资料来源 : Webster's Revised Unabridged Dictionary (1913)

Optigraph \Op"ti*graph\, n. [Optic + -graph: cf. F.
   opticographe. See {Optic}, a. ]
   A telescope with a diagonal eyepiece, suspended vertically in
   gimbals by the object end beneath a fixed diagonal plane
   mirror. It is used for delineating landscapes, by means of a
   pencil at the eye end which leaves the delineation on paper.