You can get glass lenses at specialized optical shops and some high-end eyewear retailers that offer premium options. Many optometrists and ophthalmologists also provide glass lens options during eye exams and fittings. Additionally, online eyewear retailers may offer glass lenses as a customization option for certain frames. Always check with the provider to ensure they have the desired lens material available.
Not all... Some spectacle-makers use plastic lenses instead of glass.
The may be made of glass or plastic, but in either case they ARE always actual lenses.
Lenses are typically made of glass or transparent plastic
The raw material of lenses is plastic polymer in most cases. There are some lenses which are made from glass materials as well.
contact lenses!
The advantage of plastic is that it is lightweight and more impact resistant than glass. The advantage of glass is that it is scratch resistant and provides the clearest possible vision.
They were first made of glass, but now they are made of plastic.
Typically glass or plastic. If you are interested in learning specifically about contact lenses, you should visit Guru4Eyes.com (www.Guru4Eyes.com/contactlenses.html)
glass can be very fragile
The lenses are made from either glass or plastic. The frames are generally made from plastic, nylon, a metal or metal alloy.
Optical lenses are commonly made from glass, plastic (polycarbonate or acrylic), or specialty materials like CR-39. Each material has different properties that affect the lens performance, weight, and durability.
galileo used glass with a layer of plastic.