Our eyes need light in order to see. While we do not understand every aspect of light, we do know how it travels. A ray of light can be reflected, deflected, absorbed, or bent. When light travels through a lens or water, its path is refracted or bent. When the light that enters the eye does not focus directly on the retina, it causes a refractive error.
What Are Refractive Errors?
Refractive errors are a type of vision problem that makes it difficult for a person to see clearly. Checking for refractive errors is the primary part of the standard eye exam. They can be treated with the help of prescription eyeglasses, contact lenses, or surgery. There are four main types of refractive errors:
- Myopia (nearsightedness)
- Hyperopia (farsightedness)
- Presbyopia (inability of the lens to focus)
- Astigmatism (a refractive issue based on the shape of the eyes’ cornea)
How Do The Eyes See?
The eye contains certain structures that contain refractive properties similar to lenses or water, and can bend light rays into a specific point of focus. This is essential for sharp vision.
Most eye refraction occurs when rays of light travel through the curved, clear front surface of the eye (cornea). The eye's lens then further bends light rays..
The process of vision begins when rays of light reflect off objects and pass through the eye’s optical system. The rays of light are then refracted and focused into a point of sharp focus. For clear vision, the focus point should be on the retina, the back part of the eye. The retina has nerves to capture the light rays The retinal nerves transmit signals through the optic nerve from the eye to the brain, where they are interpreted.
What Is Eye Refraction?
Eye refraction is how the power for a person’s eyeglasses or contact lenses is calculated. This measurement is based on the curve of the cornea, the lens, and the length of the eye. The optical prescription is determined by the refraction test, also known as a vision test, which is part of your standard eye examination. This refraction allows your eye doctor to provide the eyeglass or contact lens prescription to achieve clear vision.
Eyes change as we age and regular testing helps your eye doctor learn if you need a new prescription. Schedule a refraction test at EYEcenter Optometric in , Gold River, Rocklin, Folsom, Sacramento.
At EYEcenter Optometric, we put your family's needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 916-727-6518 or book an appointment online to see one of our Citrus Heights eye doctors.
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