放映镜头 meaning in Chinese

projection lens

Resolving power test charts for projection lens
放映镜头解像能力测试标板
Method for determining various functions of projection lenses
放映镜头各种功能的测量方法
Brilliancy test charts for projection lenses
放映镜头用耀度测试标板
Slide projectors and slides ; projection lenses for overhead projectors , optical data
幻灯放映机和幻灯片.空架放映机用放映镜头.光学参数