  The limits to the angular resolution achievable with conventional
ground-based telescopes are unchanged over 70 years. Atmospheric turbulence
limits image quality to typically ~1 arcsec in practice. We have developed a
new concept of ground-based imaging instrument called GravityCam capable of
delivering significantly sharper images from the ground than is normally
possible without adaptive optics. The acquisition of visible images at high
speed without significant noise penalty has been made possible by advances in
optical and near IR imaging technologies. Images are recorded at high speed and
then aligned before combination and can yield a 3-5 fold improvement in image
resolution. Very wide survey fields are possible with widefield telescope
optics. We describe GravityCam and detail its application to accelerate greatly
the rate of detection of Earth size planets by gravitational microlensing.
GravityCam will also improve substantially the quality of weak shear studies of
dark matter distribution in distant clusters of galaxies. The microlensing
survey will also provide a vast dataset for asteroseismology studies. In
addition, GravityCam promises to generate a unique data set that will help us
understand of the population of the Kuiper belt and possibly the Oort cloud.
