Giuliano Toraldo di Francia

In Memoriam: Giuliano Toraldo di Francia

April 26, 2011

OSA Mourns the Loss of Giuliano Toraldo di Francia, 1916-2011


Giuliano Toraldo di Francia, an OSA Fellow and a Professor Emeritus at the University of Florence, Italy, died on 26 April 2011.  He was 94.  Toraldo di Francia’s death was announced by former city councilor and Minister Valdo Spini of Florence, in a statement that expressed deep sorrow and mourning for the loss of a great scientist who was also “steeped in humanistic culture.”

Toraldo di Francia introduced the concept of superresolution and degrees of freedom of images.  Toraldo filters are named for him, stemming from his investigation of pupil-plane filtering as a way to increase the resolution of an imaging system beyond the diffraction limit by using a set of concentric amplitude and/or phase filters at the pupil of an image-forming system.  He was known for his work in the formulation of the inverse interference principle and experimental demonstration of the existence of evanescent waves (leaky waves).  His most recent contributions concerned the dissemination of the philosophy of science, and the relationship between science and society and between scientific and humanistic culture.

Giuliano Toraldo di Francia was born in Florence in 1916, the year that OSA was incorporated.  In 1949, he joined the Faculty of Mathematical, Physical and Natural Sciences at the University of Florence. He taught optics at the University of Rochester for two years and was then hired as a professor at the National Institute of Optics, where he remained until 1958, when he was appointed professor of optics at the University of Florence.  He became Institute chair in 1963.  He retired in 1991 and was named professor emeritus at that time. Toraldo di Francia also served as director of IROE, the Institute of Research on Electromagnetic Waves of CNR (now the Institute of Applied Physics “Nello Carrara,” IFAC-CNR).

He was President of the Italian Society of Physics (1968-1973) and of the International Commission for Optics (ICO) (1966-1969).  He was also president of the Italian Society of Logic and Philosophy of Science, the Forum for the Problems of Peace and War, and the School of Music in Fiesole.

A prolific author, Toraldo di Francia became known to the international academic world for the books “Onde Elettromagnetiche” (1953), and "The Diffraction of Light" (1958).  He also wrote extensively on the philosophy of science.  “The Investigation of the Physical World,” originally published in Italian in 1976, is both a high-level popularization and a critical appraisal of the methods scientists use to investigate the physical world.

A long-time OSA member, Toraldo di Francia was named an OSA Fellow in 1965.  In 1969, he was awarded the Institute of Physics’ Young Medal, and he received the OSA C.E.K Mees Medal in 1971.

Toraldo di Francia served in the Resistance movement during World War II.  He was an active member in the Fratelli Rosselli of Florence, a political culture organization.  A passionate Dante scholar, he was interested in music, art and philosophy. He played tennis until age 90 and he loved swimming and taking long walks in the mountains. 

Giuliano Toraldo di Francia is survived by his wife, Professor Maria Luisa Dalla Chiara, a son, Cristiano, and two daughters, Monica and Isabella.

A memorial service will be held at the University of Florence on 30 April 2011. 

If you would like to make a donation to the OSA Foundation in memory of Prof. Toraldo di Francia, please visit