Microscopes; Eyepieces; Objectives (lenses) (optics); Mirrors for inspecting work; Optical lenses; Magnifying glasses (optics); Periscopes; Mirrors (optics); Optical glass; Refractors; Binoculars; Telescopes; Sighting telescopes for firearms; Optical condensers; Telescopic sights for artillery; Surveying instruments; Television cameras; Marine compasses; Telemeters; Measures