设计了一款适于医疗培训用投影式头盔物镜系统,出瞳直径8mm,视场50°,能够满足对角0.9英寸微显示器对超高分辨SXGA模式的显示要求.其结构紧凑,口径10mm,长度12mm,重量仅有5g.本物镜系统场曲仅0.35D,畸变仅0.64%.为考察本投影式头盔系统的成像特性,研究了不同“逆反射材料”的特性.实验得到高强级逆反射材料在±40°视场范围内反射光强无明显变化,适合做为投影屏幕材料.定量分析了逆反射屏放置位置对成像的影响.
A head-mounted projective display lens with a View field of 50° for medical application is designed. The exit pupil diameter of the system is 8 mm, while the maximum diameter of the lens is 10 mm. The total length of the designed system is 10 mm and the weight is only 5g. The maximum distortion of the system is less than 0. 64% and the maximum field curvature is 0. 35 D. The lens can satisfy the requirement of a 0. 9 inch miniature display with a display model of SXGA. To know the imaging performance of the HMPDs, different retro-reflective materials are investigated. It is shown in the experiments that the image intensity of the High Intensity Grade Reflective Sheeting is fairly constant for a tinted angle in a range of ±40°. Therefore it can be used as retro reflective screen. The influences of retro- reflective material's position on the imaging quality are also investigated.