Thoretical And Experimental Research On Gain Modulating Scannerless Imaging Ladar

Scannerless imaging ladar is one of developing trends of ladar. We propose a gain modulating scannerless imaging ladar system, using method of gain modulating, by two imaging processes, eliminate intensity information, reserve range information, and thus format the range image. This system is a new program of scannerless imaging ladar. Without constraints from scanning process, it will improve speed of imaging ladar.This paper conducts a feasibility test program experiment. As ICCD device costs high, based on analysis of existing photoelectric detector, we choose photomultiplier tube as a substitute for the principle verification experiment. Results show that the PMT working with 100kHz modulating voltage which is monotonically increasing, followed by monotonically increasing output gains, the relationship between the two is about two times every 100 volts; Thus we have proved that the gain modulating scannerless ladar imaging system is feasible.As the main technical difficulties of ICCD gain modulating system are solved, we build the gain modulating scannerless imaging experimental system. Using this system, we conduct a progressive mode imaging experiments. The first experiment is on the indoor targets in series, 35m to 45m away, and spacing at 2m. After the data processing, we acquire range image of the targets, with clear levels and sharp edge. We also choose the target 30m height from ground, with horizontal distance of 30 m to 70 m. We acquire range Image of this target after the data processing. The details of target in the range image can be identified by naked eyes.Experimental results show that the gain modulating ladar imaging system are in good working order with target in range of 100m and with range resolution of 2m.