Far-Field Raman–Nath Diffraction of Polychromatic Light and a Ternary Data Transmission Scheme

Raman–Nath diffraction is produced by a thin acoustic beam. The standing sound wave acts as a thin phase grating, causing monochromatic light to interact with it and diffract into multiple orders. This phenomenon is typically used to redistribute light intensity at specific angles. The correspondence relationship applies to the spatial distribution of monochromatic light and transforms it into a spectral distribution of polychromatic light. This demonstrates that angular diffraction orders in the spatial domain correspond to wavelength orders in the spectral domain. Numerical results show that the amplitude of various spectral orders can be controlled by adjusting acoustic wave intensity. This property is proposed for use in achieving ternary digital data transmission.