Accommodation – The process by which the eye increases optical power to maintain a clear image (focus) on the retina.

Balanced View Optics™ Technology – AMO’s patented lens design that provides an optimal balance of near and distance vision for cataract patients. Distributes light over five optical zones for enhanced restoration of visual function, providing distance, intermediate and near vision for reduced spectacle dependence.

Cataract – A cloudiness or opacity that develops in the natural crystalline lens of the eye or in its envelope. Cataracts typically progress slowly to cause vision loss and can potentially cause blindness if untreated.

Crystalline lens – The eye's natural lens that helps bring rays of light to a focus on the retina. The original state of the lens is transparent, but it can become cloudy with age (cataract).

Cornea – The transparent front part of the eye that covers the iris, pupil and anterior chamber and provides most of the eye’s optical power. Together with the crystalline lens, the cornea refracts light and helps the eye to focus. The cornea contributes more to the total refraction than the lens does, but while the curvature of the lens can be adjusted to "tune" the focus, the curvature of the cornea is fixed.

Halo – Hazy ring around bright lights seen by some patients. This symptom may occur after surgery.

Hyperopia – Also known as farsightedness, hyperopia is a vision defect caused by an imperfection in the eye (often when the eyeball is too short or when the lens cannot become round enough), causing inability to focus on near objects and in extreme cases causing a sufferer to be unable to focus on objects at any distance.

Intraocular lens – Artificial intraocular lens that is implanted within the eye to replace the eye’s natural crystalline lens that has been removed due to cataract or other problem. The intraocular lens remains permanently in the eye.

Monofocal Lens – An implantable intraocular lens that provides good distance and sometimes intermediate vision but doesn’t correct near vision. Usually requires corrective lenses or eyeglasses after surgery for reading and near-vision tasks.

Multifocal Lens – An implantable intraocular lens that is designed to provide distance and near vision simultaneously. Some multifocal lenses also provide intermediate vision. Increased glare and halos at night have been reported with multifocal lenses.

Myopia – Also known as nearsightedness, myopia is an eyesight abnormality resulting from the eye's faulty refractive ability. People with myopia typically can see nearby objects clearly, but distant objects appear blurred.

Phacoemulsification – Use of ultrasonic vibration to break up a cataract, making it easier to remove.

Presbyopia – Farsightedness resulting from a reduced ability to focus. This is caused by a loss of elasticity of the crystalline lens that comes with age. This loss of flexibility limits the ability of the eye to change its point of focus from distance to near. Most people do not begin to experience the effects of presbyopia until their forties. Because of this normal process, people begin to wear bifocal glasses or other reading correction.

Pupil – The opening at the center of the iris of the eye that varies in diameter depending upon the brightness of the light coming into the eye.

Optic nerve – The optic nerve connects the eye to the brain. The optic nerve carries the impulses formed by the retina. These impulses are dispatched through the optic nerve to the brain, which interprets them as images.

Retina – The light-sensitive layer that lines the back of the eye, senses light and creates impulses. The retina sends light rays as electrical pulses via the optic nerve to the brain, enabling our mind to “see” what is in our field of vision.

Spherical aberration – An image imperfection that occurs due to the increased refraction of light rays that occurs when rays strike a lens or mirror near its edge rather than nearer the center.