It is called the lens.
These type of glasses are called bifocals.
Binoculars, glasses, magnifying glasses and teliscopes
Glasses/ spectacles. They sit on the bridge of your nose and you can see through them.
glasses
price
Yes, if you can see better through glasses other than with normal vision this often means you need glasses yourself.
They are planos glasses I think, you can see it when you look through them.
x-ray glasses
X-ray glasses do not work. That's science fiction. There are no X-ray glasses you can wear and see through things.
special sun glasses. i think.
He wears glasses to stop him from burning stuff with his eyes. They are red because you can see his eyes through them.
That depends if you are fixing a part of them, or not. I don't see it as the best adhesive for fixing any part of eyeglasses, but then you may have different glasses than I do.