Development Of Visible Light Reliable High Frequency Pulse Target Generator

With development of high-speed missile imaging detection aero-optical effects, certain accomplishments on theoretical analysis have been obtained. The laboratory test system needs to be built to vertify the correctness and validity of theory. At the same time, to study the transient influence of high-speed flow on image transmission, an aero-optical effect experiment of wind tunnel is needed furtherly on the foundation of the transform of wind tunnel, in order to use the researching accomplishment of aero-optical effects in the aero-optical distortion image adjustment evaluation. In above-mentioned experiment, to study the influence of aero-optical effects on the optical image transmission at different exposure time, and getting the firsthand experiment data of high-speed flow influence on image transmission, transmission images of point targets at different exposure time and of surface targets at steady-state are required. So a generator of visible light steady-state surface targets and pulse point targets is developed, which offers targets for studying transient optical transmission effects of flow in high-speed wind tunnel.This generator is composed of three light sources, two sets of optical system and one control circuit, including a YAG laser of pulse width of 10ns and frequency of 1 kHz. Semiconductor laser outputs laser beams of pulse width from 1μs to continuous frequency of 1 kHz through control circuit. The working wave band of steady-state collimated surface targets is 0.45~0.65μm, and projection angle is adjustable between 0.3°~3°through changing field of view diaphragm. The core of this system is AT89C52 MCU. In this system, CPLD controls semiconductor laser, the FET controls surface light source by the way of changing input voltage to control current, and the pulse signal of 1kHz produced by AT89C2051MCU controls YAG laser. The graphics lattice liquid crystal module MGLS-240128T is used to display information, and the interface is friendly. The synchronous signal of MC1311 CMOS camera is shaped by monostable trigger 74LS221. The data are stored in AT24C02, protected in the case of electricity loss.Experiments show that this system is of reliable performance, compact structure, and convenient use. This system also completely satisfies all the requirements of laboratory.