Reducing the bending radius of low-index-contrast waveguides is essential in reducing the size of the integrated optical components. A polymeric multimode waveguide bend is presented based on the Eaton lens. Ray-tracing calculations are utilized to truncate the Eaton lens in order to improve the performance of the bend. The truncation of the lens decreases the footprint of the bend as well. A designed waveguide bend with a radius of 18.4μm is implemented by a concentric cylindrical multilayer structure. Average bend losses of 0.69 and 0.87dB are achieved for the TM0 and TM1 modes, respectively, in the C-band of optical communication. The bend loss is lower than 1dB in a bandwidth of 1520-1675nm for both modes.