Reflections: Roland V. Shack

April 12, 2016
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Roland Shack Portrait

Professor Emeritus Roland V. Shack’s multiple talents and contributions to the field of optics are legendary. His name has been widely spread in publications and reports, making the Shack-Hartmann Sensor and the Shack Cube Interferometer “household words.” But, for many, Roland’s dedication to his students and the learning process is considered one of his greatest influences on the optics community.

Early Life

Roland was born in Chicago, Illinois on 15 January 1927 where he lived with his parents, Vincent and Fiore, and his younger brother, Bill, until 1934 when the family moved to Washington, D.C. Even in his earliest years, Roland exhibited creativity, patience and persistence, which have been characteristic traits throughout his life. 

At the age of seven, after being taught to play the violin by his uncle, Roland was chosen to perform at the 1934 Chicago “Century of Progress” World’s Fair in the Chicago Symphony Children’s Orchestra. Although this performance was the culmination of his career as a violinist, Roland has continued to love music and playing the piano throughout his life.

The summer of Roland’s 16th year, he headed to northern Idaho to handpick plants infected with blister rust for the U.S. Forest Service. By this time, Roland had already begun to combine science and art. He wrote several letters to his parents containing detailed illustrations of the flora and fauna he had observed. 

Roland graduated from Washington & Lee High School in Arlington, Virginia in 1944. He was awarded both a Bausch & Lomb Honorary Science Award and a full scholarship to Massachusetts Institute of Technology. However, knowing he was going to be drafted, he enlisted in the United States Army Signal Corps. 

During his time of service, Roland completed two years of college while attending Carnegie Tech, Virginia Military Institute and Virginia Polytechnic Institute. Upon his discharge in 1945, Roland contacted MIT regarding admission and was told that although his scholarship would be honored, there would be a two to three-year wait due to the high number of returning veterans enrolling.

Roland playing piano

At the urging of a friend, whose father was a professor at the University of Maryland, Roland headed to College Park, Maryland to study physics and art, earning a Bachelor of Science in Physics in 1949. Two years later, he earned a Bachelor of Arts in Fine Arts from American University in Washington, D.C. In years to come, Roland would seamlessly merge science with art, both personally and as a consultant to numerous artists striving to understand the optical properties of color and the nature of light.

Early Career

Roland’s path to a career in academia began as a junior scientist at the National Bureau of Standards in the early 1950s. He pursued his interest in image formation and evaluation and considers himself a “minor pioneer” in the development of the optical transfer function. But, although Roland garnered a certain amount of satisfaction from his work, he began to question whether people really understood his research and if he was making a difference in the world.

While living in the D.C. Metro area, Roland continued to pursue his love of art by sculpting. He also designed and built sets and lighting for Theatre Lobby, a local theatre company located in a carriage house behind St. Matthew’s Cathedral. It was there that he met and fell in love with a young stagehand, Pamela Thresher. Roland and Pam were married in August 1957.

Roland at Perkin-Elmer

That same year, Roland accepted an offer of employment as an engineer at the Perkin-Elmer Corporation in Norwalk, Connecticut. He and Pam moved to New York City, where Pam attended New York University. At Perkin-Elmer, Roland worked on design and manufacturing problems for numerous programs including the Stratoscopes I and II, balloon-borne astronomical telescopes and Satrack, the Baker-Nunn satellite-tracking camera. Managers at Perkin-Elmer quickly discovered and utilized Roland’s gift for teaching and mentoring other engineers.

In 1960, Roland’s mentor Rod Scott talked with Roland about pursuing a Ph.D., with the ultimate goal of becoming a professor of optics. With the generosity of Perkin-Elmer, who awarded Roland a two-year grant to cover his expenses, Pam and Roland moved to the United Kingdom, where both studied at Imperial College, University of London. For Roland, working under the direction of Professor H. H. (Harold) Hopkins was the fulfillment of a dream. In 1963, with all of his coursework finished, and just needing to write and defend his dissertation (completed and Ph.D. awarded in 1965), Roland and Pam headed back to Connecticut and Perkin-Elmer.

Westward Bound

Once back at Perkin-Elmer, Roland resumed his engineering work and, with the encouragement of Rod Scott and Harry Polster, explored university-level teaching positions in optics. Meanwhile, in Tucson, Arizona, Dr. Aden B. Meinel, Director of the Astronomy Department at the University of Arizona and Chair of the U.S. Needs in Optics Committee, had been given six weeks to create a proposal for the design, construction and equipping of the laboratory and research areas required for an Optical Sciences Center, OSC, at the University of Arizona.

Aden had an occasion to talk at Perkin-Elmer with Dick Perkin, President of the company, and Rod Scott about how the plans for the center were developing. The story was that, out of the blue, Dick asked Aden if he would like Roland to join him in Tucson. Aden, as a Perkin-Elmer consultant, had worked with Roland on some of the company’s projects. Already much impressed by Roland’s grasp of both theory and practice, Aden’s answer was a resounding “Yes!”

vw beetle

August 29, 1964 - A Half Century Ago Today!! Roland, Pam and 9-month old David drive into Tucson, Arizona in their 1963 VW Bug. Roland is eager to start a new career as an academic — one of the first two faculty members hired to help Dr. Aden Meinel begin the University of Arizona’s Optical Sciences Center. It is hot, we have no air-conditioning in the car, and we’ve just crossed a rickety bridge spanning a bone-dry riverbed. We pass a convenience store on two-lane Tanque Verde Road where three saddled horses are tied up to the hitching rail. We’re truly in the Wild West!

- (Pam Shack’s Facebook post, 29 August 2014)

Academia

In the fall of 1965, OSC’s academic program began operation with five faculty members, an enrollment of four graduate students and a curriculum of seven courses. As one of the faculty, Roland discovered his “real calling” — teaching. He encouraged students to be curious, to understand what was happening before their eyes and not take anything for granted.

In the fall of 1989, OSC began offering an undergraduate degree program in optical engineering. The intent was that graduates of this program would be prepared to immediately work in industry. Roland was asked to teach a senior laboratory course and, rising to the challenge of educating future optical engineers, he designed his curriculum to be a hands-on experience modeled after real-life situations typical of those in industry, heavily laden with teamwork and practical skills. 

As director of OSC until 1973, Aden found occasions to sit in on Roland’s classes. In a letter to Roland, upon his retirement in 2002, Aden reminisced:

How easy it was to listen to you and see you make succinct drawings on the chalkboard — no overhead projectors or PowerPoint then. Some of us were hardly out of the slide rule era. I was impressed by the way your students sat on the edge of their chairs listening to you. I could see that you had a rare talent that few in the academic world could equal. I saw this dedication to students grow over the years. I can truly say that your ability to advise and mentor students has provided the key whereby many of your graduate students have moved into the senior ranks of teaching, research and management.

Simply Creative

Throughout his career, Roland strived for one thing above all else — simplicity in everything he did as a way of making a difference in the lives of others. The two inventions that bear his name, the Shack-Hartmann test and the Shack cube interferometer, bear witness to his love of simple solutions. “As you look at these two inventions you realize how simple, clever, and elegant they are,” says Professor Emeritus and Founding Dean, James C. Wyant. “They are typical Roland Shack.”

In an interview with SPIE1, upon being awarded the 2004 Gold Medal, Roland described his thought process behind two of his many contributions to optical testing — the Shack-Hartmann test and the Shack cube interferometer.

The Shack-Hartmann test

One of our contacts through the Air Force was with the Satellite Tracking Facility at Cloudcroft, New Mexico. Satellite images were of course blurred by atmospheric turbulence, and Aden [Meinel] suggested that if we siphoned off some of the light going to form the image and put it through a Hartmann screen, we might be able to reconstruct the wavefront involved in forming the image and thereby do some image processing to improve it. He asked me to look into it.

The classical Hartmann screen consists of an opaque screen with holes in it. The beams that are transmitted through the holes are intercepted by a photographic plate some distance from the screen, and the path of each beam is determined. It is a simulated ray trace.

However, the classical Hartmann test is massively inefficient in using the light incident on the screen. Because the beams diverge somewhat after passing through the screen, the holes must have adequate spacing so that the beams will not interfere with each other. The fact that the source (the satellite) is somewhat extended also increases the spot size at the photographic plate. Also, allowance must be made for the deviations of the beams as well.

I was concerned because there aren't many photons available if most of them have to form the satellite image. The first thing that occurred to me was that I could increase the recording efficiency on the photographic plate by putting a small lens in each hole to focus the light onto the plate. It then occurred to me that there was no longer need for the screen between the holes. The lenses could be butted up against each other.


The Shack Cube Interferometer

Back when I was working at NBS I wanted to make what I called an Autostigmatic Microscope. This involved putting a beamsplitter between the objective and the eyepiece of a microscope with an illuminated pinhole on the side of the beamsplitter so that light from the pinhole would be focused on a reflective surface by the objective and returned through the beamsplitter to the eyepiece. 

When I tried this, the return beam was surrounded by a large halo of light from the reflection at the output surface of the beamsplitter, and it occurred to me that if I cemented a lens on that surface such that the pinhole was at the optical center of curvature of the surface, that ghost image would be in focus on the eyepiece side, providing a reference for the return beam from the objective and eliminating the need for a cross-hair.

Years later, at the Optical Sciences Center, I designed a null corrector for an astronomical mirror we were making, and a critical part of that null corrector was an autostigmatic cube to establish the axis. The pinhole was of course illuminated by a laser because of its efficiency and brightness. The light from the null corrector goes to the mirror under test, and the alignment consists of pointing the corrector so that the return image is free of coma.

I had a student working with me and I asked him to look through the eyepiece and tell me what the coma looked like as I made the adjustments. He was estimating the magnitude in wavelengths! I thought that was unusual, so I looked through the eyepiece myself, and discovered that, rather than focusing on the return image, he had focused on the image of the primary formed by the beamsplitter acting as a thick plano-convex lens, and thus was seeing the interference between the spot reflected by the spherical beamsplitter surface and the return image from the mirror. This could only happen with laser light.

And so the Shack cube interferometer was discovered.

Legacy

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It is hard to adequately express the important role Roland Shack played in changing a concept of an Optical Sciences Center in Arizona into a solid reality. The national and international reputation of OSC owes much to his 38 years of hard work and dedication.

But to the 47 M.S. and Ph.D. students Roland advised and countless more that he taught, what is remembered as Roland’s most important legacy is his unfailing dedication in his multiple roles of teacher, advisor and mentor and his unparalleled talent for helping those around him develop their own ideas. As described by Bob Breault, Ph.D. ’79, Roland Shack is “a bright scientist who was really born to teach others how to enjoy the process of learning.”

[Editor’s Note: Upon Roland’s retirement from OSC, Pam and Roland made a generous donation to the senior undergraduate teaching lab, which now bears his name — a true testament to Roland’s professional dedication to enriching the educational experiences of students. Later, the Roland V. Shack Graduate Student Scholarship in Optical Sciences was established in gratitude and respect for this extraordinary man. This scholarship is made possible by the generous and continued support received from family, colleagues, industry partners and former students of Professor Shack.]

 

1 Rich Donnelly. "The Simple Life." SPIE Newsroom, oemagazine, August (2004) DOI: 10.1117/2.5200408.0005