1 x 9 MMI splitter prepared by 3D lithography and characterized by NSOM

We proposed, simulated and fabricated a new type of three-dimensional (3D) optical splitter based on multimode interference (MMI). Splitter was designed for the wavelength of 1550 nm and the input signal is divided into 9 outputs. The multimode waveguide part of the splitter was designed as a block with square basis of cross-section of 26 x 26 μm2 and length of 211 μm. We used the IP-Dip polymer as a standard material for 3D laser lithography. We present the design, simulated and measured optical field distribution in the output of the MMI splitter and its direct integration on the single mode optical fiber.