Wide-angle infinity display equipment (WIDE) is an important part of airplane simulator which directly affects the performance of airplane simulator. Surface shape of collimating mirror and back-projection screen in WIDE is a key factor which decides imaging quality. Therefore, the design of collimating mirror and back-projection screen turns into a key problem in WIDE development. Aiming at the technical requirement of WIDE of airplane simulator for two-seater airplanes, the condition of compensating astigmation of zero field of view was discussed, the surface of collimating mirror was designed to be bracelet form to ensure the astigmation of zero field of view would be zero, and determine the size of collimating mirror. On the principle for minimum disc of confusion, shape and location of back-projection screen was obtained by inverse ray tracing, finally the collimation precision calculated. The WIDE designed could provide 180 horizontal field angle and 45 vertical field angle, and is already used in flight training.