This reminds me of how weird I found the word "glass" when I first learned it in English, as in my language we have: 1) a word for the substance (we call the glass bottles the same, though); 2) a word for the glass of the window 3) a word for the drinking recipient; 4) yet another one for the magnifying thingies.
Binoculars is Fernglas / Opernglas / Feldstecher,
but there is a small option that someone says to his friend who sits next to him in the stadium:
"Kannst du mir bitte mal dein Glas geben?", But you would normally hear "Fernglas/Opernglas". One would only say "Glas" on its own, when it cannot be confused with the normal meaning (drinking glass). If the friend would have a glass of wine and binoculars, and you ask him for the "Glas" that may cause confusion.
Bottom line, better to use Fernglas/Opernglas for binoculars, but: "Gib mir mal dein Glas" for binocular is possible.