This report describes the inception, development and extensive use over 30 years of elliptical polarimeters at the Uni\-versity of Pennsylvania. The initial Mark I polarimeter design utilized oriented retarder plates and a calcite Foster-Clarke prism as the analyzer. The Mark I polarimeter was used on the Kitt Peak 0.9 m in 1969-70 to accomplish a survey of ap\-proximately 70 objects before the device was relocated to the 0.72 m reflector at the Flower and Cook Observatory. Suc\-cessive generations of automation and improvements included the early-80’s optical redesign to utilize a photoelastic modulated wave plate and an Ithaco lock-in amplifier–the photoelastic modulating polarimeter. The final design in 2000 concluded with a fully remote operable device. The legacy of the polarimetric programs includes studies of close binaries, pulsating hot stars, and luminous late-type variables.

• Koch, Robert H.(Department of Physics and Astronomy, University of Pennsylvania)
• Wolf, George W.( Missouri State University) | Wolf, George W.
• Hull, Anthony B.( University of New Mexico, Albuquerque) | Hull, Anthony B.
• Elias, Nicholas M. II( National Radio Astronomy Observatory) | Elias, Nicholas M. II
• Holenstein, Bruce D.( Gravic, Inc.) | Holenstein, Bruce D.
• Mitchell, Richard J.( Gravic, Inc.) | Mitchell, Richard J.