基于微环构成的滤波器，因其具有较大曲率半径以及窄带宽等缺陷，提出一种马赫-曾德尔结构结合矩形环谐振腔的高效紧凑光滤波器。器件结构均由基于受抑全内反射原理的沟槽型微纳光子耦合器和基于全内反射原理的90°弯曲波导构成。采用状态空间表示法和时域有限差分法对器件的品质因数、传输特性等参数进行了计算和仿真。状态空间表示法对比了不同耦合系数及损耗系数对滤波特性的影响；利用时域有限差分法仿真得到在反射系数接近穿透系数时，呈现出的通带和阻带带宽不等的非对称波长交错滤波效果，在反射系数远大于穿透系数时，滤波器品质因子约为3120，并获得在25 μm × 8 μm 面积下自由光谱范围高达50.6 nm 的特性。该器件提高了在单片光子集成回路中的集成度且具备二维方向布局配置及扩展的能力。

Optical filter based on microring resonator usually has drawbacks such as narrow bandwidth and larger radius of curvature. An ultra-compact optical filter consisting of rectangular ring resonator incorporated with two Mach-Zehnder interferometers is proposed and optimized, and the device is formed by trench-based nanophotonic frustrated total internal reflection couplers and total internal reflection mirror-based 90o bends waveguide. The performances such as transfer function, quality factor, and transmission characteristic are analyzed by using statespace representation and finite difference time domain (FDTD) methods. The dependence of filtering features on both different coupling coefficients and loss coefficients is calculated with state-space representation method. The FDTD simulation results show the device exhibits an asymmetric wavelength interleaver filtering effect with the different ratios of pass-band and stop-band bandwidths when the coupler reflection coefficient is close to the coupler transmission coefficient. The quality factor of about 3120 and the free spectral range up to 50.6 nm are observed in such small 25 μm ×8 μm chip area when the coupler reflection coefficient is far larger than the coupler transmission coefficient. The compact configuration of device layout is beneficial to the extension at two-dimensional directions for highly dense photonic integrated circuits.