Published in oemagazine, August 2005.
H. John Caulfield's lifetime of curiosity for all things scientific has resulted in 27 patents, hundreds of publications, and immeasurable inspiration to the optics community. This year that inspiration will be acknowledged when Caulfield receives the Gold Medal of the Society at SPIE's 50th Anniversary Banquet on 3 August in San Diego, CA.
His early career took an unplanned path when his PhD advisor at Iowa State University (Ames, IA) told him he should go into academia, because he was "too smart for industry." Caulfield, negatively inspired by the advice, made it a point to pursue an industrial career, going to work for the Central Research Laboratory at Texas Instruments (Dallas, TX).
"They had me try to improve the thermionic energy converters, an invention of a Hungarian scientist named Dennis Gabor," he says. But after a few years, the company abandoned that line of research and directed Caulfield into optics. He also became their seminar chairman, in charge of arranging in-house presentations on technical topics. He had read an article in Scientific American on holography, and invited its author, Emmett Leith, to come and give a talk.
Holography, Caulfield says, "looked interesting, and I was amused to find Dennis Gabor re-entering my life."
Leith recalls that trip to Texas, and how he and his family hit it off with Caulfield. "We had a great time, which I will never forget," He says. "Little did I suspect that this was the beginning of a relation that would last for these past 40 years and hopefully for many more to come."
Leith went on to become a legend in the world of holography, and Caulfield one of its most active promoters.
Caulfield's research interests evolved as the technology did. "Over time," he says, "holography led to coherent optics, that led to optical computing, that led to optical and then other kinds of neural networks, that led to cognitive science and its biomimetic counterparts, that led to evolution and many other things I now do research in."
Back to School
He returned to the academic world in 1985 when he became director of the new Center for Applied Optics at The University of Alabama in Huntsville, a post he held until 1996. Now he juggles two academic posts--as program manager and chief scientist at Alabama A&M University Research Institute (Huntsville, AL), and distinguished research professor of physics at Fisk University (Nashville, TN). Both are historically African-American universities, and Caulfield is motivated "to help an underrepresented part of America get more involved in high tech."
"I grew up in Texas during the Civil Rights Movement. I marched and protested a little, but nothing substantive. But at least I had begun to understand from all sides what segregation had done to us." Caulfield says that the role of Fisk and Alabama A&M is "to allow people who might otherwise be shut out from good jobs a chance to reach their full potential."
Holography has been "the stimulant that created great interest in many other fields that no longer need it," he says. "Synthetic aperture signal processing, 3-D display, Fourier correlation, and the like. Even its successes have done so well that the fields they led to no longer remember that they had holographic origins." Optical coherence tomography, for example, originated in the mid-sixties with independent work by Denisyuk, Leith, and Caulfield.
Caulfield sees many holographic technologies finally coming into their own. Ultrasonic holograms for 3-D medical imaging are taking off, he says. And at the other end of the spectrum, x-ray holograms are finally useful. It's now economical to make huge, efficient holograms for displays, solar daylighting, and other applications.
"In short, so long as young, clever scientists come into the field, and the giants of the field--Leith, Denisyuk, Lohmann, et al.--keep stimulating all of us, the future is bright and wide open."
Caulfield with his wife, Jane, on their "Far Out Farm."
Caulfield's two current projects are artificial visual perception and conservative optical logic devices. "I want to let machines see the world as we do: as smooth, moving, identified things," he says.
"Optical logic has been fun for 40 years but only valuable lately with semiconductor optical amplifier-based devices. I am trying to open up a new niche for useful optical logic. My devices cost neither energy nor bandwidth. They can implement any Boolean function and even change functions. But if you try to cascade them, most of those advantages disappear. Finding the right niches, creating the right logic, and so forth, is great fun."
Caulfield's approach to a challenge is a bit unorthodox, according to John L. Johnson, command group science advisor for U.S. Army Europe (Heidelberg, Germany), who collaborated with him on numerous projects in the '90s.
"John has the most non-geometrical mind of any scientist I have ever known," Johnson says. (See sidebar below.)
Caulfield first joined SPIE in 1970, and served in many roles including Secretary, Symposia Vice President, and editor of SPIE's flagship journal, Optical Engineering. Having participated in more than half of the Society's first 50 years, he returns to the idea of inclusiveness as the key to the future.
"To me, this is the genius of SPIE. For example, we could absorb exobiology when Richard Hoover suggested it. We can discuss bug eyes (for biomimetic systems) in one room and ‘bug-eyed monsters' in another, and the participants can commingle and help one another."
Caulfield lives midway between the two universities he's affiliated with, at "Far Out Farm," a sheep ranch run by his wife, Jane, and daughter Kim. Another daughter, Cindy, is a clinical and research oncologist. According to long-time friend and research colleague R. Barry Johnson, Caulfield can sometimes be found "mucking out the barn" as a form of therapy.
The Gold Medal of the Society is meaningful because "friends and colleagues have gone out of their way to tell me that I have made their careers in optics more enjoyable," he says. "Optics is a community of people bound together by the sheer joy of working in this still-young field. It is the people even more than the ideas that make it so much fun. I thank them, and this time they thanked me."
(l to r) 1979-1980 President Robert R. Shannon, Technical Director Yale Katz, Executive Director Joe Yaver, Symposia Chair Andrew G. Tescher, Secretary H. John Caulfield, and volunteer Bruce Steiner gathered at SPIE headquarters in Bellingham, WA, in March 1979.
The Caulfield Approach
John drew a circle on the board. "This is the area of all of the knowledge Man has discovered," he said. Then he put a dot on the board, located far outside the circle. "By processes of creativity, perhaps the subconscious, or by some inspiration, we have a new idea, and it is out here, not connected to the general body of knowledge. So we jump, landing in this new place apart from all that we have known before. What do we do?" John then drew a long wavering extension from the isolated point back to the big circle. "We reason our way back, and connect our idea to everything else." Then John smiled and drew an arrow pointing from the body of knowledge to the new point. "But what we publish is this," he said, "the logical path that steps us to the new place in well-connected links. Everyone thinks we did it by extraordinary reasoning, plodding across one tightly-reasoned link to the next, while in fact we soared across the empty space!" What John did not say was that when most people soar, they land in places that you can't connect back to the big circle. John's flights land in the right places, and that is one of his great gifts.
- John L. Johnson