Abstract: Large telescopes have to be short and therefore optically fast. This makes it difficult to achieve wide fields. The subject's history is briefly reviewed including projects yet to be completed. The best combination of wide (> 4 degree) field and short telescope achieved as yet is Willstrop's three mirror telescope. The analytic theory of all three-mirror aplanatic telescopes is then developed and the problem solved for the special case of a parabolic primary. Exploration of the problem for a primary of any given shape is still in progress.

Brief Biography of the Speaker:
Donald Lynden-Bell is Emeritus Professor of Astrophysics at the University of Cambridge where he held his chair 1972-2001. He was director of the University's Institute of Astronomy 1972-77,1982-87,1992-94. After taking his MA and PhD in Cambridge(1960)he was a postdoc at Caltech and the Mt Wilson and Palomar Observatories where he worked with Eggen and Sandage on Evidence as to how the Galaxy formed. He returned to the Mathematics department DAMTP in Cambridge and to his fellowship at Clare College but then left for 7 years of astronomy at the Royal Greenwich Observatory at Herstmonceux Castle in Sussex. There in 1969 he produced his theory that Quasars were giant black holes in the Nuclei of Galaxies accreting matter. For this work he was awarded in 2008 the first Kavli prize in Astrophysics jointly with Maarten Schmidt who discovered Quasars.
He is a fellow of the Royal Society, A foreign member of the US National Academy of Sciences, a past president and gold medallist of the Royal Astronomical Society, A foreign member of the AAS and a Bruce Medallist of the Astronomical Society of the Pacific. Interests include: Relativity, Dynamics, Statistical Mechanics, MHD. Galaxies. His first paper on optics was in 2002.