examples of eyeglasses
The shape of glasses varies depending on the period and their use (e.g., correcting far- or nearsightedness, protecting the eye, magnifying).
opera glasses 
Optical magnifying instrument held in front of the eyes; it is used for looking at relatively close objects such as at the theater.
lorgnette 
Glasses held in front of the eyes by a handle attached to the side of one rim.
sunglasses 
Glasses with lenses that filter the sun’s glare to protect the eyes.
scissors-glasses 
Lorgnette whose lenses fold back over one another and can be slipped into the handle, which also acts as a case.
half-glasses 
Glasses with half lenses to correct farsightedness; the empty space above them is used to see distances.