Optical design of visual simulation lens for dynamic target simulator

A kind of visual simulation lens for dynamic optical target simulator based on liquid crystal light valve was studied and designed. The dynamic optical target simulator was composed of LCD display system, visual simulation lens, external projector, computer, cable, and adjustable mechanism. According to the instruction from the testing equipment, the simulated image of earth was generated and the liquid crystal light valve was controlled to display the simulated image of earth by computer. The liquid crystal light valve was situated on the focal plane of the visual simulation lens. Light coming from the dynamic optical target simulator was parallel light, and infinite analogue observation effect could be generated in a finite distance. The optical sensor gathered the light coming from the visual simulation lens and finished imaging simulation. Inversed telephoto structure of secondary imagery method was adopted by visual simulation lens, and in order to match the emergent light of liquid crystal light valve, telecentric beam path structure was also adopted. The focal length of the visual simulation lens was -22.447 mm, the field angle was 45,and the effective field of view was 301.5301.5. The barrel distortion of the visual simulation lens was smaller than 1%, the modulation transfer function (MTF) was greater than 0.45 at Nyquist frequency, and the length of the visual simulation lens was 325 mm. Illumination uniformity of optical sensors was better than 95.4% under the coordination between the visual simulation lens and the optical sensor. Finally the test results of the visual simulation lens were listed.