Mode selection of laser radiation by computer-generated optical elements

Abstract New holographical optical elements—modans—are described that are computer-generated and aimed to select modes of laser radiation. Modans are matched with modal spatial configurations and are able to transform the modal-power distribution into the focal-intensity distribution. It is shown that optical systems containing modans are able to measure modal power and phase distribution at the fiber or laser output. Theoretical and experimental results confirm the possibilities of forming coherent beams with required modal compositions by diffractive optical elements. Applications of modans are investigated for fiber-optical sensors of microshifts.