Glasses normally used for vision correction or eye protection.

Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or radiation. Sunglasses allow better vision in bright daylight, and may protect against damage from high levels of ultraviolet light. Other types of glasses may be used for viewing visual information (such as stereoscopy) or simply just for aesthetic or fashion purposes.

Glasses are typically supported by pads on the bridge of the nose and by temple arms (sides) placed over the ears. CR-39 lenses are the most common plastic lenses due to their low weight, high scratch resistance, low dispersion, and low transparency to ultraviolet and infrared radiation. Polycarbonate and Trivex lenses are the lightest and most shatter-resistant, making them the best for impact protection.

Though frames can be both lightweight and flexible, and new lens materials and optical coatings are resistant to breakage and scratching, glasses can pose problems during rigorous sports. Scraping, fracturing, or breakage of the lenses can require repair by an optician.

Westside Eye Clinic also offers contact lenses as an alternative to glasses.

Eyeglasses normally correct and compensate for four types of vision deficiencies:

Myopia

A vision disorder that causes far objects to appear blurred but near objects to be seen clearly. Individuals suffering from myopia are prescribed eyeglasses with concave lenses, which compensate for the refraction error by moving the image of the distant objects that cannot be seen clearly backward onto the retina.

Correcting Hypermetropia

This is normally done with eyeglasses with convex lenses. With this disorder, the patients can see distant objects clearly but they have trouble with seeing objects that are close to them. Eyeglasses with convex lenses compensate for the refraction errors by moving the image of a nearby object that cannot be seen clearly forward onto the retina.

Astigmatism

Typically corrected with a cylindrical lens. This disorder is caused by a non-uniform curvature in the refractive surfaces of the eye, which leads to an abnormality in focusing the light rays on the retina. As a result, a part of the light rays are focused on the retina and the other part is focused behind it or in front of it.

Presbyopia

A condition where the eye exhibits a progressively diminished ability to focus on near objects with age. It is more frequent in people over 40 years old and it is corrected with convex lenses. These patients need reading or bifocal eyeglasses.

Type of Lens:

  • Bifocals

  • Trifocals

  • Progressive

  • Extreme magnification (bioptics)

Types of Glasses:

  • Corrective

  • Safety

  • Sunglasses

  • Ready-made reading glasses