Remembering Samuel M. Berman, 1933–2025: Pioneer in Energy Efficiency and Vision Science

Samuel Morris Berman, a pioneering physicist whose work transformed the science of lighting and energy efficiency, died on September 6, 2025, in Albany, California. He was 92. Berman joined Lawrence Berkeley National Laboratory (LBNL) in 1977 as a senior scientist and the founding head of its Lighting Group. Under his leadership, the group advanced understanding of how lighting affects human visual performance and how lighting and building technologies can be engineered for optimal energy performance.

Born in Worcester, Massachusetts, on February 4, 1933, Berman was a gifted musician who entered the University of Miami on a music scholarship but graduated with a degree in physics. He earned his Ph.D. in theoretical physics from the California Institute of Technology, where his dissertation was supervised by Nobel laureate Richard Feynman. Following his doctorate, he held postdoctoral appointments at the Niels Bohr Institute in Copenhagen, CERN in Geneva, and Imperial College in London. At age 29, he returned to the United States to accept a tenured position at the SLAC National Accelerator Laboratory, becoming one of Stanford’s youngest tenured professors.

In the mid-1970s, in response to the decade’s energy crisis, Berman made a dramatic career transition, leaving the frontiers of particle physics to focus on the technical foundations of energy conservation. The decision was unconventional for a physicist of his stature; his work in theoretical particle physics had earned him recognition within that community, and colleagues were astonished that he would leave a secure, tenured position at Stanford to apply his expertise to the practical challenges of energy efficiency and building science—a field that was then just emerging. He directed a study to develop an end-use energy database for creating an engineering-based model capable of predicting how appliance and building standards would affect electricity demand. In 1977, he joined LBNL full time to launch a new program in lighting and building efficiency.

Within a few years, he had transformed a small team into a $2 million annual research program that integrated physics, engineering, vision research, and human-factors science, addressing the most important challenges in energy-efficient lighting.

Under Berman’s leadership, the LBNL Lighting Group helped develop the first high-frequency electronic ballast for fluorescent lamps through rigorous performance testing. This breakthrough in solid-state ballasts demonstrated that fluorescent lamps could operate efficiently and flicker-free, setting the stage for modern solid-state lighting.

The scope of research under his leadership was exceptionally broad and attracted researchers from around the world. Berman’s group accelerated the development of new light sources by testing in the Laboratory’s photometric facilities; investigated surface-wave and electrodeless fluorescent lamps; and patented a revolutionary molecular emitter—the sulfur lamp. The LBNL Lighting Group conducted large-scale demonstrations of advanced lighting control systems in commercial buildings and supported the development of Radiance, a physically based ray-tracing system that accurately simulates lighting and visual appearance in architectural spaces.

In addition to his engineering work, Berman pushed the boundaries of vision science and human factors in lighting. His experiments on the spectral sensitivity of human vision—especially the role of scotopic, or dim-light, vision—reshaped the field’s understanding of brightness perception. He coined terminology still used in lighting research and provided the scientific basis for new standards that account for both light level and spectral content, work that ultimately helped shape national lighting standards. His more than 30 peer-reviewed papers remain widely cited in Lighting Research and Technology and the Journal of the Illuminating Engineering Society.

Berman’s contributions were recognized with numerous awards, including the U.S. Department of Energy’s Sadi Carnot Award for energy conservation (1988) and an honorary fellowship in the Illuminating Engineering Society (2010). He also received fellowships from the National Science Foundation, the Alfred P. Sloan Foundation, the Guggenheim Foundation (twice, in different disciplines), the Andrew Hamilton Foundation, and the Asian Foundation.

Berman remained active in research and consulting long after his retirement, continuing to publish into the 2010s on topics such as melanopic photometry and light’s influence on human physiology. His intellectual rigor, vision, and leadership left a deep mark on LBNL and the international lighting and building science communities, and his blend of physics, engineering, and human-centered research continues to inform modern lighting design.

He exemplified the Laboratory’s mission to bring science solutions to the world’s greatest challenges.