Phase-shifted Fresnel axicon.
We propose an optical element: a phase-shifted Fresnel axicon for generation of multiple Bessel beams. By giving a binary phase modulation to the standard Fresnel axicon, the proposed element is generated. The phase profile of the binary phase modulation is engineered to generate two and three Bessel beams of equal intensities. This composite optical element is fabricated using electron beam direct writing. The performance of the fabricated device is evaluated using a semiconductor laser, and the generation of two and three Bessel beams is successfully demonstrated.
Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
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Vijayakumar
Shanti
S
Bhattacharya