Fabrication and characterization of two-dimensional optical low pass filter

Two-dimensional optical low pass filter (OLPF) was designed, fabricated and tested in our lab. The modulation transfer function (MTF) of OLPF shows that cut-off frequency is 96.151p/mm in x and y direction, which is satisfied with our design. The transmissions in the visible and infrared regions of the spectrum are mostly above 95% and less than 2%, respectively. The error of every plate thickness is tested less than 0.34% by the experiment of pulse response. The spatial frequency test results show that our device has good low filter performance, matches with the solid state image sensor and well restrains the moire effect and false colors distortion.