QUBIC is an experiment dedicated to the measurement of the B-mode polarization from the Cosmic Microwave Background (CMB), using a novel technology: Bolometric Interferometry. The instrument will have 2 focal planes at 150 GHz and 220 GHz. Thanks to its unique spectroimaging capabilities, QUBIC will also be a powerful instrument to constrain foreground contamination (thermal galaxy dust emission, synchrotron emission, ...). The technical demonstrator has been tested and the concept of this new instrument has been validated. In this talk, I will 1rst explain the instrument architecture, focussing on the optical design. Some of the calibration results will be presented, showing that we actually have a working bolometric interferometer. The unique design of QUBIC brings new possibilities to CMB polarization mapping