Research on streak tube imaging lidar based on photocathode range gating method

In this paper, a streak tube laser lidar(STIL) based on cathode gating (CG) method is introduced,range gating of laser echo is realized by triggering the photocathode voltage of the streak tube. A Nd:YAG pulse laser is used as the light source, with a wavelength of 532 nm and a maximum repetition rate of 10 Hz,the raw image was collected by CCD with a resolution of 640×480. Imaging experiments of a target with a stand-off distance of 2 km are carried out by using the developed STIL system, the intensifier gating (IG) method and the CG method were used respectively. The experimental results show that, compared with IG mode, the CG mode with the same parameters has the advantages of strong detection ability and high signal-to-noise ratio(SNR). It is proved that CG mode is more suitable for the range gating of the STIL, and the SNR of the raw image is raised from 4.2 dB in non-gating mode to 16.8 dB in CG mode which effectively improves the image definition.