A system for imaging tissue includes a millimeter wave Quasi-optical backward wave oscillator. The invention thus relates to the plants, seeds and tissue cultures of the variety I028727, and to methods for producing a corn plant produced by crossing a corn plant of variety I028727 with itself or with another corn plant, such as a plant of another variety. The central cylinder has an aperture provided in a side surface thereof. Each fiber of the first group begins in the neck wall at one end of the balloon, extends continuously in the longitudinal direction and terminates in the neck wall at the opposite end of the balloon. The at least one first electrode is arranged in an intermediate portion with respect to the interface such that the intermediate portion of the interface is moved substantially in direction of the optical axis in dependence on the voltage applied between the at least one first electrode and the at least one second electrode.