Ring focus reflector design for topological charge multiplexing based on a perfect vortex beam

Abstract

A ring focus reflector is proposed for transmitting a perfect vortex (PV) beam, and the transmission characteristics of the PV beam with different topological charges in free space after passing through the reflector are studied. The reflector parameters can be determined by fitting the structural formula, and PV beams of different orders transmit with small spot sizes at the same time. The transmission trajectory calculated by the diffraction formula is consistent with the ray tracing results. The research results show that the reflector can achieve a high level of transmission efficiency of beams with different topological charges, which is conducive to the multiplexing of PV beams.

Cassegrain antenna using anomalously hollow beams with orbital angular momentum to improve transmission efficiency

“…In recent years, Cassegrain antenna with simple structure and easy manufacturing has been widely studied in Free-space optical communication [1][2][3][4], but the transmission efficiency is reduced due to the energy loss caused by the reflection of secondary reflector of Cassegrain antenna [5,6]. In order to improve the transmission efficiency of antenna, some researchers have designed off-axis antennas [7], while others have chosen to optimize the primary and secondary mirrors [8][9][10]. But they also have the disadvantage of complex surface processing.…”