With the development of image recognition technology, the demand for face recognition systems with an iris recognition filter is constantly increasing. With large incident angles, recognition failure often occurs owing to a large spectral offset; therefore, a bandpass filter with good low-angle effect is required. Herein, a bandpass filter with large angle and small spectral offset is designed based on the spectral splitting principle. By adjusting the hydrogen gas flow, the refraction index of Si-H is improved while maintaining the low absorption, enhancing the angle effect of the iris recognition filter. Based on available literature on the deposition of thin films, the problem of film removal due to its loose internal structure is solved herein by adopting a special film system structure; testing results show that this structure meets the technical requirements of iris recognition filters.