Axial cosinoidal structured illumination that the intensity along the axis presents a cosinoidal distribution plays important role in many fields, such as optical tweezers, optical micromanipulation and optical modulation. However, the generation of axial cosinoidal structured illumination with controllable phase and period is a challenge. Here, we propose a novel method for generating axial cosinoidal structured illumination by using phase-only spatial light modulator. We implemented axial cosinoidal structured illumination using holographic technique. The computer generates two concentric circular slits with different radius, a prism phase is applied on the slits to tilts the beam that incidents on the slits away from the optical axis. Different annular beam produce Bessel beams with different axial wave vectors, axial cosinoidal structured illumination can be obtained from the interference between two Bessel beams. We theoretically and experimentally verify that the method can effectively generate axial cosinoidal structured illumination.
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