an optical instrument for viewing objects that are above the level of direct sight or in an otherwise obstructed field of vision, consisting essentially of a tube with an arrangement of prisms or mirrors and, usually, lenses: used especially in submarines.
They interpret the world through their own, somewhat limited, periscope.
No doubt, from an underground bunker with a periscope.
The van is equipped with a video camera and a periscope.
The periscope is mounted in a corner of a furnace to allow viewing of the entire field of the combustion space.
The system must include the ability to operate a wireless periscope system.
Camera focus via periscope eyepiece and real-time computer-displayed video.
The sophisticated vessel also has a conning tower, periscope and air conditioning system.
British Dictionary definitions for periscope
any of a number of optical instruments that enable the user to view objects that are not in the direct line of vision, such as one in a submarine for looking above the surface of the water. They have a system of mirrors or prisms to reflect the light and often contain focusing lenses
C19: from Greek periskopein to look around; see peri-, -scope