弯月形透镜

meniscus lens

to bend / bent / a bend / a turn (in the road etc) / CL:道[dao4]

to bend / bent / a bend; a turn (in a road etc) / CL:道[dao4]

moon / month / monthly / CL:個|个[ge4],輪|轮[lun2]

to appear / to look / form / shape

to penetrate / to pass through / thoroughly / completely / transparent / to appear / to show

(bound form) to penetrate; to seep through / to tell secretly; to leak / thoroughly; through and through / to appear; to show

lens (optics)

mirror / lens