A University of Rochester professor who is an expert on the behavior and physics of light -- a subject with applications ranging from data encryption to lasers to the age of the universe -- will be awarded two honorary degrees this spring.

Emil Wolf, Wilson Professor of Optical Physics and Professor of Optics, will receive honorary doctor of science degrees from the University of Bristol in England and the University of Laval in Quebec. Bristol is a widely recognized center of study for physics and mathematics, and Quebec is known worldwide for its optics research, both at Laval and at the Canadian National Institute of Optics.

The honorary doctorates are being awarded for Wolf's lifetime of work in electromagnetic theory, physical optics, and the phenomenon of partial coherence, which describes the behavior of light created by atoms that aren't fully in sync with each other. This includes everything in the realm between ordinary light (like that from a light bulb or a flame), which comes from atoms that emit photons randomly, and light created by atoms in perfect step with one another, such as that from a laser.

Wolf has made a series of discoveries showing the importance of how this mix of order and disorder affects the universe and how it can be manipulated for a variety of applications. He is credited with opening up a new field of medical imaging, known as diffraction tomography, which is being used to develop the next generation of clinical imaging devices. Physicians are using Wolf's theories to develop new laser-based technologies to see inside the human body with greater resolution and to improve the resolution of ultrasound scans of the internal organs. Wolf's theories were further developed by his former student, Anthony Devaney, and are now used by another Rochester graduate, Alan Witten, to find long-buried dinosaurs, utility lines, and other large objects.

Ten years ago Wolf discovered that partial coherence can affect the way light travels through the universe, a finding that surprised physicists and could have implications for our knowledge about the size and age of the universe. In addition, Wolf and his students have used the statistical information long hidden in light and radio waves to develop a new technique that would allow astronomers to make some measurements of stars much faster and with less equipment than they use now. The theory has been verified in laboratory experiments.

The latest application of Wolf's work may be in cryptography. His work allows scientists to control certain properties of light in a way no one has considered before by developing devices that transmit some light while filtering out some other types of light. Such filters could be used to encrypt light signals carrying information in computers, phone lines, or fibers.

Wolf's papers are full of advanced mathematics, which he regards as "the natural language of physics." He has loved mathematics since he was a schoolboy growing up in Prague. In fact, he joined the Czech Mathematical Society more than half a century ago.

"It is remarkable that something as abstract as mathematics can relate to the world so directly," says Wolf. "Good mathematics is like poetry. The natural world, like music, can be very beautiful and can appeal deeply to our senses."

Wolf is particularly well known for the book, Principles of Optics, which he wrote with Nobel laureate Max Born; the book is now in its sixth edition. As they compiled the book, Born became somewhat upset with Wolf for delaying publication because Wolf insisted on adding a chapter on partial coherence theory. Shortly after the book was published in 1959, the laser was invented, and that chapter provided the only thorough explanation at the time of some of the wave properties of laser light. Born quickly became enamored, not frustrated, with the extra chapter. Seventy years ago Born himself also received an honorary degree from Bristol University.

Since he joined the University of Rochester faculty in 1959, Wolf and his colleagues have organized seven well known international Rochester Conferences on Coherence and Quantum Optics. He is the editor of Progress in Optics, an ongoing series of 36 volumes keeping pace with the field's developments. Two years ago he and a colleague, Professor Leonard Mandel, published Optical Coherence and Quantum Optics, a book that has been widely acclaimed as a masterful treatment of the nature of light.

Wolf has received many honors, including the Frederick Ives Medal and the Max Born Medal from the Optical Society of America (OSA), the Michelson Medal of the Franklin Institute, and the Marconi Medal of the Italian National Research Council. He is an honorary member and past president of OSA and an honorary member of the optical societies of India and Australia. He received his bachelor's and doctoral degrees from Bristol and a doctor of science degree from the University of Edinburgh.

Wolf's research has been continuously funded by at least one of several agencies since he arrived in Rochester in 1959. His current funding comes from the Department of Energy, the Air Force, the Army, the National Science Foundation, New York State, and several local companies through the University's NSF Center for Electronic Imaging Systems.

The recent awards bring to five the number of honorary degrees Wolf has received in recent years. He has also received degrees from universities in Scotland, the Netherlands, and the Czech Republic.