Rx Eyewear - Eye Facts

Eye Technical Diagram

What is an Optician?

An optician is a technician who makes, verifies and delivers lenses, frames and other custom-fabricated optical devices upon prescription to the intended wearer. The optician's functions include prescription analysis and interpretation; determination of the lens forms best suited to the wearer's needs; the preparation and delivery of work orders for the grinding of lenses and the fabrication of eye wear; the verification of the finished ophthalmic products; and the adjustment, replacement, repair and reproduction of previously prepared ophthalmic lenses, frames and other specially-fabricated ophthalmic devices.

What is a Optometrist?

Optometrists are health service providers who are involved exclusively with vision problems. They are provincially licensed to examine the eyes and to determine the presence of vision problems. An optometrist is not a medical doctor, but is a doctor of optometry (O.D.). They cannot perform surgery, but they often provide patients with pre- and post-surgical care. Optometrists may perform all services listed under the definition of an optician.

What is an Ophthalmologist?

An ophthalmologist is a physician who specializes in the medical and surgical care of the eyes and visual system and in the prevention of eye disease and injury. An ophthalmologist is a specialist who is qualified by lengthy medical education, training and experience to diagnose, treat and manage all eye and visual systems and is licensed by a provincial board to practice medicine and surgery. An ophthalmologist can deliver total eye care, diagnose general diseases of the body and treat ocular manifestations of systemic diseases.

What is Macular Degeneration?

Macular Degeneration commonly affects people over 50 years of age and can cause blindness. It is often referred to as AMD - Age related Macular Degeneration. The light sensitive Macula at the back of the eye becomes damaged by AMD, causing changes in vision resulting in "blind spots" AMD usually starts in one eye, forcing the other eye to compensate. There is a hereditary link to AMD. Contact your eye care professional if you notice vision changes. Everyone over 40 should have regular eye examinations.

What is Glaucoma?

Glaucoma commonly affects people over the age of 40 and can cause blindness. Increased pressure within the eye is a risk factor for Glaucoma. Pressure on the optic nerve, at the back of the eye causes a loss of side (peripheral) vision. Contact your eye care professional if you have any visual disturbance that is not corrected by glasses.

What is Myopia (or nearsightedness)? - the inability to see clearly at a distance.

Nearsightedness is a result of the eye being slightly longer than usual from front to back. This can cause images to focus in front of the retina instead of directly on its surface. As a result, far objects appear blurred and are difficult to focus upon. Myopia is measured using negative diopters. The further the number of diopters is from zero, the more pronounced the myopia or nearsightedness. Nikon offers a variety of single vision lenses designed to correct this condition and allow for a return to normal vision.

What is Hyperopia (or farsightedness)? - the inability to see clearly up close.

This condition occurs when the eye is too short from front to back. As a result, images focus behind the retina instead of directly on its surface. When people are farsighted, close objects appear blurry and difficult to focus on. Hyperopia is measured in positive diopters. The farther the number of diopters is from zero, the more pronounced the farsightedness. Nikon has a variety of single vision lenses designed to eliminate the problems of hyperopia for a return to a more normal, natural vision.

What is Astigmatism? - rather than just being blurred, an image appears distorted, causing imprecise vision at any distance.

Astigmatism is a refractive error caused by an irregularly shaped cornea, appearing more oblong, like a football, as opposed to the more normal spherical form. Measured in diopters, cylinder meridian or axis, astigmatism can cause double images or ghosting. These visual distortions can be corrected with any of a variety of single vision lenses designed to help you see the world as it actually exists.

What is Presbyopia? - the inability to see close objects.

This form of eyesight deterioration - specifically near vision - comes naturally with age and is caused by the loss of flexibility in the eye's lens. As we age, elasticity in the lens is reduced. Presbyopia, the lack of flexibility of the crystalline lens of your eye, makes it difficult to focus on objects that are near.

You may have presbyopia if you show one or more of the following signs: tendency to hold reading material at arm's length, blurred vision when holding reading material at a normal length, or eye fatigue and headaches when reading closely. To compensate for the signs and symptoms of presbyopia, Nikon recommends either a near-intermediate lens or a progressive lens.