1) Binocular 2) Field glasses 3) Gear for a bird watcher 4) Opera glasses 5) Optical instrument 1) Field glasses 
Binoculars, field glasses or binocular telescopes are a pair of identical or mirror-symmetrical telescopes mounted side-by-side and aligned to point accurately in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. Most are sized to be held using both hands, although sizes vary widely from oper...
[Noun] Equipment to help you see far away objects.
A pair of low-power telescopes or prismatic spotting scopes mounted together parallel for stereoscopic (three-dimensional), magnified viewing of distant scenes. The opera glass employs Galilean telescopes and the field glass uses low-power nautical telescopes, but for greater magnifications, refle...
special lenses for seeing at a distance
field glasses noun an optical instrument designed for simultaneous use by both eyes
Optical instrument for viewing an object in magnification with both eyes; for example, field glasses and opera glasses. Binoculars consist of two telescopes containing lenses and prisms, which produce a stereoscopic effect as well as magnifying the image. Use of prisms has the effect of `fol...
an optical instrument for simultaneous use by both eyes