To theoretically describe, design and test an open head birdcage coil, called opencage, that facilitates access to the patient under examination. This access improves the patient's comfort, but also may be suitable for many tasks, for example fMRI or motion correction. Theory and Methods: Using transfer matrix approach, the birdcagelike coil having non-periodical distribution of rungs is constructed with optimized currents in the coil's rungs. Subsequently, the the coil was adjusted in full-wave simulations. Eventually, these results were confirmed on phantom and in-vivo imaging. Results: Indeed, the high enough computed isolation coefficient between the feeding ports of the coil as well as a birdcage-like B + 1 pattern showed that the coil was properly optimized. After the numerical optimization, the coil was assembled and fine tuned and matched on the bench. Experimental assessment of the developed coil showed slightly lower B + 1 homogeneity, competitive transmit efficiency and coverage to the birdcage coil of comparable size. Conclusion: It was shown that the proposed open birdcage coil can be designed without dramatic drop of performance by means of B1 field homogeneity and efficiency, SAR.