Robert G. Greenler
About Optica
In Memoriam: Robert G. Greenler, 1929 - 2025
21 September 2025
Robert G. Greenler, 1987 Optica President and recipient of the Esther Hoffman Beller Award, passed away on 21 September 2025 at the age of 95.
Born in Dunkirk, Ohio, Greenler earned his B.S. in physics from the University of Rochester and a Ph.D. from Johns Hopkins University in 1957. He joined the University of Wisconsin–Milwaukee in 1962, where his pioneering research on the optical properties of surfaces and his leadership in creating the interdisciplinary Laboratory for Surface Studies helped establish the university’s reputation in physics. He served on the faculty for three decades before becoming Professor Emeritus.
A gifted communicator, Greenler co-founded The Science Bag in 1973, a family-friendly public lecture series that drew more than 140,000 attendees over 30 years and became a model for community science outreach. His popular books, including Rainbows, Halos and Glories and Chasing the Rainbow: Recurrences in the Life of a Scientist, reflected his lifelong passion for making the beauty of optics accessible to all.
Greenler was a dedicated Optica volunteer serving on multiple committees during his tenure on the Board of Directors (1985-1988) and his term as 1987 President. In addition to his leadership with Optica, Greenler held prominent roles with the American Institute of Physics and the Council of Scientific Society Presidents. Elected an Optica Fellow in 1974, he went on to receive numerous honors recognizing both his scholarship and outreach. In 1993, he was awarded Optica’s Esther Hoffman Beller Award “for extraordinary leadership in advancing the public appreciation and understanding of science and the scientific method through his lectures and demonstrations of optics to diverse audiences, his writings, and his advocacy for science and education.” He was also recognized with the Robert A. Millikan Award, and the University of Wisconsin–Milwaukee Ernest Spaights Plaza Award.
Through his research, teaching, leadership, and outreach, he inspired generations of students, colleagues, and members of the public. His legacy of scientific excellence and dedication to sharing the wonder of optics will long be remembered.
Optica and the scientific community mourn his loss.
