Neutron imaging is widely used in scientific experiments and industrial applications. The neutron sensitive microchannel plate (nMCP) detector plays the role of registering penetrating neutrons and realizing high spatial resolution. The delay-line readout anode can achieve a high spatial resolution with an acceptable throughput. To optimize working parameters of the nMCP detector with the delay-line readout anode, simulations are conducted to understand the signal formation process. In order to realize the best temporal resolution (and hence the best spatial resolution), the differential current output by the delay line anode is calculated to find the largest slope of the rising edge of the current.