Effect of MTF on depth resolution in imaging three-dimensional ladar system

We present a profile of imaging three-dimensional ladar (I3DL), where the range information is obtained by time of flight method from two different gains intensified two-dimensional (2D) images. The effect of optical transfer function on range resolution was studied in range images captured by I3DL. The edge response method was used to calculate modulation transfer function (MTF) and the line spread function (LSF) of the I3DL system in an outdoor test. The range resolution degradation by MTF limit was proved by experiment results. It was found that the method of pixels binning became an acceptable approach to improve the range solution without reducing the spatial resolution in range images, given the MTF of present system relative low, due to the larger pixel of CCD cameras.