- Abstract In Optical Coherence Tomography (OCT), both high axial and lateral resolutions are desired. While axial (z-axis) resolution is achieved by a broadband source, lateral (x–y axes) resolution is achieved by high NA lenses. However, high NA objectives result in decreased depth of focus (DOF). The small DOF makes it difficult to obtain single shot imaging of biological samples having large lateral dimension. In this work we incorporate special interfering phase mask allowing to extend the DOF of an OCT system and to allow imaging of samples without axial scanning.