FIRST, a high dynamic range imager, mounted on the Shane telescope at Lick Observatory. E. Huby, Obs. Paris FIRST (Fibered Imager foR a Single Telescope) is an innovative instrument dedicated to high dynamic range imaging and high angular resolution, that are both requirements to detect exoplanets. Simulations predict a dynamic range up to 10^6 close to the diffraction limit lambda/D, or, in other words, at a few tens of milliarcseconds using FIRST with an 8-m telescope at 600 nm. Its principle relies on both techniques of aperture masking and single-mode spatial filtering. A prototype of FIRST has been set up on the 3-m Shane telescope at Lick Observatory in July 2010 for the successful first light of the instrument. Since then, the prototype has evolved into an 18-fiber combiner, with closure phases measured with accuracy better than one degree. The current performances should allow to detect companions with dynamic range on the order of 100, up to 300 in less than one hour observation time for the brightest targets. We hope to achieve dynamic range beyond 10^3 in a near future by improving the stability and thus the accuracy of the measurements, and by increasing the number of sub-pupils.