PEPPER: a photometer designed for the direct detection of extrasolar planets

PEPPER, a high-speed differential Polarization-Encoded Photometer and Polarimeter, is designed to perform self-calibrated shot noise-limited photometry from the ground to directly detect the light from the phase changes of close-in extrasolar planets. This is accomplished by using high-speed electro-optical switching techniques coupled with zero-read noise photon counting detectors to eliminate errors due to sky and detector gain drift variability. Here we present the design concept behind the photometer mode of PEPPER as well as some initial results from lab and on-sky engineering tests of the prototype instrument. The polarimeter mode of the instrument is presented in a seperate paper.