Design Of Visual Display System Based On Freeform Surface

Visual display system is paramount to flight simulation, considering the technical requirements of virtual distance for some flight training, an approach of achieving continuous change of visual distance is proposed by using freeform surfaces as projection screen. Each point on the freeform surface corresponds to each object point with a certain object distance. The massive image points can be got by macro program of ZEMAX optical design software, and the freeform surface can be got by reverse engineering. This freeform projection screen can meet the demands of continuous change of visual distance.Based on the macro program and reverse engineering, the visual display system with continuous change of visual distance was developed with the technical specifications: horizontal field of view180°, vertical field of view65°(20°～45°), visual distance from7m to infinity. This system has achieved continuous change of visual distance, strong space feeling of depth, and is more suitable for flying and landing training of pilots. The resolution of the system is better than1.5’ at all of the field.