Based on the microprocessor and combined with analog delay circuit and digital logic circuit, a strobe pulse source with a resolution of 5 ns, a minimum pulse width of 65 ns, a frequency up to 1 MHz, and remote control by the host computer is designed. Using this pulse source in combination with a gate power supply, the gated shutter time of the ICCD coated with a metallic conductive substrate and no metallic conductive substrate on the cathode are tested. The results show that the ICCD has a shorter turn-on time when metal substrates are plated. The corresponding equivalent circuit model and the RC equivalent equation which the opening and closing process of photocathode met are established, qualitative analysis shows that the decrease in the cathode surface resistance is the main factor to shorten the ICCD open time.