In Memoriam: Hendrik de Lang, 1920-2010

Hendrik DeLangHendrik de Lang, an OSA Fellow Emeritus and a member of the Society since 1962, died on 7 October 2010, three days after suffering a mild heart attack, in a hospital in Eindhoven, The Netherlands. He was 90 years old.

Hendrik de Lang was born in 1920 in Groningen, The Netherlands, and studied physics at Groningen University. Before he received his physics degree, his studies were interrupted by the Second World War. Forced by the occupying forces to work for them in Berlin, Germany, de Lang and his friend, Roel Flik, decided to flee back to The Netherlands, where de Lang had to stay in hiding until the end of the war. During this period he met his future wife, Sientje Danes, while ice skating in the open air.

After finishing his studies at the Groningen University, de Lang continued his activities there, working in Frits Zernike's group. In 1955, he joined the Philips Research Laboratories in Eindhoven, The Netherlands. His research interests were in optical design and coherent optics. In 1962, he became the group leader of the optics group at Philips and he conducted early research on the polarization properties of helium-neon lasers. Among his many accomplishments was the Plumbicon color-separating prism system (with G. Bouwhuis, 1965).

In 1966, de Lang obtained his PhD degree (cum laude) from Utrecht University. In the later years of his life, he was proud that in his dissertation he was the first to propose how ring lasers might be used as a gyroscope.

De Lang took over the vacant optics chair at Delft University in 1967, but this position didn't suit him very well. In 1969, he returned to Philips to become the group leader of the electron optics group. He retired from Philips in 1980.

Prior to his death, de Lang had nearly completed an article to defend the theory of light as proposed in "Traité de la lumière" by his hero, the Dutch scientist Christiaan Huygens. The article will be published posthumously.

Throughout his life, de Lang was devoted to classical music. He not only played the violin and viola, but he also built some fine instruments.

De Lang was cremated and his ashes scattered in the province of Groningen in the northern part of The Netherlands. He leaves behind his wife, three children and four grandchildren.

This obituary was contributed by Eltjo de Lang, son of Hendrik de Lang.

If you would like to make a donation to the OSA Foundation in memory of Hendrik de Lang, please visit www.osa-foundation.org/give.