stage of development when Dr. Li and a colleague at Bell Labs, A. Gardner Fox, developed a computer simulation of how lasers produce the focused light energy that has transformed fields from medicine to space travel. They reported their findings in a paper published in 1961.

Dr. Arno Penzias, a former director of Bell, called their paper a tool kit for subsequent designers of lasers and other optical systems. He said it helped transform the “wonderful invention” of the laser — the word is an acronym for light amplification by stimulated emission of radiation — into “a practical communications platform.”

In essence, the researchers provided a mathematical model for how light bounces about inside a laser between two mirrors as it gathers energy, predicting factors like the shape and intensity of light beams. Alan Willner, an electrical engineering professor at the University of Southern California, called the work “the foundational teaching” on the innards of lasers.

“There aren’t many papers that help define a field, but this was one of them,” he said in an interview.

The research that led to nearly instantaneous communication by light waves was itself snail-like. Dr. Li and Dr. Fox had to write their own programs, punching them into decks of cards, for a room-size computer that was less powerful than a palm-size calculator today. The computer ran the program for two or three hours. A frequent error message meant that the researchers had to scour the cards for a single improperly punched letter, Jeff Hecht wrote in “Beam: The Race to Make the Laser” (2010).

Bell Labs was virtually unchallenged as the largest and most inventive laboratory in the world, having a hand in many of the 20th century’s most important inventions. Dr. Li, who wrote or helped write more than 100 papers, patents and books, led research teams at Bell for more than three decades.

Some of their work laid the groundwork for today’s broadband. One area of study was in finding ways to use light waves to convey information on optical fiber rather than copper wire or radio waves. Another team Dr. Li led developed optical amplifiers, which amplify an optical signal directly without the need to first convert it into an electrical signal.

Dr. Li was an early proponent of using the rare earth metal Erbium in the amplifiers, an improvement that helped raise their capacity more than a hundredfold.

“Tingye Li has shaped the lightwave network infrastructure we know today,” the Institute of Electrical and Electronics Engineers said when presenting him with its Edison Medal in 2009.

Li Ding Yi, as his name is transliterated from Chinese, was born in Nanking, China, on July 7, 1931. His mother, Lily, belonged to the first generation of Chinese women to receive a modern higher education. She became an activist for women’s rights.

His father, Chao, was a Chinese diplomat who was consul general in Vancouver, where Tingye attended middle school, and was later posted to South Africa, where Tingye earned an undergraduate degree in electrical engineering from the University of Witwatersrand. He earned a Ph.D. in electrical engineering from Northwestern University in Evanston, Ill.

Dr. Li joined the Bell Telephone Laboratories (later AT&T Bell Laboratories) in 1957 and worked there until 1998. He worked there with the Nobel Prize recipients Charles Hard Townes and Arthur L. Schawlow, who together invented the maser, which amplified microwaves the way lasers would soon amplify light.

“There was a lot going on and a lot of people helping each other,” Dr. Penzias said.

Dr. Li often quoted Confucius, though friends suspected he occasionally concocted his own learned sayings and then attributed them to the sage. He frequently went to China to help it develop optical communications. The Chinese Academy sent his family a letter at his death praising him for helping China “leapfrog to a higher level” in handling telecommunications traffic.

Dr. Li is survived by his wife of 56 years, the former Edith Wu; his daughters, Deborah Li Cohen and Kathryn Li Dessau; and four grandchildren.

In a speech on his 80th birthday, Dr. Li revealed that he had proposed marriage to his wife for their next life, after they are both reincarnated. She tentatively agreed, he said, if he behaved.

"OSA Mourns the Loss of Tingye Li, 1931-2012, OSA Past President"

Tingye Li, an OSA Past President and Fellow Emeritus renowned for his contributions to lightwave technology and optical fiber communications, died on 27 December 2012 in Snowbird, Utah, USA.  He was 81.

Born in 1931 in Nanjing, Jiangsu Province, China, Li obtained his bachelor’s degree from the University of Witwatersrand, South Africa, and his Ph. D. from Northwestern University, USA.  He joined Bell Telephone Laboratories (later AT&T Bell Laboratories) in 1957, and worked there for 41 years until his retirement in 1998.

During his career at AT&T, Dr. Li authored and coauthored more than 100 journal papers, patents, and books in the areas of antennas, microwave propagation, lasers and optical communications.  He made significant contributions in the fields of lightwave technologies and systems, and he spearheaded research on wavelength division multiplexing transmission systems that revolutionized long-distance telecommunication networks.

In 1961, he and his colleague A. Gardner Fox published a now-classic paper on laser resonator modes, Resonant modes in a maser interferometer, that established the basis for the understanding of the design of optical resonators and how modes in optical resonators behaved.  In the late 1980s, when the whole world’s attention on optical communication was still focused on a single-channel high speed solution, Li and his team at AT&T Bell Labs developed the world’s first (sparse channel) WDM (Wavelength Division Multiplexing) system.  Their experiment in 1992 at Roaring Creek turned out to be a "roaring success" as Li claimed in an interview, allowing 2.5 Gbit/s transmission per channel, the highest rate available at the time. The use of WDM and optical amplifiers changed the paradigm of network economics and is considered to be of revolutionary significance (though evolutionary in design) in the history of lightwave communications.

An OSA member since 1966, Li was named an OSA Fellow in 1977.  He served as an At-Large member of the OSA Board of Directors from 1985-1987, as OSA President in 1995, chaired numerous committees, and was a leader in building the Asia Communications and Photonics (ACP) conference.

Li received many awards and honors during his long and distinguished career.  He was a Fellow of the Institute of Electrical and Electronics Engineers (IEEE), the American Association for the Advancement of Science (AAAS), the Photonic Society of Chinese-Americans, and the International Engineering Consortium.  He was also a member of the U.S. National Academy of Engineering and the Academia Sinica (Taiwan), and a Foreign Member of the Chinese Academy of Engineering.

Li was the recipient of OSA’s John Tyndall Award (1995) and OSA's Frederic Ives Medal/Jarus W. Quinn Prize (1997); IEEE’s W.R.G. Baker Prize (1975), David Sarnoff Award (1979), Photonics Award (2004), and Edison Medal (2009); and the 1997 AT&T Science and Technology Medal.  He was given the 1981 Alumni Merit Award from Northwestern University, and he received Achievement Awards from the Chinese Institute of Engineers/USA (1978), the Chinese-American Academic and Professional Society (1983), and the Photonics Society of Chinese-Americans (1998).  Li was named an honorary professor at many universities in China, including Tsinghua University, Shanghai Jiaotong University, Beijing University of Posts and Telecommunications, Beijing Jiaotong University, Fudan University, Nankai University, Tianjin University, the University of Electronic Science and Technology of China, and Qufu Normal University. He was also named an honorary professor at National Chiao Tung University and National Taiwan University, and he was granted an honorary Doctor of Engineering degree by National Chiao Tung University in Taiwan.

Li was respected and loved as an “elder” among young scientists and engineers in the field of photonics, both for his immeasurable contributions to the field and for his willingness to spend time mentoring, advising, promoting, and encouraging young people.

Tingye Li is survived by his wife, Edith Wu, daughters Deborah (David Cohen) and Kathryn (Daniel Dessau), and several grandchildren.  A memorial service for family, friends and colleagues is being planned for a future date.

Tingye Li [Wikipedia]

Do I smell a challenge in the streets of Dodge City?

Ole "Dead Eye" Curiosity honing its skills. How soon will it be before toy companies market the goodies. WOW, NASA will make millions on royalties.

"Before-and-After Photos: Curiosity’s Laser Burns Holes in Martian Rock"

by

Adam Mann
  
August 30th, 2012

Wired

When it comes to laser blasts, the Curiosity rover is no slouching Stormtrooper. These impressive before-and-after shots show a nice row of dots resulting from the probe’s Chemistry and Camera (ChemCam) instrument on a target patch of soil on Mars.

Burning tiny holes in this unlucky bit of Martian dirt — which NASA engineers nicknamed “Beechy” — is called a five-by-one raster. The technique provides data about changes in chemical composition over small areas of the regolith. Each image covers a circular view about three inches wide.

ChemCam is Curiosity’s coolest bit of science gear, shooting laser beams that deliver a million watts of power for about five one-billionths of a second. The rover analyzes the resulting glowing plasma to determine what elements and molecules make up its target. Beechy received 50 laser shots, creating holes ranging from 0.08 to 0.16 inches wide, and demonstrated the rover’s ability to clear dust and small grains from its target area.

Chemical analysis showed that the rocks in this sample look unsurprisingly similar over such a short distance, but the small amount of variability will help scientists with future studies. This is not the first time that Curiosity has shot its ChemCam laser — a previous rock, Coronation, was at the receiving end of the rover’s might 11 days ago.

Deceased--William R. Bennett Jr.

William R. Bennett Jr.
January 30th, 1930 to June 29th, 2008


"William R. Bennett, 78, Pioneer in Gas Lasers, Dies"

by

Jeremy Pearce

July 7th, 2008

The New York Times

William R. Bennett Jr., a physicist and inventor who helped develop a gas laser in the 1960s in technology that later revolutionized surgery and made possible compact-disc players and grocery-store scanners, died on June 29 at his home in Haverford, Pa. He was 78.

The cause was cancer of the esophagus, his family said.

In the late 1950s, while working at Bell Laboratories in Murray Hill, N.J., Dr. Bennett and a small scientific team assembled a gas laser, the first of its kind able to send out a continuous beam of red light.

The team, which included Donald R. Herriott and Ali Javan, trapped helium and neon in a pressurized tube and agitated the gases’ atoms with an electrical current. Internal mirrors at each end of the tube redirected the resulting particles of light to send them out in a concentrated and continuous beam.

The helium-neon gas laser described by Dr. Bennett and the team in the journal Physical Review Letters in 1961 represented a departure from an earlier laser, which derived its beam from a solid material, synthetic ruby.

Gas lasers have some advantages over those using ruby and other solid materials. For example, although both types are in wide use, gas lasers allow heat to disperse from the laser’s tube relatively rapidly. Dr. Javan and Dr. Bennett received a patent for the gas laser in 1964.

In following years, Dr. Bennett and others experimented with argon, krypton, xenon and similar gases and studied the qualities and burning power of their laser beams. Gas lasers have been used in construction and surveying and to cut or weld materials for industrial applications.

Lasers have also profoundly altered eye surgery and are now commonly used to modify precisely the shape of the cornea and sharpen vision and to halt the progress of macular degeneration and other ocular diseases.

Dr. Bennett left Bell Laboratories and in 1962 joined the newly formed department of physics and applied science at Yale. There, he continued his laser research, studied musical sound, and looked into possible health effects of power lines and electromagnetic fields, a risk he believed to be significantly overrated.

William Ralph Bennett Jr. was born on Jan. 30, 1930, in Jersey City. He graduated from Princeton, then received a doctorate in physics from Columbia in 1957.

In 1964, he was named a professor of physics and applied science at Yale, and remained there for the rest of his career. Dr. Bennett became a professor emeritus of engineering, applied science and physics in 1998. From 1981 to 1987, he was master of Silliman College at Yale.

Among his publications, Dr. Bennett wrote a book, The Physics of Gas Lasers (1977). He also wrote a textbook, Introduction to Computer Applications for Non-Science Students (1976), that was an early resource in its field.

Dr. Bennett is survived by his wife, the former Frances Commins. The couple were longtime residents of New Haven, and moved to Haverford in 2000. He is also survived by a son, Bill, of Berkeley, Calif.; two daughters, Nancy of Los Angeles and Jean of Bryn Mawr, Pa.; a sister, Carol Anne Valles of Bedford, N.Y.; and five grandchildren.

In the 1970s, Dr. Bennett introduced a popular undergraduate course for humanities and social-science students at Yale, intended to show the problem-solving promise of nascent computers.

A colleague, Werner P. Wolf, a professor emeritus of engineering and applied science at Yale, said the course proved to be both prescient and persuasive, and "made the whole concept of computers exciting."

Part of the course, Dr. Wolf said, was dedicated to practical challenges; Dr. Bennett told his students to calculate the ballistics of catapulting frozen loaves of bread across the New Haven campus.

Yale was a little late, but...

"Physicist Bennett dies"

by

Raphael Shapiro

September 8th, 2008

Yale Daily News

William R. Bennett Jr., former Yale professor, master of Silliman College and groundbreaking physicist, died June 29 of esophageal cancer at his home in Haverford, Pennsylvania. He was 78.

"The human body is like a machine," Bennett's son William remembered his pragmatic father saying many years ago. "Parts wear out."

Bennett was born January 30, 1930 in Jersey City, New Jersey to physicist William Bennett and Viola Schreiber.

Bennett and his wife of nearly 56 years, Frances, were members of the Yale community for 38 of them. He became a tenured professor in 1962, and was Silliman’s master from 1981 to 1987. He taught popular courses on the physics of music and the computer as a research tool, for which he was named one of Yale's top ten professors for many years in a row. He and his wife retired to Pennsylvania in 2000 to be closer to his eldest daughter Jean and her family.

Bennett, the C. Baldwin Sawyer Professor Emeritus of Engineering and Applied Science and Physics, may be best known for his pioneering role in the invention of the first gas laser in 1960 at Bell Laboratories. Although this first laser used helium and neon, Bennett’s research on spectroscopy and collisions of the second kind continued with other noble gases such as argon, krypton and xenon.

Bennett has left a far-reaching legacy, one visible in everything from CD players to grocery store scanners to nearly every fight sequence in Star Wars.

His argon laser provided the first and, to this day, most effective prevention of blindness in diabetes and is still the most widely used laser in all eye surgeries. Bennett himself benefited from his invention when an argon laser was used to repair his detached retina.

On Saturday, friends, family, colleagues and acquaintances braved the rain to fill the Silliman Common Room in a memorial service dedicated to the prolific physicist. They did not gather to laud his scientific achievements, as impressive as they were. Instead the crowd came to listen to heartwarming, often humorous stories about a beloved husband and father, an amiable and charismatic man.

Bennett's son, also William, said jokingly to a standing room-only crowd before the start of the service, "We had no idea Dad had so many friends."

"He had a lot more than this," someone in the crowd replied.

"Well it's a good thing we had bad weather," William quipped.

Most of those who spoke at the gathering touched upon Bennett’s passion for music. Eugene Commins, Frances Bennett’s brother, read a letter sent from Bennett’s younger sister Carol Ann Bennett Valles, who was unable to attend the ceremony. In it, she wrote that she still remembers the sound of applause after a clarinet solo he performed as an undergraduate at Princeton.

"He could have been a professional musician," she wrote. "But maybe it's better for physics that he was not."

Music was always a great passion of Bennett's.

"Music was my dad's religion," said son William, now the principal oboist in the San Francisco Symphony Orchestra.

The family recounted numerous stories of the role it played in their lives, from chamber music sessions in the living room, to a harsh dinnertime critique of a confiscated copy of "Sergeant Pepper's Lonely Hearts Club Band," to his first "organ transplant," when he installed a full pipe organ in the summer home he built in Colrain, Massachusetts.

At the time of his death, Bennett had completed around one thousand pages — 75 percent — of a new manuscript entitled "The Science of Musical Sound." Commins, who together with Bennett was a graduate student in the physics department at Columbia in the early 1950s, said upon reviewing the hundreds of equations in the text, he could not find a single error.

Robert von Gutfeld, a senior research scientist in the chemical engineering department, often accompanied Bennett on cello.

"He was an icon of everything the world could possibly want," he said.

At the end of the memorial service, William played a crackly recording of that Princeton solo, Mozart's Concerto for Clarinet and Orchestra in A Major.

Those in the crowded common room Saturday hung on every note, remembering a teacher and friend.

Bennett is survived by his wife Frances, children Jean, William, and Nancy, sister Carol Ann, five grandchildren and a German shepherd named Bartok.