Binoculars were a device used by Humans and other species. They had small identical mirrors inside them, which allowed a person to view distant objects with both eyes.
In 1986, a whale hunter stationed on a crow's nest aboard a Scandinavian whaling ship was using binoculars when he spotted George and Gracie. His captain had binoculars, which were supported by a wooden beam, and he used it to confirm the sighting. (Star Trek IV: The Voyage Home)
James T. Kirk and Spock used 23rd century versions of binoculars while on Nimbus III after landing far from Paradise City. Earlier, Leonard McCoy used the same binoculars to view Kirk climbing El Capitan. (Star Trek V: The Final Frontier)
Geordi La Forge's VISOR functioned much like binoculars in some cases. (TNG: "Hide and Q")
In 2375, Captain Jean-Luc Picard viewed the mountains on Ba'ku through binoculars with Anij while looking for suitable locations to hide from the Son'a. (Star Trek: Insurrection)